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Purpose: Uncertainty exists if post-resistance exercise hydrotherapy attenuates chronic inflammatory and hormone responses. The effects of repeated post-resistance exercise water immersion on inflammatory and hormone responses in athletes were investigated., Methods: Male, academy Super Rugby players (n = 18, 19.9 ± 1.5 y, 1.85 ± 0.06 m, 98.3 ± 10.7 kg) participated in a 12-week programme divided into 3 × 4-week blocks of post-resistance exercise water immersion (either, no immersion control [CON]; cold [CWI]; or hot [HWI] water immersion), utilising a randomised cross-over pre-post design. Fasted, morning blood measures were collected prior to commencement of first intervention block, and every fourth week thereafter. Linear mixed-effects models were used to analyse main (treatment, time) and interaction effects., Results: Repeated CWI (p = 0.025, g = 0.05) and HWI (p < 0.001, g = 0.62) reduced creatine kinase (CK), compared to CON. HWI decreased (p = 0.013, g = 0.59) interleukin (IL)-1ra, compared to CON. HWI increased (p < 0.001-0.026, g = 0.06-0.17) growth factors (PDGF-BB, IGF-1), compared to CON and CWI. CWI increased (p = 0.004, g = 0.46) heat shock protein-72 (HSP-72), compared to HWI., Conclusion: Post-resistance exercise CWI or HWI resulted in trivial and moderate reductions in CK, respectively, which may be partly due to hydrostatic effects of water immersion. Post-resistance exercise HWI moderately decreased IL-1ra, which may be associated with post-resistance exercise skeletal muscle inflammation influencing chronic resistance exercise adaptive responses. Following post-resistance exercise water immersion, CWI increased HSP-72 suggesting a thermoregulatory response indicating improved adaptive inflammatory responses to temperature changes, while HWI increased growth factors (PDGF-BB, IGF-1) indicating different systematic signalling pathway activation. Our data supports the continued use of post-resistance exercise water immersion recovery strategies of any temperature during in-season competition phases for improved inflammatory adaptive responses in athletes., (© 2024. The Author(s).)

Both sleep loss and exercise regulate gene expression in skeletal muscle, yet little is known about how the interaction of these stressors affects the transcriptome. The aim of this study was to investigate the effect of nine nights of sleep restriction (SR), with repeated resistance exercise (REx) sessions, on the skeletal muscle transcriptome of young, trained females. Ten healthy females aged 18-35 yr old undertook a randomized cross-over study of nine nights of SR (5 h time in bed) and normal sleep (NS; ≥7 h time in bed) with a minimum 6-wk washout. Participants completed four REx sessions per condition ( days 3 , 5 , 7 , and 9 ). Muscle biopsies were collected both pre- and post-REx on days 3 and 9 . Gene and protein expression were assessed by RNA sequencing and Western blot, respectively. Three or nine nights of SR had no effect on the muscle transcriptome independently of exercise. However, close to 3,000 transcripts were differentially regulated (false discovery rate < 0.05) 48 h after the completion of three resistance exercise sessions in both NS and SR conditions. Only 39% of downregulated genes and 18% of upregulated genes were common between both conditions, indicating a moderating effect of SR on the response to exercise. SR and REx interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested. NEW & NOTEWORTHY This study investigated the effect of nine nights of sleep restriction, with repeated resistance exercise sessions, on the skeletal muscle transcriptome of young, trained females. Sleep restriction and resistance exercise interacted to alter the enrichment of skeletal muscle transcriptomic pathways in young, resistance-trained females. Performing exercise when sleep restricted may not provide the same adaptive response for individuals as if they were fully rested.

Abstract: Horgan, BG, Tee, N, West, NP, Drinkwater, EJ, Halson, SL, Colomer, CME, Fonda, CJ, Tatham, J, Chapman, DW, and Haff, GG. Acute performance, daily well-being and hormone responses to water immersion after resistance exercise in junior international and subelite male volleyball athletes. J Strength Cond Res 37(8): 1643-1653, 2023-Athletes use postexercise hydrotherapy strategies to improve recovery and competition performance and to enhance adaptative responses to training. Using a randomized cross-over design, the acute effects of 3 postresistance exercise water immersion strategies on perceived recovery, neuromuscular performance, and hormone concentrations in junior international and subelite male volleyball athletes ( n = 18) were investigated. After resistance exercise, subjects randomly completed either 15-minute passive control (CON), contrast water therapy (CWT), cold (CWI), or hot water immersion (HWI) interventions. A treatment effect occurred after HWI; reducing perceptions of fatigue (HWI > CWT: p = 0.05, g = 0.43); improved sleep quality, compared with CON ( p < 0.001, g = 1.15), CWI ( p = 0.017, g = 0.70), and CWT ( p = 0.018, g = 0.51); as well as increasing testosterone concentration (HWI > CWT: p = 0.038, g = 0.24). There were trivial to small ( p < 0.001-0.039, g = 0.02-0.34) improvements (treatment effect) in jump performance (i.e., squat jump and countermovement jump) after all water immersion strategies, as compared with CON, with high variability in the individual responses. There were no significant differences (interaction effect, p > 0.05) observed between the water immersion intervention strategies and CON in performance ( p = 0.153-0.99), hormone ( p = 0.207-0.938), nor perceptual ( p = 0.368-0.955) measures. To optimize recovery and performance responses, e.g., during an in-season competition phase, postresistance exercise HWI may assist with providing small-to-large improvements for up to 38 hours in perceived recovery (i.e., increased sleep quality and reduced fatigue) and increases in circulating testosterone concentration. Practitioners should consider individual athlete neuromuscular performance responses when prescribing postexercise hydrotherapy. These findings apply to athletes who aim to improve their recovery status, where postresistance exercise HWI optimizes sleep quality and next-day perceptions of fatigue., (Copyright © 2023 National Strength and Conditioning Association.)

Purpose: Following resistance exercise, uncertainty exists as to whether the regular application of cold water immersion attenuates lean muscle mass increases in athletes. The effects of repeated post-resistance exercise cold versus hot water immersion on body composition and neuromuscular jump performance responses in athletes were investigated., Methods: Male, academy Super Rugby players (n = 18, 19.9 ± 1.5 y, 1.85 ± 0.06 m, 98.3 ± 10.7 kg) participated in a 12-week (4-week × 3-intervention, i.e., control [CON], cold [CWI] or hot [HWI] water immersion) resistance exercise programme, utilising a randomised cross-over pre-post-design. Body composition measures were collected using dual-energy X-ray absorptiometry prior to commencement and every fourth week thereafter. Neuromuscular squat (SJ) and counter-movement jump (CMJ) performance were measured weekly. Linear mixed-effects models were used to analyse main (treatment, time) and interaction effects., Results: There were no changes in lean (p = 0.960) nor fat mass (p = 0.801) between interventions. CON (p = 0.004) and CWI (p = 0.003) increased (g = 0.08-0.19) SJ height, compared to HWI. There were no changes in CMJ height (p = 0.482) between interventions., Conclusion: Repeated post-resistance exercise whole-body CWI or HWI does not attenuate (nor promote) increases in lean muscle mass in athletes. Post-resistance exercise CON or CWI results in trivial increases in SJ height, compared to HWI. During an in-season competition phase, our data support the continued use of post-resistance exercise whole-body CWI by athletes as a recovery strategy which does not attenuate body composition increases in lean muscle mass, while promoting trivial increases in neuromuscular concentric-only squat jump performance., (© 2022. The Author(s).)

Introduction: Female athletes sleep less and report more sleep problems than their male counterparts. Inadequate sleep reduces maximal strength in male athletes; however, little is known about the impact of sleep restriction (SR) on the quantity and quality of resistance exercise performed by female athletes. This study investigated the effect of nine nights of moderate SR on repeated resistance exercise performance, hormonal responses, and perceived fatigue in females., Methods: Ten healthy, resistance-trained, eumenorrheic females age 18-35 yr underwent nine nights of SR (5-h time in bed) and normal sleep (NS; ≥7-h time in bed) in a randomized, crossover fashion with a minimum 6-wk washout. Participants completed four resistance exercise sessions per trial, with blood samples collected before and after exercise. Exercise performance was assessed using volume load, reactive strength index, and mean concentric velocity with rating of perceived exertion recorded after exercise. Participants completed awakening saliva sampling and the Multi-component Training Distress Scale daily., Results: Volume load decreased trivially (<1%, P < 0.05) with SR. Mean concentric velocity per set was slower during SR for the lower-body (up to 15%, P < 0.05), but not the upper-body, compound lifts. Intraset velocity loss was up to 7% greater during SR for back squats ( P < 0.05). SR increased salivary cortisol area under the curve (by 42%), total training distress (by 84%), and session perceived exertion (by 11%)., Conclusions: Sustained SR reduces markers of resistance exercise quality (bar velocity) more than quantity (volume load) and increases perceived effort at the same relative intensity in resistance-trained females. Markers of exercise quality and internal load may be more sensitive than volume load, to advise coaches to the decline in lifting performance for female athletes experiencing SR., (Copyright © 2022 by the American College of Sports Medicine.)

Abstract: Dudley, CE, Drinkwater, EJ, and Feros, SA. Different cluster-loading protocols have no effect on intraset and interset power expression. J Strength Cond Res 36(7): 1763-1769, 2022-This study investigated the effect of cluster-loading protocols on changes in hang power clean (HPC) power characteristics. Ten trained weightlifters (7 male, 3 female, HPC 1.28 [M]; 1.03 [F] × body mass) completed 4 experimental protocols in a randomized repeated-measures design. Protocols were traditional, a basic cluster, and 2 undulating clusters. Each protocol comprised 3 sets of 5 HPC repetitions at an average of 70% 1 repetition maximum (RM). The load for undulating cluster protocols ranged between 60 and 80% 1RM. Countermovement jumps (CMJs) were performed before and after each protocol to gauge effect on neuromuscular status. Statistical analysis comprised a one-way repeated measures analysis of variance. Peak power was significantly greater in the fifth repetition of the basic cluster set protocol compared with the traditional set protocol (mean ± SD: 6.6 ± 2.8%, p = 0.043, g = 0.25). Neither undulating load protocol significantly altered set power characteristics compared with basic cluster sets; however, when analyzing repetition data, peak power increased as load increased (and vice versa), indicating the prescribed loads were suboptimal for power expression in this sample. There was no change in CMJ height between protocols. Coaches should prescribe inter-repetition rest to maintain peak power across multiple repetitions and sets. Basic cluster protocols seem to be the most practical choice over undulating cluster protocols because there is no need to adjust load between repetitions., (Copyright © 2020 National Strength and Conditioning Association.)

It is widely believed that lifting heavy loads slowly, but with a conscious intention to move at high velocity, can produce resistance training (RT) adaptations indicative of rapid movements. This study investigated the effects of verbally cued high "intended" movement velocity (HIMV) during RT on neuromuscular and performance outcomes. 20 untrained volunteers (aged 24.2 ± 3.9 years) participated in 3 weeks of knee extension training. Participants were randomly allocated to receive verbal cues focusing on high intended movement velocity, HIMV, or steady and controlled movement, TRAD (traditional training). All other training variables, including actual movement velocity (30° s -1 ), remained constant. Increase in mean power output at 30° s -1 was greater for TRAD than HIMV (76% and 33%, respectively, P = 0.027). There were main effects for time (but no between-group differences) for maximal isometric force (+14%, P = 0.003), peak torque at 180° s -1 (+22%, P = 0.006), peak torque at 30° s -1 (+29%, P < 0.001), 3-repetition maximum (+20%, P < 0.001), and resting corticospinal excitability (+43%, P = 0.017). There were no differences between groups or across time for voluntary activation (P = 0.793), spinal excitability (P = 0.686), or intracortical inhibition (all P > 0.05). HIMV verbal cueing did not produce additional neurophysiological or performance benefits when compared to traditional cueing. Overall, our results demonstrated that verbal cueing did not alter the principle of velocity-specific adaptation. Cueing that increases the duration of maximal effort may be optimal for maximizing average power output at low speeds., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Pattison, KJ, Drinkwater, EJ, Bishop, DJ, Stepto, NK, and Fyfe, JJ. Modulation of countermovement jump-derived markers of neuromuscular function with concurrent vs. single-mode resistance training. J Strength Cond Res 34(6): 1497-1502, 2020-This study assessed changes in countermovement jump (CMJ)-derived markers of neuromuscular function with concurrent training vs. resistance training (RT) alone and determined associations between changes in CMJ parameters and other neuromuscular adaptations (e.g., maximal strength gain). Twenty-three recreationally active men performed 8 weeks of RT alone (RT group, n = 8) or combined with either high-intensity interval training cycling (HIIT + RT group, n = 8) or moderate-intensity continuous cycling (MICT + RT group, n = 7). Maximal strength and CMJ performance were assessed before (PRE), after 4 weeks of training (MID), and >72 hours (maximal strength) or >5-7 days (CMJ performance) after (POST) the training intervention. Improvements in CMJ relative peak force from both PRE to MID and PRE to POST were attenuated for both HIIT + RT (effect size [ES]: -0.44; ±90% confidence limit, ±0.51 and ES: -0.72; ±0.61, respectively) and MICT + RT (ES: -0.74; ±0.49 and ES: -1.25; ±0.63, respectively). Compared with RT alone, the change in the flight time to contraction time ratio (FT:CT) was attenuated from PRE to MID for MICT + RT (ES: -0.38; ±0.42) and from PRE to POST for both MICT + RT (ES: -0.60; ±0.55) and HIIT + RT (ES: -0.75; ±0.30). PRE to POST changes in both CMJ relative peak force and flight time:contraction time (F:C) ratio were also associated with relative 1 repetition maximum leg press strength gain (r = 0.26 and 0.19, respectively). These findings highlight the utility of CMJ testing for monitoring interference to improvements in neuromuscular function with concurrent training.

Background: Cluster sets (CSs) are a popular resistance training (RT) strategy categorised by short rest periods implemented between single or groups of repetitions. However, evidence supporting the effectiveness of CSs on acute intra-session neuromuscular performance is still equivocal., Objective: The objective of this investigation was to determine the efficacy of a single session of CSs to attenuate losses in force, velocity and power compared to traditional set (TS) training., Methods: Screening consisted of a systematic search of EMBASE, Google Scholar, PubMed, Scopus and SPORTDiscus. Inclusion criteria were (1) measured one or more of mean/peak force, velocity or power; (2) implemented CSs in comparison to TSs; (3) an acute design, or part thereof; and (4) published in an English-language, peer-reviewed journal. Raw data (mean ± standard deviation) were extracted from included studies and converted into standardised mean differences (SMDs) and ± 95% confidence intervals (CIs)., Results: Twenty-five studies were used to calculate SMD ± 95% CI. Peak (SMD = 0.815, 95% CI 0.105-1.524, p = 0.024) and mean (SMD = 0.863, 95% CI 0.319-1.406, p = 0.002) velocity, peak (SMD = 0.356, 95% CI 0.057-0.655, p = 0.019) and mean (SMD = 0.692, 95% CI 0.395-0.990, p < 0.001) power, and peak force (SMD = 0.306, 95% CI - 0.028 to 0.584, p = 0.031) favoured CS. Subgroup analyses demonstrated an overall effect for CS across loads (SMD = 0.702, 95% CI 0.548-0.856, p < 0.001), included exercises (SMD = 0.664, 95% CI 0.413-0.916, p < 0.001), experience levels (SMD = 0.790, 95% CI 0.500-1.080, p < 0.001) and CS structures (SMD = 0.731, 95% CI 0.567-0.894, p < 0.001) with no difference within subgroups., Conclusion: CSs are a useful strategy to attenuate the loss in velocity, power and peak force during RT and should be used to maintain neuromuscular performance, especially when kinetic outcomes are emphasised. However, it remains unclear if the benefits translate to improved performance across all RT exercises, between sexes and across the lifespan.

Resistance training is essential for health and performance and confers many benefits such as increasing skeletal muscle mass, increasing strength and power output, and improving metabolic health. Resistance training is a major component of the physical activity guidelines, yet research in female populations is limited. Recent increases in the promotion of, and the participation by, females in sport and exercise, highlight the need for an increase in understanding of evidence-based best practice exercise prescription for females. The aim of this review is to provide an overview of the current research regarding resistance training performance and skeletal muscle adaptation in females, with a focus on the hormonal variables that may influence resistance training outcomes. Findings suggest that the menstrual cycle phase may impact strength, but not skeletal muscle protein metabolism. In comparison, oral contraception use in females may reduce skeletal muscle protein synthesis, but not strength outcomes, when compared to non-users. Future research should investigate the role of resistance training in the maintenance of skeletal muscle protein metabolism during pregnancy, menopause and in athletes experiencing relative energy deficiency in sport. The review concludes with recommendations for researchers to assist them in the inclusion of female participants in resistance training research specifically, with commentary on the most appropriate methods of controlling for, or understanding the implications of, hormonal fluctuations. For practitioners, the current evidence suggests possible resistance training practices that could optimise performance outcomes in females, although further research is warranted.

Delgado, J, Drinkwater, EJ, Banyard, HG, Haff, GG, and Nosaka, K. Comparison between back squat, Romanian deadlift, and barbell hip thrust for leg and hip muscle activities during hip extension. J Strength Cond Res 33(10): 2595-2601, 2019-This study compared muscle activities of vastus lateralis (VL), biceps femoris (BF), and gluteus maximus (GM) during the back squat (SQ), Romanian deadlift (RDL), and barbell hip thrust (BHT) exercises performed with the same load (60 kg) and at one repetition maximum (1RM). Eight men with a minimum of 1 year's lower-body strength training experience performed the exercises in randomized order. Before each exercise, surface electromyography (EMG) was recorded during a maximal voluntary isometric contraction (MVIC) and then used to normalize to each muscle's EMG during each trial. Barbell hip thrust showed higher GM activity than the SQ (effect size [ES] = 1.39, p = 0.038) but was not significantly different from RDL (ES = 0.49, p = 0.285) at 1RM. Vastus lateralis activity at 1RM during the SQ was significantly greater than RDL (ES = 1.36, p = 0.002) and BHT (ES = 2.27, p = 0.009). Gluteus maximus activity was higher during MVIC when compared with the 60 kg load for the SQ (ES = 1.29, p = 0.002) and RDL (ES = 1.16, p = 0.006) but was similar for the BHT (ES = 0.22, p = 0.523). There were no significant differences in GM (ES = 0.35, p = 0.215) and BF activities (ES = 0.16, p = 0.791) between 1RM and MVIC for the SQ. These findings show that the RDL was equally as effective as the BHT for isolating the hip extensors, while the SQ simultaneously activated the hip and knee extensors.

Purpose: The power clean and other weightlifting movements are commonly used in the development of muscle power. However, there is a paucity of research examining the use of the hook grip (HG) in weightlifting performance. Therefore, the purpose of this study was to compare 1-repetition maximum (1RM) and kinetic, kinematic, and qualitative variables across a range of loads (75-100%) during power-clean performance with an HG and a closed grip., Methods: A total of 11 well-trained men (power-clean 1RM = 113.4 [15.9] kg, 1.34 × body mass) with at least 3 mo of HG experience volunteered to participate. Following a familiarization session, 1RM testing with the HG and closed grip were completed 5-7 d apart in a randomized order. Barbell kinetic and kinematic variables were recorded via a force platform and dual linear position transducer system., Results: All subjects had a greater 1RM with the HG than with the closed grip (P < .001, effect size [ES] = 0.43). Peak velocity (ES = 0.41-0.70), peak power (ES = 0.43-0.61), peak force (ES = 0.50-0.57), and catch height (ES = 0.40-0.96) were significantly greater (P < .05) when using the HG at all or most of the submaximal intensities. In addition, subjects reported significantly greater perceptions of grip security, power, and technical competency at submaximal but not maximal loads., Conclusions: Athletes and coaches who implement weightlifting movements in their physical preparation should adopt the HG where possible. Furthermore, researchers and sport scientists should control and report the grip type used when performing weightlifting-type movements.

Oranchuk, DJ, Robinson, TL, Switaj, ZJ, and Drinkwater, EJ. Comparison of the hang high pull and loaded jump squat for the development of vertical jump and isometric force-time characteristics. J Strength Cond Res 33(1): 17-24, 2019-Weightlifting movements have high skill demands and require expert coaching. Loaded jumps have a comparably lower skill demand but may be similarly effective for improving explosive performance. The purpose of this study was to compare vertical jump performance, isometric force, and rate of force development (RFD) after a 10-week intervention using the hang high pull (hang-pull) or trap-bar jump squat (jump-squat). Eighteen National Collegiate Athletic Association Division II swimmers (8 males, 10 females) with at least 1 year of resistance training experience volunteered to participate. Testing included the squat jump (SJ), countermovement jump, and the isometric midthigh pull (IMTP). Vertical ground reaction forces were analyzed to obtain jump height and relative peak power. Relative peak force, peak RFD, and relative force at 5 time bands were obtained from the IMTP. Subjects were randomly assigned to either a hang pull (n = 9) or jump-squat (n = 9) training group and completed a 10-week, volume-equated, periodized training program. Although there was a significant main effect of training for both groups, no statistically significant between-group differences were found (p ≥ 0.17) for any of the dependent variables. However, medium effect sizes in favor of the jump-squat training group were seen in SJ height (d = 0.56) and SJ peak power (d = 0.69). Loaded jumps seem equally effective as weightlifting derivatives for improving lower-body power in experienced athletes. Because loaded jumps require less skill and less coaching expertise than weightlifting, loaded jumps should be considered where coaching complex movements is difficult.

Objectives: Inadequate sleep (e.g., an insufficient duration of sleep per night) can reduce physical performance and has been linked to adverse metabolic health outcomes. Resistance exercise is an effective means to maintain and improve physical capacity and metabolic health, however, the outcomes for populations who may perform resistance exercise during periods of inadequate sleep are unknown. The primary aim of this systematic review was to evaluate the effect of sleep deprivation (i.e. no sleep) and sleep restriction (i.e. a reduced sleep duration) on resistance exercise performance. A secondary aim was to explore the effects on hormonal indicators or markers of muscle protein metabolism., Methods: A systematic search of five electronic databases was conducted with terms related to three combined concepts: inadequate sleep; resistance exercise; performance and physiological outcomes. Study quality and biases were assessed using the Effective Public Health Practice Project quality assessment tool., Results: Seventeen studies met the inclusion criteria and were rated as 'moderate' or 'weak' for global quality. Sleep deprivation had little effect on muscle strength during resistance exercise. In contrast, consecutive nights of sleep restriction could reduce the force output of multi-joint, but not single-joint movements. Results were conflicting regarding hormonal responses to resistance training., Conclusion: Inadequate sleep impairs maximal muscle strength in compound movements when performed without specific interventions designed to increase motivation. Strategies to assist groups facing inadequate sleep to effectively perform resistance training may include supplementing their motivation by training in groups or ingesting caffeine; or training prior to prolonged periods of wakefulness., (Copyright © 2018 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.)

We sought to determine the efficacy of using a continuous time course trial to assess the temporal profile of post-activation potentiation and to determine the time course of potentiation of discrete jump squat kinetic and kinematic variables. Eight physically trained men performed jump squats before and 4, 8, and 12 min after a 5-repetition maximum back squat. Time intervals were assessed in 3 discontinuous trials (each time interval assessed in a separate trial) and in 1 continuous trial (all time intervals assessed in a single trial). Percentage differences between continuous and discontinuous trials at each time interval were mostly insubstantial. Discrete variables displayed a diverse time course (effect size: trivial to large); time to maximal values ranged between 5.00 ± 2.53 min (concentric peak force) and 9.50 ± 2.98 min (eccentric mean force). Eccentric variables (8.58 ± 3.56 min) took longer to peak than concentric variables (6.64 ± 2.93 min) (effect size: small). Individual subjects attained maximal values for kinetic and kinematic variables at different time intervals, yet the 4-min interval typically displayed the greatest magnitude and frequency of potentiation. We conclude that a continuous time course trial does not substantially influence performance of subsequent jumps and is appropriate for determining the temporal profile of potentiation, which is influenced by discrete jump squat kinetic and kinematic variables and individual differences.

Junior basketball athletes require a well-designed resistance training program to improve their physical development. Lack of expert supervision and resistance training in junior development pathways may be overcome by implementing an online video-based program. The aim of this study was to compare the magnitude of improvement (change) in physical performance and strength and functional movement patterns of junior basketball athletes using either a fully supervised or an online video-based resistance training program. Thirty-eight junior basketball athletes (males, n = 17; age, 14 ± 1 year; height, 1.79 ± 0.10 m; mass, 67 ± 12 kg; females, n = 21; age, 15 ± 1 year; height, 1.70 ± 0.07 m; mass, 62 ± 8 kg) were randomly assigned into a supervised resistance training group (SG, n = 13), video training group (VG, n = 13) or control group (CG, n = 12) and participated in a 6-week controlled experimental trial. Pre- and posttesting included measures of physical performance (20-m sprint, step-in vertical jump, agility, sit and reach, line drill, and Yo-Yo intermittent recovery level 1), strength (15 s push-up and pull-up), and functional movement screening (FMS). Both SG and VG achieved 3-5% ± 2-4% (mean ± 90% confidence limits) greater improvements in several physical performance measures (vertical jump height, 20-m sprint time, and Yo-Yo endurance performance) and a 28 ± 21% greater improvement in push-up strength compared with the CG. The SG attained substantially larger gains in FMS scores over both the VG (12 ± 10%) and CG (13 ± 8%). Video-based training appears to be a viable option to improve physical performance and strength in junior basketball athletes. Qualified supervision is recommended to improve functional movement patterns in junior athletes.

Purpose: To determine the effects of 10 wk of resistance or aerobic exercise training on interleukin-6 (IL-6) and C-reactive protein (CRP). Further, to determine pretraining and posttraining associations between alterations of IL-6 and CRP and alterations of total body fat mass (TB-FM), intra-abdominal fat mass (IA-FM), and total body lean mass (TB-LM)., Methods: A sample of 102 sedentary subjects were assigned to a resistance group (n = 35), an aerobic group (n = 41), or a control group (n = 26). Before and after intervention, subjects were involved in dual-energy x-ray absorptiometry, muscular strength and aerobic fitness, measurements and further provided a resting fasted venous blood sample for measures of IL-6, CRP, cholesterol profile, triglycerides, glucose, insulin, and glycosylated hemoglobin. The resistance and the aerobic groups completed a respective 10-wk supervised and periodized training program, whereas the control group maintained sedentary lifestyle and dietary patterns., Results: Both exercise training programs did not reduce IL-6; however, the resistance and the aerobic groups reduced CRP by 32.8% (P < 0.05) and 16.1% (P = 0.06), respectively. At baseline, CRP was positively correlated with IL-6 (r = 0.35), (TB-FM) (r = 0.36), and IA-FM (r = 0.31) and was inversely correlated with aerobic fitness measures (all r values > or = -0.24). Compared with the resistance and the control groups, the aerobic group exhibited significant (P < 0.05) improvements in all aerobic fitness measures and significant reductions in IA-FM (7.4%) and body mass (1.1%). Compared with the aerobic and the control groups, the resistance group significantly (P < 0.05) improved TB-FM (3.7%) and upper (46.3%) and lower (56.6%) body strength., Conclusion: Despite no alteration in baseline IL-6 and significantly smaller reductions in measures of adipose tissue as compared with the aerobic training group, only resistance exercise training resulted in significant attenuation of CRP concentration.

The use of instability devices and exercises to train the core musculature is an essential feature of many training centres and programs. It was the intent of this position stand to provide recommendations regarding the role of instability in resistance training programs designed to train the core musculature. The core is defined as the axial skeleton and all soft tissues with a proximal attachment originating on the axial skeleton, regardless of whether the soft tissue terminates on the axial or appendicular skeleton. Core stability can be achieved with a combination of muscle activation and intra-abdominal pressure. Abdominal bracing has been shown to be more effective than abdominal hollowing in optimizing spinal stability. When similar exercises are performed, core and limb muscle activation are reported to be higher under unstable conditions than under stable conditions. However, core muscle activation that is similar to or higher than that achieved in unstable conditions can also be achieved with ground-based free-weight exercises, such as Olympic lifts, squats, and dead lifts. Since the addition of unstable bases to resistance exercises can decrease force, power, velocity, and range of motion, they are not recommended as the primary training mode for athletic conditioning. However, the high muscle activation with the use of lower loads associated with instability resistance training suggests they can play an important role within a periodized training schedule, in rehabilitation programs, and for nonathletic individuals who prefer not to use ground-based free weights to achieve musculoskeletal health benefits.

Training of the trunk or core muscles for enhanced health, rehabilitation, and athletic performance has received renewed emphasis. Instability resistance exercises have become a popular means of training the core and improving balance. Whether instability resistance training is as, more, or less effective than traditional ground-based resistance training is not fully resolved. The purpose of this review is to address the effectiveness of instability resistance training for athletic, nonathletic, and rehabilitation conditioning. The anatomical core is defined as the axial skeleton and all soft tissues with a proximal attachment on the axial skeleton. Spinal stability is an interaction of passive and active muscle and neural subsystems. Training programs must prepare athletes for a wide variety of postures and external forces, and should include exercises with a destabilizing component. While unstable devices have been shown to be effective in decreasing the incidence of low back pain and increasing the sensory efficiency of soft tissues, they are not recommended as the primary exercises for hypertrophy, absolute strength, or power, especially in trained athletes. For athletes, ground-based free-weight exercises with moderate levels of instability should form the foundation of exercises to train the core musculature. Instability resistance exercises can play an important role in periodization and rehabilitation, and as alternative exercises for the recreationally active individual with less interest or access to ground-based free-weight exercises. Based on the relatively high proportion of type I fibers, the core musculature might respond well to multiple sets with high repetitions (e.g., >15 per set); however, a particular sport may necessitate fewer repetitions.

Context: Resistance training while using an instability-training device is known to increase activation of stabilizing muscle groups while decreasing the force generated by the prime movers during isometric contractions., Purpose: To investigate differences in squat kinetics during dynamic resistance training in an increasingly unstable training environment., Methods: Fourteen active men participated in this study. In each testing session, each participant performed 3 repetitions of squats with a 10-repetition maximum (10-RM) resistance, 40% of their 10-RM resistance, and 20.45 kg. The 3 testing session consisted of standing on a stable floor, foam pads, or BOSU balls. All repetitions were recorded with an optical encoder to record barbell kinetics., Results: The transition from stable (floor) to very unstable (BOSU) resulted in high likelihoods (>75%) of clinically meaningful differences ranging from small to large (effect size [ES] 0.31-1.73) in factors relating to concentric kinetics, eccentric power, and squat depth, regardless of the resistance used for training. There were also likely differences at the heaviest resistance in peak concentric power (stable to foam: ES 2.06; foam to BOSU: ES 0.38), eccentric power (stable to foam: ES 1.88; foam to BOSU: ES 0.74), and squat depth (stable to foam: ES 0.50; foam to BOSU: ES 0.67)., Conclusions: Resistance training in an unstable environment at an intensity sufficient to elicit strength gains of the prime movers results in deleterious effects in concentric squat kinetics and squat technique. Such observations are particularly evident on very unstable platforms.

Athletes use water immersion strategies to recover from training and competition. This study investigated the acute effects of postexercise water immersion after resistance exercise. Eighteen elite and subelite male volleyball athletes participated in an intervention using a randomized cross-over design. On separate occasions after resistance exercise, subjects completed 1 of 4 15-minute interventions: control (CON), cold water immersion (CWI), contrast watertherapy (CWT), or hot water immersion (HWI). Significance was accepted at p # 0.05. Resistance exercise induced significant temporal changes (time effect) for inflammatory, anthropometric, perceptual, and performance measures. Serum creatine kinase was reduced (g = 0.02-0.30) after CWI (p = 0.007), CWT (p = 0.006), or HWI (p < 0.001) vs. CON, whereas it increased significantly (g = 0.50) after CWI vs. HWI. Contrast water therapy resulted in significantly higher (g = 0.56) interleukin-6 concentrations vs. HWI. Thigh girth increased (g = 0.06-0.16) after CWI vs. CON (p = 0.013) and HWI (p < 0.001) and between CWT vs. HWI (p = 0.050). Similarly, calf girth increased (g = 0.01-0.12) after CWI vs. CON (p = 0.039) and CWT (p = 0.018), and HWI vs. CON (p = 0.041) and CWT (p = 0.018). Subject belief in a postexercise intervention strategy was associated with HSP72 ("believer">"nonbeliever," p = 0.026), muscle soreness ("believer">"nonbeliever," p = 0.002), and interleukin-4 ("nonbeliever">"believer," p = 0.002). There were no significant treatment x time (interaction effect) pairwise comparisons. Choice of postexercise water immersion strategy (i.e., cold, contrast, or hot) combined with a belief in the efficacy of that strategy to enhance recovery or performance improves biological and perceptual markers of muscle damage and soreness. On same or subsequent days where resistance exercise bouts are performed, practitioners should consider athlete beliefs when prescribing postexercise water immersion, to reduce muscle soreness. [ABSTRACT FROM AUTHOR]

Purpose: Recovery from exercise-induced muscle damage (EIMD) is paramount in sports performance. Foam rolling (FR) has been suggested to improve acute performance; however, the ability to facilitate recovery from eccentric (ECC) exercise remains unclear. Methods: Eleven males undertook 6 × 25 ECC knee extensions to induce muscular damage. Immediately, 24, 48, and 72 h post-training countermovement jump (CMJ), maximal voluntary isometric contraction (MVIC), pressure-pain threshold (PPT), knee flexion range of motion (ROM), and mid-thigh circumference (MTC) were assessed. Neurophysiological measures included voluntary activation (VA), peak twitch torque (PTT), time to peak twitch (PTTtime), and rate of twitch torque development (RTD). Participants then spent 15 min FR prior to each time point or control (CON). Repeated measures analysis of variance (ANOVA) and standardized effect sizes (Hedges' g) ± 95% confidence intervals (95% CI) were used to compare FR and CON. Results: CMJ was greater for FR compared to CON (P = 0.030) at 72 h (8.6%, P = 0.004) with moderate effects observed at 48 and 72 h (g = 0.54–0.66). PPT was greater with FR (P = 0.018) at 48 h only (23.7%, P = 0.013), with moderate to large effects noted at all-time points (g = 0.55–0.98). No significant differences were reported for MVIC (P = 0.777, -5.1 to 4.2%), ROM (P = 0.432, 1.6–3.5%), VA (P = 0.050, 3.6–26.2%), PTT (P = 0.302, -3.9 to 9.9%), PTTtime (P = 0.702, -24.4 to 23.5%), RTD (P = 0.864, -16.0 to -1.0%), or MTC (P = 0.409, -0.5 to -0.1%) between conditions. Conclusion: FR appears to improve jump performance in the later stages of recovery following ECC exercise. This may be in part due to improved pain tolerance; however, mechanical and neurophysiological are not modulated with FR. [ABSTRACT FROM AUTHOR]

The article reports on research which was conducted to investigate the effectiveness of Olympic style weightlifting (OWL), plyometric and traditional resistance training in children. Researchers evaluated 63 children who were assigned to one of the three training programs. They concluded that any of the three training methods could be implemented with children to enhance training adaptations.

Some research suggests that strength improvements are greater when resistance training continues to the point at which the individual cannot perform additional repetitions (i.e., repetition failure). Performing additional forced repetitions after the point of repetition failure and thus further increasing the set volume is a common resistance training practice. However, whether short-term use of this practice increases the magnitude of strength development with resistance training is unknown and was investigated here. Twelve basketball and 10 volleyball players trained 3 sessions per week for 6 weeks, completing either 4 X 6, 8 X 3, or 12 X 3 (sets X repetitions) of bench press per training session. Compared with the 8 X 3 group, the 4 X 6 protocol involved a longer work interval and the 12 X 3 protocol involved higher training volume, so each group was purposefully designed to elicit a different number of forced repetitions per training session. Subjects were tested on 3- and 6-repetition maximum (RM) bench press (81.5 ± 9.8 and 75.9 ± 9.0 kg, respectively, mean ± SD), and 40-kg Smith Machine bench press throw power (589 ± 100 W). The 4 X 6 and 12 X 3 groups had more forced repetitions per session (p > 0.01) than did the 8 X 3 group (4.1 ± 2.6, 3.1 ± 3.5, and 1.2 ± 1.8 repetitions, respectively), whereas the 12 X 3 group performed approximately 40% greater work and had 30% greater concentric time. As expected, all groups improved 3RM (4.5 kg, 95% confidence limits, 3.1-6.0), 6RM (4.7 kg, 3.1-6.3), bench press throw peak power (57 W, 22-92), and mean power (23 W, 4-42) (all p ≤ 0.02). There were no significant differences in strength or power gains between groups. In conclusion, when repetition failure was reached, neither additional forced repetitions nor additional set volume further improved the magnitude of strength gains. This finding questions the efficacy of adding additional volume by use of forced repetitions in young athletes with moderate strength training experience. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Following resistance training the acute effects of cold water immersion (CWI), contrast water therapy (CWT) and hot water immersion (HWI) on performance and perceived muscle soreness are not well characterised. This study assessed the effects of an acute bout of hydrotherapy compared with passive seated rest for 15 min (CON) on recovery (<48h) after a single, whole-body resistance training session. METHODS: Male sub-elite volleyball players (n=19, 24.1±5.5y, 181.9±8.9m, 78.4±11.2kg) were assessed for perceived muscle soreness (DOMS) and countermovement jumps (CMJ) performance prior to and immediately following a resistance training session. Athletes completed one of four 15min hydrotherapy strategies (CWI: 15°C; CWT: 7x2min, alternating hot 38°C and cold; HWI: 38°C), in a randomised order with at least 96h between trials with DOMS and CMJ reassessed immediately (0), 2, 24 and 48h post-resistance training. Flight time to contraction time (FT:CT) and a modified Reactive Strength Index (RSImod) were calculated from each CMJ. Data are presented as mean percent (%) change x/÷ 90% confidence intervals (CI) factor with the magnitude interpreted using effect size (ES, partial eta squared) and a linear mixed model was used to analyse the main and interaction effects. RESULTS: Immediately post-intervention RSImod and FT:CT increased compared to baseline (<8.1% x/÷ 0.02, p=0.02, ES=0.35-0.46) in CON and small effects were observed for CWI and CWT (<7.7% x/÷ 0.06, ES=0.37-0.53). Performance decreased 2h post exercise in CWT and HWI conditions (-5% x/÷ 0.05, ES=0.20). During CON RSImod and FT:CT (8x/÷ 0.02, ES=0.31-0.36) were increased at 48h while other conditions returned to baseline. Large correlations were observed between FT:CT and RSImod across all time points (r=0.77-0.94); however, greater main effects were observed in FT:CT. No significant intervention x group interaction for FT:CT and RSImod was observed. DOMS increased in all conditions at 24 and 48h (p<0.03, ES=0.80-1.61) with the large effects observed in CWT and HWI (ES=1.40-1.61). DISCUSSION: Hydrotherapy does not appear to influence CMJ performance following a resistance training bout, but may substantially effect the perception of recovery. Although a large correlation was observed between jumping variables across time, an increased number of effects were observed for FT:CT. Suggesting, that in a semi-elite male habituated jumping cohort, FT:CT has a greater sensitivity to fatigue post-resistance training than RSImod. PRACTICAL APPLICATIONS: When monitoring neuromuscular fatigue using CMJ, FT:CT may provide a more sensitive measure. CON may be more effective for recovery post-resistance training at 48h than CWI, CWT and HWI on jumping performance. HWI and CWT may have detrimental effects on jump performance 2h post resistance-training and therefore, should be used with caution if prescribed as an intervention between successive training sessions performed on the same day. [ABSTRACT FROM AUTHOR]

Purpose: The objective of this study is to understand the effectiveness of foam rolling (FR) as a recovery tool after exercise-induced muscle damage, analyzing thigh girth, muscle soreness, range of motion (ROM), evoked and voluntary contractile properties, vertical jump, perceived pain while FR, and force placed on the foam roller. Methods: Twenty male subjects (≥3 yr of strength training experience) were randomly assigned into the control (n = 10) or FR (n = 10) group. All the subjects followed the same testing protocol. The subjects participated in five testing sessions: 1) orientation and one-repetition maximum back squat, 2) pretest measurements, 10 x 10 squat protocol, and POST-0 (posttest 0) measurements, along with measurements at 3) POST-24, 4) POST-48, and 5) POST-72. The only between-group difference was that the FR group performed a 20-min FR exercise protocol at the end of each testing session (POST-0, POST-24, and POST-48). Results: FR substantially reduced muscle soreness at all time points while substantially improving ROM. FR negatively affected evoked contractile properties with the exception of half relaxation time and electromechanical delay (EMD), with FR substantially improving EMD. Voluntary contractile properties showed no substantial between-group differences for all measurements besides voluntary muscle activation and vertical jump, with FR substantially improving muscle activation at all time points and vertical jump at POST-48. When performing the five FR exercises, measurements of the subjects' force placed on the foam roller and perceived pain while FR ranged between 26 and 46 kg (32%-55% body weight) and 2.5 and 7.5 points, respectively. Conclusion: The most important findings of the present study were that FR was beneficial in attenuating muscle soreness while improving vertical jump height, muscle activation, and passive and dynamic ROM in comparison with control. FR negatively affected several evoked contractile properties of the muscle, except for half relaxation time and EMD, indicating that FR benefits are primarily accrued through neural responses and connective tissue. [ABSTRACT FROM AUTHOR]