Search

Multiple intramuscular variables have been proposed to explain the high variability in resistance training induced muscle hypertrophy across humans. This study investigated if muscular androgen receptor (AR), estrogen receptor α (ERα) and β (ERβ) content and fiber capillarization are associated with fiber and whole‐muscle hypertrophy after chronic resistance training. Male (n = 11) and female (n = 10) resistance training novices (22.1 ± 2.2 years) trained their knee extensors 3×/week for 10 weeks. Vastus lateralis biopsies were taken at baseline and post the training period to determine changes in fiber type specific cross‐sectional area (CSA) and fiber capillarization by immunohistochemistry and, intramuscular AR, ERα and ERβ content by Western blotting. Vastus lateralis volume was quantified by MRI‐based 3D segmentation. Vastus lateralis muscle volume significantly increased over the training period (+7.22%; range: −1.82 to +18.8%, p < 0.0001) but no changes occurred in all fiber (+1.64%; range: −21 to +34%, p = 0.869), type I fiber (+1.33%; range: −24 to +41%, p = 0.952) and type II fiber CSA (+2.19%; range: −23 to +29%, p = 0.838). However, wide inter‐individual ranges were found. Resistance training increased the protein expression of ERα but not ERβ and AR, and the increase in ERα content was positively related to changes in fiber CSA. Only for the type II fibers, the baseline capillary‐to‐fiber‐perimeter index was positively related to type II fiber hypertrophy but not to whole muscle responsiveness. In conclusion, an upregulation of ERα content and an adequate initial fiber capillarization may be contributing factors implicated in muscle fiber hypertrophy responsiveness after chronic resistance training. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to determine whether a 9‐week resistance training program based on high load (HL) versus low load combined with blood flow restriction (LL‐BFR) induced a similar (i) distribution of muscle hypertrophy among hamstring heads (semimembranosus, SM; semitendinosus, ST; and biceps femoris long head, BF) and (ii) magnitude of tendon hypertrophy of ST, using a parallel randomized controlled trial. Methods: A total of 45 participants were randomly allocated to one of three groups: HL, LL‐BFR, and control (CON). Both HL and LL‐BFR performed a 9‐week resistance training program composed of seated leg curl and stiff‐leg deadlift exercises. Freehand 3D ultrasound was used to assess the changes in muscle and tendon volume. Results: The increase in ST volume was greater in HL (26.5 ± 25.5%) compared to CON (p = 0.004). No difference was found between CON and LL‐BFR for the ST muscle volume (p = 0.627). The change in SM muscle volume was greater for LL‐BFR (21.6 ± 27.8%) compared to CON (p = 0.025). No difference was found between HL and CON for the SM muscle volume (p = 0.178).There was no change in BF muscle volume in LL‐BFR (14.0 ± 16.5%; p = 0.436) compared to CON group. No difference was found between HL and CON for the BF muscle volume (p = 1.0). Regarding ST tendon volume, we did not report an effect of training regimens (p = 0.411). Conclusion: These results provide evidence that the HL program induced a selective hypertrophy of the ST while LL‐BFR induced hypertrophy of SM. The magnitude of the selective hypertrophy observed within each group varied greatly between individuals. This finding suggests that it is very difficult to early determine the location of the hypertrophy among a muscle group. [ABSTRACT FROM AUTHOR]

Introduction: High exercise adherence is a key factor for effective exercise programmes. However, little is known about predictors of exercise adherence to a multimodal machine‐based training in older retirement home residents. Aims: To assess exercise adherence and potential predictors of adherence. Furthermore, to evaluate user acceptance of the multimodal training and the change in exercise self‐efficacy. Methods: In this sub‐analysis of the bestform‐F study, a total of 77 retirement home residents ≥65 years (mean age: 85.6 ± 6.6 years, 77.9% female) participated in a 6‐month machine‐based resistance, coordination and endurance training. Attendance to the training was documented for each training session. To identify potential predictors a multiple linear regression model was fitted to the data. Analyzed predictors included age, sex, body mass index (BMI), physical function, exercise self‐efficacy, and physical activity history. Different domains of user acceptance (e.g. safety aspects, infrastructure) and exercise self‐efficacy were assessed by a questionnaire and the exercise self‐efficacy scale (ESES), respectively. Results: Mean exercise adherence was 67.2% (median: 74.4%). The regression model (R2 = 0.225, p = 0.033) revealed that the 6‐minute walk test (6‐MWT) at baseline significantly predicted exercise adherence (β: 0.074, 95% confidence interval (CI): 0.006–0.142, p = 0.033). Different user domains were rated at least as good by 83.9%–96.9% of participants, reflecting high acceptance. No statistically significant change was found for exercise self‐efficacy over 6 months (mean change: 0.47 ± 3.08 points, p = 0.156). Conclusion: Retirement home residents attended more than two thirds of offered training sessions and physical function at baseline was the key factor for predicting adherence. User acceptance of the training devices was highly rated. These findings indicate good potential for implementation of the exercise programme. [ABSTRACT FROM AUTHOR]

Introduction: The number of randomized controlled trials (RCTs) investigating the effects of exercise among cancer survivors has increased in recent years; however, participants dropping out of the trials are rarely described. The objective of the present study was to assess which combinations of participant and exercise program characteristics were associated with dropout from the exercise arms of RCTs among cancer survivors. Methods: This study used data collected in the Predicting OptimaL cAncer RehabIlitation and Supportive care (POLARIS) study, an international database of RCTs investigating the effects of exercise among cancer survivors. Thirty‐four exercise trials, with a total of 2467 patients without metastatic disease randomized to an exercise arm were included. Harmonized studies included a pre and a posttest, and participants were classified as dropouts when missing all assessments at the post‐intervention test. Subgroups were identified with a conditional inference tree. Results: Overall, 9.6% of the participants dropped out. Five subgroups were identified in the conditional inference tree based on four significant associations with dropout. Most dropout was observed for participants with BMI >28.4 kg/m2, performing supervised resistance or unsupervised mixed exercise (19.8% dropout) or had low‐medium education and performed aerobic or supervised mixed exercise (13.5%). The lowest dropout was found for participants with BMI >28.4 kg/m2 and high education performing aerobic or supervised mixed exercise (5.1%), and participants with BMI ≤28.4 kg/m2 exercising during (5.2%) or post (9.5%) treatment. Conclusions: There are several systematic differences between cancer survivors completing and dropping out from exercise trials, possibly affecting the external validity of exercise effects. [ABSTRACT FROM AUTHOR]

Introduction: Among the limited studies on physical exercise interventions in adults with cystic fibrosis (CF), few have specifically addressed the improvement of peripheral muscle strength and body fat‐free mass. The aim of this study was to examine the impacts of a remotely supervised, individualized 8‐week resistance training program of moderate to high intensity on strength and body composition in these subjects. Methods: This was a randomized controlled trial performed in adults with CF. The exercise group (EX) performed three 1‐h resistance training sessions per week over 8 weeks. The control group (CON) followed the physical activity recommendations of their physician. The main outcomes were muscle strength and body composition, with secondary measures including pulmonary function and quality of life. Two‐way repeated measures analysis was used. Results: In 23 participants (age 32.13 ± 7.72 years), the intervention showed a significant beneficial effect on leg press strength, with a large effect size, both in absolute (p = 0.011; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.281) and relative (p = 0.007; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.310) terms. Large intervention effects were observed on total fat mass (p < 0.001; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.415), body adiposity index (p < 0.001; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.436), and fat mass index (p < 0.001; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.445), all showing reduction in the EX group. In addition, significant large size effects were detected on total fat‐free mass (p = 0.046; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.177), trunk fat‐free mass (p = 0.039; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.188), and fat‐free mass index (p = 0.048; ηp2$$ {\eta}_{\mathrm{p}}^2 $$ = 0.174), all favoring exercise. No significant effects were observed on pulmonary function and quality of life. Conclusions: An 8‐week remotely supervised resistance training program, with moderate to high intensity, effectively improved lower limb muscle strength and body composition. [ABSTRACT FROM AUTHOR]

Objectives: This systematic review evaluated the safety and efficacy of blood flow restriction exercise (BFRE) on skeletal muscle size, strength, and functional performance in individuals with neurological disorders (ND). Methods: A literature search was performed in PubMed, CINAHL, and Embase. Two researchers independently assessed eligibility and performed data extraction and quality assessments. Eligibility criteria: Study populations with ND, BFRE as intervention modality, outcome measures related to safety or efficacy. Results: Out of 443 studies identified, 16 were deemed eligible for review. Three studies examined the efficacy and safety of BFRE, one study focused on efficacy results, and 12 studies investigated safety. Disease populations included spinal cord injury (SCI), inclusion body myositis (sIBM), multiple sclerosis (MS), Parkinson's disease (PD), and stroke. A moderate‐to‐high risk of bias was presented in the quality assessment. Five studies reported safety concerns, including acutely elevated pain and rating of perceived exertion levels, severe fatigue, muscle soreness, and cases of autonomic dysreflexia. Two RCTs reported a significant between‐group difference in physical function outcomes, and two RCTs reported neuromuscular adaptations. Conclusion: BFRE seems to be a potentially safe and effective training modality in individuals with ND. However, the results should be interpreted cautiously due to limited quality and number of studies, small sample sizes, and a general lack of heterogeneity within and between the examined patient cohorts. [ABSTRACT FROM AUTHOR]

Introduction: Male elite cyclists (average VO2‐max: 71 mL/min/kg, n = 18) completed 7 weeks of high‐intensity interval training (HIT) (3×/week; 4‐min and 30‐s intervals) during the competitive part of the season. The influence of a maintained or lowered total training volume combined with HIT was evaluated in a two‐group design. Weekly moderate‐intensity training was lowered by ~33% (~5 h) (LOW, n = 8) or maintained at normal volume (NOR, n = 10). Endurance performance and fatigue resistance were evaluated via 400 kcal time‐trials (~20 min) commenced either with or without prior completion of a 120‐min preload (including repeated 20‐s sprints to simulate physiologic demands during road races). Results: Time‐trial performance without preload was improved after the intervention (p = 0.006) with a 3% increase in LOW (p = 0.04) and a 2% increase in NOR (p = 0.07). Preloaded time‐trial was not significantly improved (p = 0.19). In the preload, average power during repeated sprinting increased by 6% in LOW (p < 0.01) and fatigue resistance in sprinting (start vs end of preload) was improved (p < 0.05) in both groups. Blood lactate during the preload was lowered (p < 0.001) solely in NOR. Measures of oxidative enzyme activity remained unchanged, whereas the glycolytic enzyme PFK increased by 22% for LOW (p = 0.02). Conclusion: The present study demonstrates that elite cyclists can benefit from intensified training during the competitive season both with maintained and lowered training volume at moderate intensity. In addition to benchmarking the effects of such training in ecological elite settings, the results also indicate how some performance and physiological parameters may interact with training volume. [ABSTRACT FROM AUTHOR]

Substantial research has supported using musical stimuli as an ergogenic aid before and during various forms of exercise. Researchers have demonstrated that music shifts attention from associative to dissociative, decreases perceived effort and discomfort, and increases arousal and pleasantness in longer‐duration, low‐to‐moderate‐intensity exercises. Strength training is shorter in duration and higher in intensity than aerobic or muscular endurance training. Limited research has examined the effects of music on strength performance and psychological outcomes. Therefore, the purpose of this study was to investigate the effects of the tempo of self‐selected music on isokinetic knee extension and flexion performance, effort, discomfort, attention, arousal, and pleasantness in resistance‐trained young adults. Thirty resistance‐trained college‐aged adults completed three exercise testing sessions. In a randomized, counterbalanced order, a repeated measures design was used to expose the participants to three conditions (fast music, slow music, and no music). The Biodex isokinetic dynamometer and standardized psychological Likert‐style scales were used to measure concentric maximum effort knee extension and flexion torque at 60°/s and psychological variables, respectively. This study found that music improves knee extension torque but not knee flexion in resistance‐trained young adults. In addition, music or the tempo of music did not influence any psychological outcomes during isokinetic strength testing. Therefore, listening to music is not detrimental to performance or psychological outcomes, but this study provides minimal support for music's use as an ergogenic aid during strengthening exercise. [ABSTRACT FROM AUTHOR]

Studies examining the effect of protein (PRO) feeding on post resistance exercise (RE) muscle protein synthesis (MPS) have primarily been performed in men, and little evidence is available regarding the quantity of PRO required to maximally stimulate MPS in trained women following repeated bouts of RE. We therefore quantified acute (4 h and 8 h) and extended (24 h) effects of two bouts of resistance exercise, alongside protein‐feeding, in women, and the PRO requirement to maximize MPS. Twenty‐four RE trained women (26.6 ± 0.7 years, mean ± SEM) performed two bouts of whole‐body RE (3 × 8 repetitions/maneuver at 75% 1‐repetition maximum) 4 h apart, with post‐exercise ingestion of 15 g, 30 g, or 60 g whey PRO (n = 8/group). Saliva, venous blood, and a vastus lateralis muscle biopsy were taken at 0 h, 4 h, 8 h, and 24 h post‐exercise. Plasma leucine and branched chain amino acids were quantified using gas chromatography mass spectrometry (GC–MS) after ingestion of D2O. Fifteen grams PRO did not alter plasma leucine concentration or myofibrillar synthetic rate (MyoFSR). Thirty and sixty grams PRO increased plasma leucine concentration above baseline (105.5 ± 5.3 μM; 120.2 ± 7.4 μM, respectively) at 4 h (151.5 ± 8.2 μM, p < 0.01; 224.8 ± 16.0 μM, p < 0.001, respectively) and 8 h (176.0 ± 7.3 μM, p < 0.001; 281.7 ± 21.6 μM, p < 0.001, respectively). Ingestion of 30 g PRO increased MyoFSR above baseline (0.068 ± 0.005%/h) from 0 to 4 h (0.140 ± 0.021%/h, p < 0.05), 0 to 8 h (0.121 ± 0.012%/h, p < 0.001), and 0 to 24 h (0.099 ± 0.011%/h, p < 0.01). Ingestion of 60 g PRO increased MyoFSR above baseline (0.063 ± 0.003%/h) from 0 to 4 h (0.109 ± 0.011%/h, p < 0.01), 0 to 8 h (0.093 ± 0.008%/h, p < 0.01), and 0 to 24 h (0.086 ± 0.006%/h, p < 0.01). Post‐exercise ingestion of 30 g or 60 g PRO, but not 15 g, acutely increased MyoFSR following two consecutive bouts of RE and extended the anabolic window over 24 h. There was no difference between the 30 g and 60 g responses. [ABSTRACT FROM AUTHOR]

The present study compared the ipsilateral repeated bout effect (IL‐RBE) and contralateral repeated bout effect (CL‐RBE) of the elbow flexors (EF) and knee flexors (KF) for the same interval between bouts to shed light on their mechanisms. Fifty‐two healthy sedentary young (20–28 years) men were randomly assigned to the IL‐EF, IL‐KF, CL‐EF, and CL‐KF groups (n = 13/group). Thirty maximal eccentric contractions of the EF were performed in IL‐EF and CL‐EF, and 60 maximal eccentric contractions of the KF were performed in IL‐KF and CL‐KF, with a 2‐week interval between bouts. Changes in muscle damage markers such as maximal voluntary contraction (MVC) torque, muscle soreness, and plasma creatine kinase activity, and proprioception measures before to 5 days post‐exercise were compared between groups. Changes in all variables were greater (p < 0.05) after the first than second bout for all groups, and the changes were greater (p < 0.05) for the EF than KF. The changes in all variables after the second bout were greater (p < 0.05) for the CL than IL condition for both EF and KF. The magnitude of the average protective effect was similar between CL‐EF (33%) and CL‐KF (32%), but slightly greater (p < 0.05) for IL‐EF (67%) than IL‐KF (61%). These demonstrate that the magnitude of CL‐RBE relative to IL‐RBE was similar between the EF and KF (approximately 50%), regardless of the greater muscle damage for the EF than KF. It appears that the CL‐RBE is more associated with neural adaptations at cerebrum, cerebellum, interhemispheric inhibition, and coricospinal tract, but the IL‐RBE is induced by additional adaptations at muscles. [ABSTRACT FROM AUTHOR]

The aim of the present investigation was twofold. (1) to assess test–retest reliability of normalized mutual information (NMI) values extracted from the surface electromyography (sEMG) signal of muscles pairs of the upper body during dynamic bench press at a high load, and (2) to assess changes in NMI values from before to after a five‐week quasi‐randomized controlled bench press training intervention. For test–retest reliability, 20 strength trained males (age 25 ± 2 years, height 1.81 ± 0.07 m) performed two three‐repetition maximum (3RM) tests in bench press, while sEMG was recorded from six upper body muscles. Tests were separated by 8.2 ± 2.9 days. For the training intervention, 17 male participants (age 26 ± 5 years, height 1.80 ± 0.07 m) trained bench press specific strength training for 5 weeks (TRA), while 13 male participants (age 23 ± 3 years, height 1.80 ± 0.08 m) constituted a control group (CON). 3RM bench press test and sEMG recordings were carried out before and after the intervention period. The NMI values ranged from poor to almost perfect reliability, with the majority displaying substantial reliability. TRA displayed a significant decrease in NMI values during the concentric phase for two agonist–agonist muscle pairs, while one agonist–agonist and two agonist–antagonist muscle pairs increased the NMI values during the eccentric phase. The observed changes did not exceed the minimal detectable threshold, and we therefore cannot surely ascertain that the changes observed in NMI values reflect genuine neural adaptations. [ABSTRACT FROM AUTHOR]

It is vital from the public health and educational perspective to be familiar with changes in the fitness levels of individuals and populations since fitness is associated with several health outcomes and cognition. Skill‐related physical fitness refers to performance in sports or occupation and is associated with motor skill performance. The aim of the present study was to examine secular trends in skill‐related physical fitness of 16 678 participants in four youth generations of Slovenian children and adolescents in years 1983 (n = 3128), 1993/94 (n = 3413), 2003/04 (n = 5497), and 2013/14 (n = 4640). Using repeated cross‐sectional design, we observed fitness level of all participants divided into three age groups: 6–10, 11–14, and 15–19 years. Skill‐related physical performance was measured with seven fitness tests for speed, coordination, balance, and flexibility. Analysis of covariance was used to compare differences in fitness performance between decades in each age and sex group, adjusted for body height, body weight, and body mass index. Overall, large but inconsistent changes in coordination, a small improvement in speed, and a decline in flexibility were seen. The trends over the whole examined period were not linear throughout decades. Generally, positive trends were noticed in periods 1983–1993 (range 1.4%–17.9%; except flexibility) and 2003/04–2013/14 (range 0.2%–36.4%; except age group 15–19 years) while in the period 1993/94–2003/04 there are some particularities in secular trends according to individual components as well as age groups. In general, the secular trend showed a positive direction for both genders (p < 0.05), except for gross motor coordination, which demonstrated positive trends in 1993 and 2013 compared with a decade earlier (p < 0.05) and from 1983 to 2013/14, except for the youngest boys in 2003 and the youngest girls from 1993 to 2003 (p < 0.05). Our findings call for exercise programs aimed at improving speed and gross motor coordination in both sexes and all age groups, especially in the group of 15–19 years old. [ABSTRACT FROM AUTHOR]

Background: Although the superior effectiveness of free‐weight over machine‐based training has been a traditionally widespread assumption, longitudinal studies comparing these training modalities were scarce and heterogeneous. Objective: This research used the velocity‐based method to compare the effects of free‐weight and machine‐based resistance training on athletic performance and muscle architecture. Methods: Thirty‐four resistance‐trained men participated in an 8‐week resistance training program allocated into free‐weight (n = 17) or machine‐based (n = 17) groups. Training variables (intensity, intraset fatigue, and recovery) were identical for both groups, so they only differed in the use of a barbell or specific machines to execute the full squat, bench press, prone bench pull, and shoulder press exercises. The velocity‐based method was implemented to accurately adjust the planned intensity. Analysis of covariance and effect size (ES) statistics were used to compare both training modalities on a comprehensive set of athletic and muscle architecture parameters. Results: No between‐group differences were found for any athletic (p ≥ 0.146) and muscle architecture (p ≥ 0.184) variable. Both training modalities significantly and similarly improved vertical jump (Free‐weight: ES ≥ 0.45, p ≤ 0.001; Machine‐based: ES ≥ 0.41, p ≤ 0.001) and lower limb anaerobic capacity (Free‐weight: ES ≥ 0.39, p ≤ 0.007; Machine‐based: ES ≥ 0.31, p ≤ 0.003). Additionally, the machine‐based group meaningfully enhanced upper limb anaerobic power (ES = 0.41, p = 0.021), whereas the free‐weight group significantly improved the change of direction (ES = ‐0.54, p = 0.003) and 2/6 balance conditions analyzed (p ≤ 0.012). Changes in sprint capacity (ES ≥ ‐0.13, p ≥ 0.274), fascicle length, and pennation angle (ES ≤ 0.19, p ≥ 0.129) were not significant for either training modality. Conclusion: Adaptations in athletic performance and muscle architecture would not be meaningfully influenced by the resistance modality trained. [ABSTRACT FROM AUTHOR]

Aging involves a marked decline in physical function and especially muscle power. Thus, optimal resistance exercise (RE) to improve muscle power is required for exercise prescription. An eccentric lowering phase immediately before a concentric lift (ECC‐CON) may augment concentric power production, due to various proposed mechanisms (e.g., elastic recoil, pre‐activation, stretch reflex, contractile history), when compared with a concentric contraction alone (CON‐Only). This study compared the effect of a prior eccentric lowering phase on older adult concentric power performance (ECC‐CON vs. CON‐Only) during a common multiple joint isoinertial RE (i.e., leg press) with a range of loads. Twelve healthy older adult males completed two measurement sessions, consisting of ECC‐CON and CON‐Only contractions, performed in a counterbalanced order using 20–80% of one repetition maximum [% 1RM] loads on an instrumented isoinertial leg press dynamometer that measured power, force, and velocity. Muscle activation was assessed with surface electromyography (sEMG). For mean power ECC‐CON>CON‐Only, with a pronounced effect of load on the augmentation of power by ECC‐CON (+19 to +55%, 35–80% 1RM, all p < 0.032). Similarly, for mean velocity ECC‐CON>CON‐Only, especially as load increased (+15 to 54%, 20–80% 1RM, all p < 0.005), but mean force showed more modest benefits of ECC‐CON (+9 to 14%, 50–80% 1RM, all p < 0.05). In contrast, peak power and velocity were similar for ECC‐CON and CON‐Only with all loads. Knee and hip extensor sEMG were similar for both types of contractions. In conclusion, ECC‐CON contractions produced greater power, and velocity performance in older adults than CON‐Only and may provide a superior stimulus for chronic power development. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to assess the residual effects of a 12‐week concurrent training program (power training + high‐intensity interval training) in older adults with chronic obstructive pulmonary disease (COPD). Methods: A total of 21 older adults with COPD [intervention (INT), n = 8; control (CON), n = 13; 76.9 ± 6.8 years] were assessed at baseline and 10 months after the completion of the intervention by the short physical performance battery (SPPB), health‐related quality of life (EQ‐5D‐5L), vastus lateralis muscle thickness (MT), peak pulmonary oxygen uptake (peak VO2) and peak work rate (Wpeak), early and late isometric rate of force development (RFD), leg and chest press maximum muscle power (LPmax and CPmax), and systemic oxidative damage and antioxidant capacity. Results: Compared to baseline, after 10 months of detraining, the INT group presented increased SPPB (∆ = 1.0 point), health‐related quality of life (∆ = 0.07 points), early RFD (∆ = 834 N∙s−1), LPmax (∆ = 62.2 W), and CPmax (∆ = 16.0 W) (all p < 0.05). In addition, a positive effect was noted in INT compared to CON regarding MT and Wpeak (both p < 0.05). No between‐group differences were reported in peak VO2, late RFD, systemic oxidative damage, and antioxidant capacity from baseline to 10 months after the completion of the intervention (all p > 0.05). Conclusions: Twelve weeks of concurrent training were enough to ensure improved physical function, health‐related quality of life, early RFD and maximum muscle power and to preserve MT and Wpeak but not peak VO2, late RFD, systemic oxidative damage and antioxidant capacity in the subsequent 10 months of detraining in older adults with COPD. [ABSTRACT FROM AUTHOR]

Circulating bile acids (BA) are signaling molecules that control glucose and lipid metabolism. However, the effects of acute exercise on plasma levels of BA in humans remain poorly understood. Here, we evaluate the effects of a bout of maximal endurance exercise (EE) and resistance exercise (RE) on plasma levels of BA in young, sedentary adults. Concentration of eight plasma BA was measured by liquid chromatography–tandem mass spectrometry before and 3, 30, 60, and 120 min after each exercise bout. Cardiorespiratory fitness (CRF) was assessed in 14 young adults (21.8 ± 2.5 yo, 12 women); muscle strength was assessed in 17 young adults (22.4 ± 2.5 yo, 11 women). EE transiently decreased plasma levels of total, primary, and secondary BA at 3 and 30 min after exercise. RE exerted a prolonged reduction in plasma levels of secondary BA (p < 0.001) that lasted until 120 min. Primary BA levels of cholic acid (CA) and chenodeoxycholic acid (CDCA) were different across individuals with low/high CRF levels after EE (p ≤ 0.044); CA levels were different across individuals with low/high handgrip strength levels. High CRF individuals presented higher levels of CA and CDCA 120 min after exercise vs baseline (+77% and +65%) vs the low CRF group (−5% and −39%). High handgrip strength levels individuals presented higher levels of CA 120 min after exercise versus baseline (+63%) versus the low handgrip strength group (+6%). The study findings indicate that an individual's level of physical fitness can influence how circulating BA respond to both endurance and resistance exercise. Additionally, the study suggests that changes in plasma BA levels after exercising could be related to the control of glucose homeostasis in humans. [ABSTRACT FROM AUTHOR]

The aim of the present cross‐sectional study was to determine if chronic rock climbing and climbing‐specific resistance training (RT) would modify the reticulospinal tract (RST) efficacy. Sixteen healthy, elite level climbers (CL; n = 16, 5 F; 29.8 ± 6.7 years) with 12 ± 7 years of climbing and climbing‐specific RT experience and 15 healthy recreationally active participants (CON; n = 15, 4 F; 24.6 ± 5.9 years), volunteered for the study. We quantified RST efficacy by comparing the effects of a startle stimulus over reaction time (Rtime) and measured rate of force development (RFD) and surface electromyography (sEMG) in representative muscles during powerful hand grip contractions. Both groups performed two Rtime tasks while performing rapid, powerful gripping with the right hand (Task 1) or during 3‐s‐long maximal voluntary right hand grip contractions in response to an imperative visual signal alone (V), or combined with a auditory‐non startle stimulus (A) or/and startling auditory stimulus (S). We also tested the reproducibility of these responses on two separate days in CON. Intersession reliability ranged from 0.34 to 0.96 for all variables. The CL versus CON was 37% stronger (p = 0.003). The S stimulus decreased Rtime and increased RFD and sEMG in both groups during both tasks (all p < 0.001). Rtime was similar between groups in all conditions. However, CL had a greater RFD from 50 to 100 ms compared with CON only after the S stimulus in both tasks (p < 0.05, d = 0.85–0.96). The data tentatively suggest that chronic rock climbing and climbing‐specific RT might improve RST efficacy, by increasing RST input to the α‐motoneurons. [ABSTRACT FROM AUTHOR]

Objective: The aim of the present study was to explore the influence of a concurrent exercise (aerobic + resistance) training program, from the 17th gestational week (g.w.) until birth on low back and sciatic pain, and pain disability. A total of 93 pregnant women divided into exercise (n = 49) and control (n = 44) groups followed a 60‐min, 3 days/week, concurrent exercise training. Methods: Low back and sciatic pain were measured with a Visual Analogic Scale (VAS). The disability resulting from pain was assessed with the Oswestry Disability Index (ODI). Measures were performed at the 16th and 34th g.w. Results: The exercise group increased 21.9 mm less the VAS low back (between‐group differences (B): 95% CI: −33.6 to −10.2; p < 0.001) and 12.9 mm less the VAS sciatica score (between‐group differences: 95% CI (B): −21.8 to −4.0; p = 0.005) than the control group. Regarding the ODI questionnaire, the exercise group increased 0.7, 0.5, and 0.7 less than the control group in pain while sleeping (between‐group differences (B): 95% CI: −1.4 to −0.01; p = 0.025), pain while lifting weight (between‐group differences (B): 95% CI: −0.9 to −0.01; p = 0.016), and limitations of the social life due to pain (between‐group differences(B): 95% CI: −1.3 to −0.06; p = 0.032). Furthermore, the exercise group suffered 6.9% less pain than the control group in the ODI total score (between‐group differences (B): 95% CI: −13.9 to 0.053; p = 0.052). Conclusion: This concurrent exercise training program adapted to pregnant women improved pain compared to controls. [ABSTRACT FROM AUTHOR]

Purpose: Recent evidence indicates that low‐load blood flow restriction (LL‐BFR) training elicits an anabolic response in tendinous tissue. The purpose of the present study was to investigate the hypertrophic pattern induced in the Achilles tendon by LL‐BFR, in comparison with the regional hypertrophy typically observed with conventional high‐load (HL) resistance training. Methods: N = 40 male participants were randomly and concealed allocated to one of two groups: LL‐BFR training (20–35% one‐repetition maximum/1RM) or HL training (70–85% 1RM). The training was completed three times per week for a total of 14 weeks. Before and after the training period, Achilles tendon morphology was assessed using magnetic resonance imaging along the entire tendon length. Additionally, dynamic strength measures of the plantar flexors were evaluated. Results: In line with previous findings, dynamic plantar flexion strength was improved to a comparable extent in both groups (LL‐BFR: 43.6%; HL: 43.5%). The results also confirmed significant increases in Achilles tendon cross‐sectional area with LL‐BFR (+5.2%). Moreover, they revealed that the hypertrophic pattern obtained with LL‐BFR was similar to regional changes seen with conventional HL training. Conclusion: The present findings point towards the notion that despite the low loads being applied, LL‐BFR training induces Achilles tendon hypertrophy by potentiating anabolic responses in the same regions as with conventional high‐load training. Future studies are needed to (i) focus on the potential mechanisms underlying these tendon morphology changes and (ii) apply and evaluate LL‐BFR training in clinical populations to validate these results in rehabilitative settings. [ABSTRACT FROM AUTHOR]

This study investigated the effects of a relatively high‐ versus moderate‐volume resistance training program on changes in lean mass during caloric restriction. Thirty‐eight resistance‐trained males were randomized to perform either a high‐volume (HVG; 5 sets/exercise) or a moderate‐volume (MVG; 3 sets/exercise) resistance training program. Both groups were supervised during lower body training. Participants consumed 30 kcal/kg for 6 weeks after 1 week of weight maintenance (45 kcal/kg), with protein intake fixed at 2.8 g/kg fat‐free mass. Muscle thickness of the m. rectus femoris, body composition, contractile properties, stiffness, mood, and sleep status were assessed at pre‐, mid‐, and post‐study. No significant group × time interaction was observed for muscle thickness of the m. rectus femoris at 50% (∆ [post‐pre] 0.36 ± 0.93 mm vs. ∆ −0.01 ± 1.59 mm; p = 0.226) and 75% length (∆ −0.32 ± 1.12 mm vs. ∆ 0.08 ± 1.14 mm; p = 0.151), contractility, sleep, and mood in the HVG and MVG, respectively. Body mass (HVG: ∆ −1.69 ± 1.12 kg vs. MVG: ∆ −1.76 ± 1.76 kg) and lean mass (∆ −0.51 ± 2.30 kg vs. ∆ −0.92 ± 1.59 kg) decreased significantly in both groups (p = 0.022), with no between‐group difference detected (p = 0.966). High‐volume resistance training appears to have neither an advantage nor disadvantage over moderate‐volume resistance training in terms of maintaining lean mass or muscle thickness. Given that both groups increased volume load and maintained muscle contractility, sleep quality, and mood, either moderate or higher training volumes conceivably can be employed by resistance‐trained individuals to preserve muscle during periods of moderate caloric restriction. [ABSTRACT FROM AUTHOR]

Grounded in hedonic assumptions, evidence suggests that people tend to engage in activities they consider pleasurable and enjoyable, while trying to avoid pain and displeasure. This suggests that the dynamic between positive and negative affect can influence current behavior and the intentions to continue performing. Regarding resistance training (RT), research focusing on how to promote a better affective response is still scarce and much needed. Given existing limitations and theoretical suggestions, a RT program was developed and applied to recreational exercisers in a quasi‐experimental design aiming to (1) explore the affective response dynamic through an assessment after the last set of each exercise; and (2) analyze possible differences of preference and tolerance profiles in affective variables (core affect and enjoyment). For that purpose, 43 participants (21 male and 22 female; Mage = 34.69 ± 6.71 years; Mexperience = 8.32 ± 4.54 years; MBMI = 24.26 ± 2.64 kg/m2) accepted to participate in this study. Descriptive statistics, correlational, and group comparisons analyses were performed to provide evidence for proposed objectives. The present study showed that measures of affective valence/arousal applied immediately after a set represents a feasible and ecologically valid approach to tap core affect. Results presented evidence that recreationally trained exercisers in a common RT program would need a minimum of one measurement to assess the affective response. However, additional assessments could refine the understanding of exercise pleasurable experience. Results also suggest that exercisers with distinct profiles of preference/tolerance depicted differentiated patterns for the affective response, possibly justifying a distinct approach when promoting affective regulation. [ABSTRACT FROM AUTHOR]

Combined heavy‐ and light‐load ballistic training is often employed in high‐performance sport to improve athletic performance and is accompanied by adaptations in muscle architecture. However, little is known about how training affects muscle‐tendon unit (MTU) kinematics during the execution of a sport‐specific skill (e.g., jumping), which could improve our understanding of how training improves athletic performance. The aim of this study was to investigate vastus lateralis (VL) MTU kinematics during a countermovement jump (CMJ) following combined ballistic training. Eighteen young, healthy males completed a 10‐week program consisting of weightlifting derivatives, plyometrics, and ballistic tasks under a range of loads. Ultrasonography of VL and force plate measurements during a CMJ were taken at baseline, mid‐test, and post‐test. The training program improved CMJ height by 11 ± 13%. During the CMJ, VL's MTU and series elastic element (SEE) length changes and velocities increased from baseline to post‐test, but VL's fascicle length change and velocity did not significantly change. It is speculated that altered lower limb coordination and increased force output of the lower limb muscles during the CMJ allowed more energy to be stored within VL's SEE. This may have contributed to enhanced VL MTU work during the propulsion phase and an improved CMJ performance following combined ballistic training. [ABSTRACT FROM AUTHOR]

Acute increases in tendon blood flow and oxygenation after stress (i.e., hyperemic response) can enhance tendon recovery. While loading intensity is a fundamental part of resistance training programs, its effects on tendon's hyperemic response are unknown. This study aimed to compare acute changes in total (total hemoglobin [THb]) and oxygenated hemoglobin (HbO2) concentrations in the patellar tendon after isometric exercise at different intensities. Thirteen participants performed 8 (5 s) isometric knee extensions at 25%, 50%, and 75% maximal load (maximal voluntarily isometric contraction [MVIC]), separated by 20 min recovery, prescribed in randomized and counterbalanced order. Changes in patellar tendon THb, HbO2 and deoxygenated hemoglobin (HHb) in response to exercise at each intensity were measured using near‐infrared spectroscopy. Post‐exercise, HbO2 increased with 50% (ηp2 = 0.305, f = 5.26, p < 0.01) and 75% (ηp2 = 0.245, f = 4.56, p < 0.01) but not 25% (ηp2 = 0.088, f = 1.16, p = 0.339) MVIC, while THb increased in 50% (ηp2 = 0.305, f = 5.26, p = 0.01) but not 25% (ηp2 = 0.067, f = 0.865, p = 0.51) or 75% (ηp2 = 0.126, f = 1.729, p = 0.14) MVIC. Additionally, increasing load from 25% to 50% MVIC resulted in greater THb (f = 2.459, p = 0.43), HbO2 (f = 3.389, p = 0.13) and HHb (f = 0.320, p = 0.01) post‐exercise responses, but no differences were observed between 50% and 75% MVIC (THb: f = 0.748, p = 0.59; HbO2: f = 0.825, p = 0.54; HHb: f = 0.713, p = 0.62). Our results suggest there is a loading threshold at ~50% MVIC at which the tendon hyperemic response is fully achieved. Training above this intensity is not expected to provide any additional change to the tendon microvascular response. Therefore, moderate loading seems to be sufficient to fully elicit the patellar tendon hyperemic response that's believed to stimulate tendon healing. [ABSTRACT FROM AUTHOR]

Objective: Several tissues produce and release interleukin‐6 (IL‐6) in response to beta2‐adrenergic stimulation with selective agonists (beta2‐agonists). Moreover, exercise stimulates muscle IL‐6 production, but whether beta2‐agonists regulate skeletal muscle production and release of IL‐6 in humans in association with exercise remains to be clarified. Thus, we investigated leg IL‐6 release in response to beta2‐agonist salbutamol in lean young men at rest and in recovery from resistance exercise. Design: The study employed a randomized controlled crossover design, where 12 men ingested either salbutamol (16 mg) or placebo for 4 days, followed by the last dose (24 mg) administered 1½ h before exercise. Arterial and femoral venous plasma IL‐6 as well as femoral artery blood flow was measured before and ½–5 h in recovery from quadriceps muscle resistance exercise. Furthermore, vastus lateralis muscle biopsies were collected ½ and 5 h after exercise for determination of mRNA levels of IL‐6 and Tumor Necrosis Factor (TNF)‐α. Results: Average leg IL‐6 release was 1.7‐fold higher (p = 0.01) for salbutamol than placebo, being 138 ± 76 and 79 ± 66 pg min−1 (mean ± SD) for salbutamol and placebo, respectively, but IL‐6 release was not significantly different between treatments within specific sampling points at rest and after exercise. Muscle IL‐6 mRNA was 1.5‐ and 1.7‐fold higher (p = 0.001) for salbutamol than placebo ½ and 5 h after exercise, respectively, whereas no significant treatment differences were observed for TNF‐α mRNA. Conclusions: Beta2‐adrenergic stimulation with high doses of the selective beta2‐agonist salbutamol, preceeded by 4 consecutive daily doses, induces transcription of IL‐6 in skeletal muscle in response to resistance exercise, and increases muscle IL‐6 release in lean individuals. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the effect of specific collagen peptides (SCP) combined with resistance training (RT) on changes in tendinous and muscular properties. In a randomized, placebo‐controlled study, 40 healthy male volunteers (age: 26.3 ± 4.0 years) completed a 14 weeks high‐load resistance training program. One group received a daily dosage of 5g SCP while the other group received 5g of a placebo (PLA) supplement. Changes in Achilles tendon cross‐sectional area (CSA), tendon stiffness, muscular strength, and thickness of the plantar flexors were measured. The SCP supplementation led to a significantly (p = 0.002) greater increase in tendon CSA (+11.0%) compared with the PLA group (+4.7%). Moreover, the statistical analysis revealed a significantly (p = 0.014) greater increase in muscle thickness in the SCP group (+7.3%) compared with the PLA group (+2.7%). Finally, tendon stiffness and muscle strength increased in both groups, with no statistical difference between the groups. In conclusion, the current study shows that the supplementation of specific collagen peptides combined with RT is associated with a greater hypertrophy in tendinous and muscular structures than RT alone in young physically active men. These effects might play a role in reducing tendon stress (i.e., deposition of collagen in load‐bearing structures) during daily activities. [ABSTRACT FROM AUTHOR]

Knowledge about muscular forces and fascicle behavior during hamstring exercises can optimize exercise prescription, but information on these outcomes across different exercises is lacking. We aimed to characterize and compare lower‐limb muscle forces and biceps femoris long head muscle fascicle behavior between three hamstring exercises: the Nordic hamstring curl (NHC), single‐leg Roman chair (RCH), and single‐leg deadlift (DL). Ten male participants performed the exercises while full‐body kinematics, ground reaction forces, surface muscle activation, and biceps femoris long head fascicle behavior were measured. Mean fascicle length was highest in the DL, followed by the RCH and NHC. Fascicle lengthening was higher in the NHC compared with the RCH and DL, with no difference between the RCH and DL. Biceps femoris short and long head, semitendinosus, and semimembranosus peak forces were generally higher in the NHC compared with the RCH and DL, while mean forces during the eccentric phase were generally not different between the NHC and RCH. Peak forces in the NHC coincided with low biceps femoris long head and semimembranosus muscle activation. The NHC generally has the highest peak hamstring muscle forces and results in more fascicle lengthening when compared to the DL and RCH. The NHC may therefore be most effective to promote increases in fascicle length. While the NHC may be effective to promote biceps femoris short head and semitendinosus strength adaptations, the RCH and DL may be more effective to promote strength increases in the biceps femoris long head and semimembranosus. [ABSTRACT FROM AUTHOR]

We aimed to investigate whether muscle fiber cross‐sectional area (fCSA) and associated molecular processes could be differently affected at the group and individual level by manipulating resistance training (RT) variables. Twenty resistance‐trained subjects had each leg randomly allocated to either a standard RT (RT‐CON: without specific variables manipulations) or a variable RT (RT‐VAR: manipulation of load, volume, muscle action, and rest interval at each RT session). Muscle fCSA, satellite cell (SC) pool, myonuclei content, and gene expression were assessed before and after training (chronic effect). Gene expression was assessed 24 h after the last training session (acute effect). RT‐CON and RT‐VAR increased fCSA and myonuclei domain in type I and II fibers after training (p < 0.05). SC and myonuclei content did not change for both conditions (p > 0.05). Pax‐7, MyoD, MMP‐2 and COL3A1 (chronic) and MGF, Pax‐7, and MMP‐9 (acute) increased similar for RT‐CON and RT‐VAR (p < 0.05). The increase in acute MyoG expression was significantly higher for the RT‐VAR than RT‐CON (p < 0.05). We found significant correlation between RT‐CON and RT‐VAR for the fCSA changes (r = 0.89). fCSA changes were also correlated to satellite cells (r = 0.42) and myonuclei (r = 0.50) changes. Heatmap analyses showed coupled changes in fCSA, SC, and myonuclei responses at the individual level, regardless of the RT protocol. The high between and low within‐subject variability regardless of RT protocol suggests that the intrinsic biological factors seem to be more important to explain the magnitude of fCSA gains in resistance‐trained subjects. [ABSTRACT FROM AUTHOR]

The article presents a study which examined the relationships between maximal strength, sprint, physical high-intensity match-play performance and countermovement jump (CMJ) among elite female football players. The performances were assessed in terms of total distance covered, high-intensity running distance, and sprinting distance, as well as the methods used like Shapiro-Wilk normality test and Pearson's correlation coefficients.

The purpose of this cross-sectional study was to compare explosive strength and underpinning contractile, hypertrophic, and neuromuscular activation characteristics of long-term maximum strength-trained (LT-MST; ie, ≥3 years of consistent, regular knee extensor training) and untrained individuals. Sixty-three healthy young men (untrained [UNT] n = 49, and LT-MST n = 14) performed isometric maximum and explosive voluntary, as well as evoked octet knee extension contractions. Torque, quadriceps, and hamstring surface EMG were recorded during all tasks. Quadriceps anatomical cross-sectional area (QACSAMAX; via MRI) was also assessed. Maximum voluntary torque (MVT; +66%) and QACSAMAX (+54%) were greater for LT-MST than UNT ([both] p < 0.001). Absolute explosive voluntary torque (25–150 ms after torque onset; +41 to +64%; [all] p < 0.001; 1.15≤ effect size [ES]≤2.36) and absolute evoked octet torque (50 ms after torque onset; +43, p < 0.001; ES = 3.07) were greater for LT-MST than UNT. However, relative (to MVT) explosive voluntary torque was lower for LT-MST than UNT from 100 to 150 ms after contraction onset (−11% to −16%; 0.001 ≤ p ≤ 0.002; 0.98 ≤ ES ≤ 1.11). Relative evoked octet torque 50 ms after onset was lower (−10%; p < 0.001; ES = 1.14) and octet time to peak torque longer (+8%; p = 0.001; ES = 1.18) for LT-MST than UNT indicating slower contractile properties, independent from any differences in torque amplitude. The greater absolute explosive strength of the LT-MST group was attributable to higher evoked explosive strength, that in turn appeared to be due to larger quadriceps muscle size, rather than any differences in neuromuscular activation. In contrast, the inferior relative explosive strength of LT-MST appeared to be underpinned by slower intrinsic/ evoked contractile properties. [ABSTRACT FROM AUTHOR]

Purpose: We investigated the effects of three different unilateral isoinertial resistance training protocols with eccentric overload on changes in lean mass and muscle function of trained (TL) and contralateral non-trained (NTL) legs. Methods: Physically active university students were randomly assigned to one of three training groups or a control group (n = 10/group). Participants in the training groups performed dominant leg isoinertial squat training twice a week for 6 weeks (4 sets of 7 repetitions) using either an electric-motor device with an eccentric phase velocity of 100% (EM100) or 150% (EM150) of concentric phase velocity or a conventional flywheel device (FW) with the same relative inertial load. Changes in thigh lean mass, unilateral leg-press one-repetition maximum (1-RM), muscle power at 40–80% 1-RM, and unilateral vertical jump height before and after training were compared between the groups and between TL and NTL. Results: No changes in any variable were found for the control group. In TL, all training groups showed similar increases (p < 0.05) in 1-RM strength (22.4–30.2%), lean tissue mass (2.5–5.8%), muscle power (8.8–21.7%), and vertical jump height (9.1–32.9%). In NTL, 1-RM strength increased 22.0–27.8% without significant differences between groups; however, increases in lean mass (p < 0.001) were observed for EM150 (3.5%) and FW (3.8%) only. Unilateral vertical jump height (6.0–32.9%) and muscle power (6.8–17.5%) also increased in NTL without significant differences between training groups. Conclusion: The three eccentric-overload resistance training modalities produced similar neuromuscular changes in both the trained and non-trained legs, suggesting that strong cross-education effects were induced by the eccentric-overload training. [ABSTRACT FROM AUTHOR]

This review aimed to conduct a meta-analysis of studies examining the effects of caffeine on rate of force development (RFD). Ten databases were searched to find relevant studies. Risk of bias (RoB) of the included studies was evaluated. Data were analyzed in a random-effects meta-analysis. Eleven studies with “some concerns” regarding RoB were included. In the main meta-analysis, there was a significant ergogenic effect of caffeine ingestion on RFD (Hedges’ g = 0.37; 95% confidence interval [CI]: 0.21, 0.52; p < 0.0001). An ergogenic effect of caffeine was also found on RFD during resistance exercises (Hedges’ g = 0.49; 95% CI: 0.30, 0.67; p < 0.0001), but not during the countermovement jump test (Hedges’ g = 0.18; 95% CI: –0.02, 0.39; p = 0.08), with a significant difference between the subgroups (p = 0.03). Small-to- moderate (3–5 mg/kg; Hedges’ g = 0.25; 95% CI: 0.09, 0.41; p = 0.002) and moderate-to- high caffeine doses (6–10 mg/kg) enhanced RFD (Hedges’ g = 0.57; 95% CI: 0.30, 0.85; p < 0.0001), even though the effects were larger with higher caffeine doses (p = 0.04). Overall, caffeine ingestion increases RFD, which is relevant given that RFD is commonly associated with sport-specific tasks. From a practical perspective: (1) individuals interested in the acute enhancement of RFD in resistance exercise may consider supplementing with caffeine; and (2) given that evaluation of RFD is most commonly used for testing purposes, caffeine ingestion (3–10 mg/kg 60 min before exercise) should be standardized before RFD assessments. [ABSTRACT FROM AUTHOR]

This parallel‐group randomized controlled trial investigated the effect of concurrent strength and endurance (CSE) training on running performance, biomechanics, and muscle activity during overground running. Thirty moderately trained distance runners were randomly assigned to 10‐week CSE training (n = 15; 33.1 ± 7.5 years) or a control group (n = 15; 34.2 ± 8.2 years). Participants ran ≥30 km per week and had no experience with strength training. The primary outcome measure was 2‐km run time. Secondary outcome measures included lower limb sagittal plane biomechanics and muscle activity during running (3.89 m s−1 and maximal sprinting); maximal aerobic capacity (V̇O2max); running economy; and body composition. CSE training improved 2‐km run time (mean difference (MD): −11.3 s [95% CI −3.7, −19.0]; p = 0.006) and time to exhaustion during the V̇O2max running test (MD 59.1 s [95% CI 8.58, 109.62]; p = 0.024). The CSE training group also reduced total body fat (MD: −1.05 kg [95% CI −0.21, −1.88]; p = 0.016) while total body mass and lean body mass were unchanged. Hip joint angular velocity during the early swing phase of running at 3.89 m s−1 was the only biomechanical or muscle activity variable that significantly changed following CSE training. CSE training is beneficial for running performance, but changes in running biomechanics and muscle activity may not be contributing factors to the performance improvement. Future research should consider other possible mechanisms and the effect of CSE training on biomechanics and muscle activity during prolonged running under fatigued conditions. [ABSTRACT FROM AUTHOR]

This study aimed to determine the specific adaptations provoked by power‐oriented resistance training using light (LL‐PT, 40% 1‐RM) vs. heavy (HL‐PT, 80% 1‐RM) loads in older adults. Using a randomized within‐subject study design, 45 older adults (>65 years) completed an 8‐week control period (CTR) followed by 12 weeks of unilateral LL‐PT vs. HL‐PT on a leg press. The 1‐RM, theoretical force at zero velocity (F0), maximal unloaded velocity (V0), and maximal muscle power (Pmax) were determined through a force‐velocity relationship test. Isometrically, the rate of force development (RFD) and the corresponding muscle excitation of the knee extensor muscles were assessed. In addition, muscle cross‐sectional area (CSA) and architecture of two quadriceps muscles were determined. Changes after CTR, LL‐PT and HL‐PT were compared using linear mixed models. HL‐PT provoked greater improvements in 1‐RM and F0 (effect size (ES) = 0.55‒0.68; p < 0.001) than those observed after LL‐PT (ES = 0.27−0.47; p ≤ 0.001) (post hoc treatment effect, p ≤ 0.057). By contrast, ES of changes in V0 was greater in LL‐PT compared to HL‐PT (ES = 0.71, p < 0.001 vs. ES = 0.39, p < 0.001), but this difference was not statistically significant. Both power training interventions elicited a moderate increase in Pmax (ES = 0.65‒0.69, p < 0.001). Only LL‐PT improved early RFD (ie, ≤100 ms) and muscle excitation (ES = 0.36‒0.60, p < 0.05). Increased CSA were noted after both power training programs (ES = 0.13‒0.35, p < 0.035), whereas pennation angle increased only after HL‐PT (ES = 0.37, p = 0.004). In conclusion, HL‐PT seems to be more effective in improving the capability to generate large forces, whereas LL‐PT appears to trigger greater gains in movement velocity in older adults. However, both interventions promoted similar increases in muscle power as well as muscle hypertrophy. [ABSTRACT FROM AUTHOR]

Non‐physiological sources may lead to equivocal interpretation on the degree of muscle excitation from electromyograms (EMGs) amplitude. This presumably explains the contradictory findings regarding the effect of the bench press inclination on the pectoralis major (PM) activation pattern. To contend with these issues, herein we used high‐density surface EMG to investigate whether different PM regions are excited during the flat and 45° inclined bench press exercises. Single‐differential EMGs were collected from 15 regions along the PM cranio‐caudal axis, while 8 volunteers performed a set of the flat and 45° inclined bench press at 50% and 70% of 1 repetition maximum. The coefficient of variation, the range of motion, and the cycle duration were calculated from the barbell vertical position to assess the within‐subject consistency across cycles. The number of channels detecting the largest EMGs amplitude (active channels), their interquartile range, and their barycentre coordinate were assessed to characterize the EMG amplitude distribution within PM. No significant differences in the range of motion (p > 0.11), cycle duration (p > 0.28), number of active channels (p > 0.05), and interquartile range of active channels (p > 0.39) were observed between the two bench press inclinations. Conversely, the barycentre shifted toward the PM clavicular region (p < 0.001) when the bench press changed from flat to 45°. Our results revealed that greatest EMG amplitudes were concentrated at the PM sternocostal and clavicular heads when exercising in the flat and 45° inclined bench press, respectively. Performing the bench press exercise, with different postures, seem to demand the excitation of different PM regions. [ABSTRACT FROM AUTHOR]

Sporadic inclusion body myositis (sIBM) is an idiopathic inflammatory muscle disease associated with skeletal muscle inflammation and a parallel progressive decline in muscle strength and physical function. Eventually, most sIBM patients require use of wheelchair after about 10 years of diagnosis and assistance to perform activities of daily living. This study presents data from a randomized controlled intervention trial (NCT02317094) that examined the effect of 12 weeks low‐load blood‐flow restricted (BFR) resistance training on maximal muscle strength, power, rate of force development (RFD), thigh lean mass (TLM), and voluntary muscle activation (VA) in sIBM patients. A time‐by‐group interaction in knee extensor strength was observed in the stronger leg (p ≤ 0.033) but not the weaker leg. Within‐group changes were observed with BFR training (BFR) manifested by increased knee extensor strength in the strongest leg (+13.7%, p = 0.049), whereas non‐exercising patients (CON) showed reduced knee extensor strength (−7.7%, p = 0.018). Maximal leg extensor power obtained for the stronger leg remained unchanged following BFR training (+9.5%, p = 0.37) while decreasing in CON (−11.1%, p = 0.05). No changes in TLM were observed. VA declined post‐training (p = 0.037) in both BFR (−6.3% points) and CON (−7.5% points). The present data indicate that BFR resistance training can attenuate the rate of decline in mechanical muscle function typically experienced by sIBM patients. The preservation of muscle mass and mechanical muscle function with BFR resistance training may be considered of high clinical importance in sIBM patients to countermeasure the disease‐related decline in physical function. [ABSTRACT FROM AUTHOR]

Short‐term energy deficits impair anabolic hormones and muscle protein synthesis. However, the effects of prolonged energy deficits on resistance training (RT) outcomes remain unexplored. Thus, we conducted a systematic review of PubMed and SportDiscus for randomized controlled trials performing RT in an energy deficit (RT+ED) for ≥3 weeks. We first divided the literature into studies with a parallel control group without an energy deficit (RT+CON; Analysis A) and studies without RT+CON (Analysis B). Analysis A consisted of a meta‐analysis comparing gains in lean mass (LM) and strength between RT+ED and RT+CON. Studies in Analysis B were matched with separate RT+CON studies for participant and intervention characteristics, and we qualitatively compared the gains in LM and strength between RT+ED and RT+CON. Finally, Analyses A and B were pooled into a meta‐regression examining the relationship between the magnitude of the energy deficit and LM. Analysis A showed LM gains were impaired in RT+ED vs RT+CON (effect size (ES) = −0.57, p = 0.02), but strength gains were comparable between conditions (ES = −0.31, p = 0.28). Analysis B supports the impairment of LM in RT+ED (ES: −0.11, p = 0.03) vs RT+CON (ES: 0.20, p < 0.001) but not strength (RT+ED ES: 0.84; RT+CON ES: 0.81). Finally, our meta‐regression demonstrated that an energy deficit of ~500 kcal · day−1 prevented gains in LM. Individuals performing RT to build LM should avoid prolonged energy deficiency, and individuals performing RT to preserve LM during weight loss should avoid energy deficits >500 kcal day−1. [ABSTRACT FROM AUTHOR]

Beneficial acute effects of resistance exercise on cognitive functions may be modified by exercise intensity or by habitual physical activity. Twenty‐six participants (9 female and 17 male; 25.5 ± 3.4 years) completed four resistance exercise interventions in a randomized order on separate days (≥48 h washout). The intensities were set at 60%, 75%, and 90% of the one repetition maximum (1RM). Three interventions had matched workloads (equal resistance*nrepetitions). One intervention applied 75% of the 1RM and a 50% reduced workload (resistance*nrepetitions = 50%). Cognitive attention (Trail Making Test A—TMTA), task switching (Trail Making Test B—TMTB), and working memory (Digit Reading Spans Backward) were assessed before and immediately after exercise. Habitual activity was assessed as MET hours per week using the International Physical Activity Questionnaire. TMTB time to completion was significantly shorter after exercise with an intensity of 60% 1RM and 75% 1RM and 100% workload. Friedman test indicated a significant effect of exercise intensity in favor of 60% 1RM. TMTA performance was significantly shorter after exercise with an intensity of 60% 1RM, 90% 1RM, and 75% 1RM (50% workload). Habitual activity with vigorous intensity correlated positively with the baseline TMTB and Digit Span Forward performance but not with pre‐ to post‐intervention changes. Task switching, based on working memory, mental flexibility, and inhibition, was beneficially influenced by acute exercise with moderate intensity whereas attention performance was increased after exercise with moderate and vigorous intensity. The effect of regular activity had no impact on acute exercise effects. [ABSTRACT FROM AUTHOR]

Resistance exercises eliciting eccentric overload (EO) are considered to strongly promote muscular hypertrophy and broad neuromuscular adaptations but typically require specialized equipment. The aims of these experiments were to assess whether EO is achieved during common high‐speed stretch‐shortening cycle (SSC) exercises (rebound bench press throw [RBPT] and squat jump [SJ]), and to test the effect of the external load on the EO achieved. Twenty‐nine under 18 handball players and fifteen physically active males (24.9 ± 3.2 years) took part in the experiments. Testing consisted of a single set of 6 repetitions with light (25%–30% 1‐RM), moderate (50% 1‐RM), and heavy (70%–75% 1‐RM) loads. Eccentric and concentric force near the zero‐velocity point (50–200 ms) as well as eccentric‐concentric force ratio (EO; %) were calculated. In RBPT, higher EO values were found at 50% 1‐RM than 70% 1‐RM in the time interval 50 ms before and after the zero‐velocity point. Higher EO values were also found at 50% 1‐RM than both 30% 1‐RM and 70% 1‐RM 100 ms before and after the zero‐velocity point. For the SJ, higher EO values were found at 50% 1‐RM and 75% 1‐RM than 25% 1‐RM 100 ms before and after the zero‐velocity point. Higher EO values were found at 50% 1‐RM than 25% 1‐RM 200 ms before and after the zero‐velocity point. However, the higher EO values in the SJ were found far from the zero‐velocity point. High‐speed SSC resistance training provides similar EO to other methods and thus should promote muscle hypertrophy and other neuromuscular adaptations. [ABSTRACT FROM AUTHOR]

Background: Colorectal cancer (CRC) is a common cancer worldwide, with increasing numbers surviving and living with long‐term side effects from treatment. Physical exercise during or after treatment may have several beneficial effects, but knowledge of CRC patients' reflections on exercising during adjuvant therapy is limited. The aim of this study was to explore the experiences of CRC patients participating in a supervised exercise program during adjuvant chemotherapy. Methods: This study included CRC patients participating in two intervention studies with individually tailored and supervised combinations of endurance, resistance, and balance exercises during adjuvant chemotherapy. Semi‐structured interviews performed at the beginning, during, and immediately after the intervention period from 15 participants were analyzed using thematic analysis. Results: Four main themes identified were "structuring life with cancer," "motivation to exercise," "training experiences," and "effects of exercise." Scheduled appointments gave structure to daily life and served as an external motivational factor. The individual adjustments of exercise gave a sense of security and helped improving adherence, especially when feeling depressed or fatigued. Common expectations were improvement of endurance and strength and counteracting negative effects of chemotherapy. Experienced positive effects from exercising, both mentally and physically, contributed to inner motivation and inspired continued exercising after the study period. Conclusion: This study offers important insights into CRC patients' experiences of participating in a physical exercise program during adjuvant chemotherapy. Based on our findings, we recommend supervised and individually tailored physical exercise during adjuvant chemotherapy to this patient group. [ABSTRACT FROM AUTHOR]

Conducting field‐based strength assessments is embedded within football academy development processes. Yet, there is a limited understanding of how hip and groin strength assessments relate to vital game‐based tasks such as sprinting and change of direction (COD) performance. Our aim was to explore field‐based strength assessments and their relationships with both sprint and COD performance in male academy footballers. Participants (n = 146; age 14.2 ± 2.2 years; stature 166.3 ± 15.4 cm; body mass 55.6 ± 15.6 kg) performed maximal countermovement jump (CMJ), Nordic hamstring strength (NHS), isometric hip adductor (ADD)/abductor (ABD), 5 m, 10 m, 20 m sprints, and modified 505 agility test. All strength measures were allometrically scaled to account for body weight. Between‐limb differences were reported as imbalance scores. Principal component analysis reduced sprint and COD variables to a single "running ability" component score. Scaled strength and imbalance, when controlled for age, were associated with "running ability" (adjusted R2 = 0.78, p < 0.001). Significant effects on "running ability" included the following: age, CMJ impulse, NHS, and hip‐ADD. When the sprint and COD variables were explored independently, age and CMJ‐impulse were featured in all sprint and COD models. For 10 m and 20 m sprint distances, hip‐ADD emerged as a significant effect. Mean 505 performance was explained by age, CMJ‐impulse, hip‐ADD, but also with the addition of NHS. Our findings suggest that insight into the underpinning strength qualities of "running ability" of academy footballers can be obtained from a suite of field‐based tests. [ABSTRACT FROM AUTHOR]

The current study aimed: (i) to external validate total body water (TBW) and extracellular water (ECW) derived from athlete and non-athlete predictive equations using radioisotope dilution techniques as a reference criterion in male and female athletes; (ii) in a larger sample, to determine the agreement between specific and generalized equations when estimating body fluids in male and female athletes practicing different sports. A total of 1371 athletes (men: n = 921, age 23.9 ± 1.4 y; women: n = 450, age 27.3 ± 6.8 y) participated in this study. All athletes underwent bioelectrical impedance analyses, while TBW and ECW were assessed with dilution techniques in a subgroup of 185 participants (men: n = 132, age 21.7 ± 5.1 y; women: n = 53, age 20.3 ± 4.5 y). Two specific and eight generalized predictive equations were tested. Compared to the criterion methods, no mean bias was observed using the athlete-specific equations for TBW and ECW (-0.32 to 0.05, p > 0.05) and the coefficient of determination ranged from R² = 0.83 to 0.94. The majority of the generalized predictive equations underestimated TBW and ECW (p < 0.05); R² ranged from 0.66 to 0.89. In the larger sample, all the generalized equations showed lower TBW and ECW values (ranging from -6.58 to -0.19, p < 0.05) than specific predictive equations; except for TBW in female power/velocity (one equation) athletes and team sport (two equations). The use of generalized BIA-based equations leads to an underestimation of TBW, and ECW compared to athlete-specific predictive equations. Additionally, the larger sample indicates that generalized equations overall provided lower TBW and ECW compared to the athlete-specific equations. [ABSTRACT FROM AUTHOR]

Background: Nowadays, there is a lack of consensus and high controversy about the most effective range of motion (ROM) to minimize the risk of injury and maximize the resistance training adaptations. Objective: To conduct a systematic review and meta‐analysis of the scientific evidence examining the effects of full and partial ROM resistance training interventions on neuromuscular, functional, and structural adaptations. Methods: The original protocol (CRD42020160976) was prospectively registered in the PROSPERO database. Medline, Scopus, and Web of Science databases were searched to identify relevant articles from the earliest record up to and including March 2021. The RoB 2 and GRADE tools were used to judge the level of bias and quality of evidence. Meta‐analyses were performed using robust variance estimation with small‐sample corrections. Results: Sixteen studies were finally included in the systematic review and meta‐analyses. Full ROM training produced significantly greater adaptations than partial ROM on muscle strength (ES = 0.56, p = 0.004) and lower‐limb hypertrophy (ES = 0.88, p = 0.027). Furthermore, although not statistically significant, changes in functional performance were maximized by the full ROM training (ES = 0.44, p = 0.186). Finally, no significant superiority of either ROM was found to produce changes in muscle thickness, pennation angle, and fascicle length (ES = 0.28, p = 0.226). Conclusion: Full ROM resistance training is more effective than partial ROM to maximize muscle strength and lower‐limb muscle hypertrophy. Likewise, functional performance appears to be favored by the use of full ROM exercises. On the contrary, there are no large differences between the full and partial ROM interventions to generate changes in muscle architecture. [ABSTRACT FROM AUTHOR]

We used a within‐subject, cross‐over design study to compare the impact of 4‐weeks' resistance (RT) versus endurance (END) training on vascular function. We subsequently explored the association of intra‐individual effects of RT versus END on vascular function with a single nucleotide polymorphism (SNP) of the NOS3 gene. Thirty‐five healthy males (21 ± 2 years old) were genotyped for the NOS3 rs2070744 SNP and completed both training modalities. Participants completed 12 sessions over a 4‐week period, either RT (leg‐extension) or END (cycling) training in a randomized, balanced cross‐over design with a 3‐week washout period. Participants performed peak oxygen uptake (peak VO2) and leg‐extension single‐repetition maximum (1‐RM) testing, and vascular function assessment using flow‐mediated dilation (FMD) on 3 separated days pre/post‐training. Peak VO2 increased after END (p < 0.001), while 1‐RM increased after RT (p < 0.001). FMD improved after 4‐weeks' training (time effect: p = 0.006), with no difference between exercise modalities (interaction effect: p = 0.92). No relation was found between individual changes (delta, pre‐post) in FMD to both types of training (R2 = 0.06, p = 0.14). Intra‐individual changes in FMD following END and RT were associated with the NOS3 SNP, with TT homozygotes significantly favoring only END (p = 0.016) and TC/CC tending to favor RT only (p = 0.056). Although both training modes improved vascular function, significant intra‐individual variation in the adaptation of FMD was found. The association with NOS3 genotype suggests a genetic predisposition to FMD adapting to a specific mode of chronic exercise. This study therefore provides novel evidence for personalized exercise training to optimize vascular health. [ABSTRACT FROM AUTHOR]

This study aimed to compare the effects of three resistance training (RT) programs differing in the magnitude of velocity loss (VL) allowed in each exercise set: 10%, 30%, or 45% on changes in strength, vertical jump, sprint performance, and EMG variables. Thirty‐three young men were randomly assigned into three experimental groups (VL10%, VL30%, and VL45%; n = 11 each) that performed a velocity‐based RT program for 8 weeks using only the full squat exercise (SQ). Training load (55–70% 1RM), frequency (2 sessions/week), number of sets (3), and inter‐set recovery (4 min) were identical for all groups. Running sprint (20 m), countermovement jump (CMJ), 1RM, muscle endurance, and EMG during SQ were assessed pre‐ and post‐training. All groups showed significant (VL10%: 6.4–58.6%; VL30%: 4.5–66.2%; VL45%: 1.8–52.1%; p < 0.05–0.001) improvements in muscle strength and muscle endurance. However, a significant group × time interaction (p < 0.05) was observed in CMJ, with VL10% showing greater increments (11.9%) than VL30% and VL45%. In addition, VL10% resulted in greater percent change in sprint performance than the other two groups (VL10%: −2.4%; VL30%: −1.8%; and VL45%: −0.5%). No significant changes in EMG variables were observed for any group. RT with loads of 55–70% 1RM characterized by a low‐velocity loss (VL10%) provides a very effective and efficient training stimulus since it yields similar strength gains and greater improvements in sports‐related neuromuscular performance (jump and sprint) compared to training with higher velocity losses (VL30%, VL45%). These findings indicate that the magnitude of VL reached in each exercise set considerably influences the observed training adaptations. [ABSTRACT FROM AUTHOR]

Rehabilitation is an important treatment for non‐insertional Achilles tendinopathy. To date, eccentric loading exercises (ECC) have been the predominant choice; however, mechanical evidence underlying their use remains unclear. Other protocols, such as heavy slow resistance loading (HSR), have shown comparable outcomes, but with less training time. This study aims to identify the effect of external loading and other variables that influence Achilles tendon (AT) force in ECC and HSR. Ground reaction force and kinematic data during ECC and HSR were collected from 18 healthy participants for four loading conditions. The moment arms of the AT were estimated from MRIs of each participant. AT force then was calculated using the ankle torque obtained from inverse dynamics. In the eccentric phase, the AT force was not larger than in the concentric phase in both ECC and HSR. Under the same external load, the force through the AT was larger in ECC with the knee bent than in HSR with the knee straight due to increased dorsiflexion angle of the ankle. Multivariate regression analysis showed that external load and maximum dorsiflexion angle were significant predictors of peak AT force in both standing and seated positions. Therefore, to increase the effectiveness of loading the AT, exercises should apply adequate external load and reach maximum dorsiflexion during the movement. Peak dorsiflexion angle affected the AT force in a standing position at twice the rate of a seated position, suggesting standing could prove more effective for the same external loading and peak dorsiflexion angle. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to compare the effects of short‐term high‐frequency failure vs non‐failure blood flow–restricted resistance exercise (BFRRE) on changes in satellite cells (SCs), myonuclei, muscle size, and strength. Seventeen untrained men performed four sets of BFRRE to failure (Failure) with one leg and not to failure (Non‐failure; 30‐15‐15‐15 repetitions) with the other leg using knee‐extensions at 20% of one repetition maximum (1RM). Fourteen sessions were distributed over two 5‐day blocks, separated by a 10‐day rest period. Muscle samples obtained before, at mid‐training, and 10‐day post‐intervention (Post10) were analyzed for muscle fiber area (MFA), myonuclei, and SC. Muscle size and echo intensity of m.rectus femoris (RF) and m.vastus lateralis (VL) were measured by ultrasonography, and knee extension strength with 1RM and maximal isometric contraction (MVC) up until Post24. Both protocols increased myonuclear numbers in type‐1 (12%–17%) and type‐2 fibers (20%–23%), and SC in type‐1 (92%–134%) and type‐2 fibers (23%–48%) at Post10 (p < 0.05). RF and VL size increased by 5%–10% in both legs at Post10 to Post24, whereas the MFA of type‐1 fibers in Failure was decreased at Post10 (−10 ± 16%; p = 0.02). Echo intensity increased by ~20% in both legs during Block1 (p < 0.001) and was ~8 to 11% below baseline at Post24 (p = 0.001–0.002). MVC and 1RM decreased by 5%–10% after Block1, but increased in both legs by 6%–11% at Post24 (p < 0.05). In conclusion, both short‐term high‐frequency failure and non‐failure BFRRE induced increases in SCs, in myonuclei content, muscle size, and strength, concomitant with decreased echo intensity. Intriguingly, the responses were delayed and peaked 10–24 days after the training intervention. Our findings may shed light on the mechanisms involved in resistance exercise‐induced overreaching and supercompensation. [ABSTRACT FROM AUTHOR]

Gait speed is a measure of health and functioning. Physical and cognitive determinants of gait are amenable to interventions, but best practices remain unclear. We investigated the effects of a 12‐month physical and cognitive training (PTCT) on gait speed, dual‐task cost in gait speed, and executive functions (EFs) compared with physical training (PT) (ISRCTN52388040). Community‐dwelling older adults, who did not meet physical activity recommendations, were recruited (n = 314). PT included supervised walking/balance (once weekly) and resistance/balance training (once weekly), home exercises (2–3 times weekly), and moderate aerobic activity 150 min/week in bouts of >10 min. PTCT included the PT and computer training (CT) on EFs 15–20 min, 3–4 times weekly. The primary outcome was gait speed. Secondary outcomes were 6‐min walking distance, dual‐task cost in gait speed, and EF (Stroop and Trail Making B‐A). The trial was completed by 93% of the participants (age 74.5 [SD3.8] years; 60% women). Mean adherence to supervised sessions was 59%–72% in PT and 62%–77% in PTCT. Home exercises and CT were performed on average 1.9 times/week. Weekly minutes spent in aerobic activities were 188 (median 169) in PT and 207 (median 180) in PTCT. No significant interactions were observed for gait speed (PTCT‐PT, 0.02; 95%CI −0.03, 0.08), walking distance (−3.8; −16.9, 9.3) or dual‐task cost (−0.22; −1.74, 1.30). Stroop improvement was greater after PTCT than PT (−6.9; −13.0, −0.8). Complementing physical training with EFs training is not essential for promotion of gait speed. For EF's, complementing physical training with targeted cognitive training provides additional benefit. [ABSTRACT FROM AUTHOR]

The purpose of the study was to determine if concurrent training (endurance and resistance in a single session) elicits leg muscular adaptations beyond the ones obtained by endurance training alone in sedentary individuals with metabolic syndrome (MetS). Sixty‐six MetS individuals (37% women, age 56 ± 7 years, BMI 32 ± 5 kg m−2 and 3.8 ± 0.8 MetS factors) were randomized to undergo one of the following 16‐week isocaloric exercise programs: (i) 4 + 1 bouts of 4 min at 90% of HRMAX of intense aerobic cycling (IAC + IAC group; n = 33), (ii) 4 IAC bouts followed by 3 sets of 12 repetitions of 3 lower‐limb free‐weight exercises (IAC + RT group; n = 33). We measured the effects of training on maximal cycling power, leg press maximum strength (1RM), countermovement jump height (CMJ), and mean propulsive velocity (MPV) at workloads ranging from 10% to 100% of baseline 1RM leg press. After intervention, MetS components (Z‐score) improved similarly in both groups (p = 0.002). Likewise, maximal cycling power during a ramp test improved similarly in both groups (time effect p < 0.001). However, leg press 1RM improved more in IAC + RT than in IAC + IAC (47 ± 5 vs 13 ± 5 kg, respectively, interaction p < 0.001). CMJ only improved with IAC + RT (0.8 ± 0.2 cm, p = 0.001). Leg press MPV at heavy loads (ie, 80%–100% 1RM) improved more with concurrent training (0.12 ± 0.01 vs 0.06 ± 0.02 m s−1, interaction p = 0.013). In conclusion, in unconditioned MetS individuals, intense aerobic cycling alone improves leg muscle performance. However, substituting 20% of intense aerobic cycling by resistance training further improves 1RM leg press, MPV at high loads, and jumping ability while providing similar improvement in MetS components. [ABSTRACT FROM AUTHOR]

The article discusses the effects of full vs. partial range of motion resistance training interventions on neuromuscular, functional, and structural adaptations has important practical relevance to the field. Topics include reflect the totality of evidence and thus require clarification; and isometric training at longer muscle lengths produced superior increases in muscle size compared to volume-equated training at short muscle lengths.