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Purpose: This study analyzed the acute mechanical response to three workouts of the day (WOD) protocols in as many repetitions as possible (AMRAP), every minute on the minute (EMOM), and for time (FT) models by quantifying the degree of mechanical fatigue induced by popular resistance exercises in the Cross modalities, front squat (FS), and shoulder press (SP). We also analyzed whether the exercises' fastest velocity (Vfastest) could be an objective indicator of relative intensity (%1RM). Methods: Nine trained men performed three FS and SP exercises protocols. The degree of fatigue was quantified by the velocity loss (VL) achieved in both exercises and the velocity loss achieved in the WOD (VLWOD). Results: The VLWOD in the AMRAP, EMOM, and FT protocols was 73.2 ± 10.9%, 61.6 ± 15.1%, and 76.1 ± 8.8%, respectively. In the AMRAP and FT protocol, the Vfastest showed very strong relationships with the %1RM for FS and SP (r = -0.83, -0.75, respectively, p < .01); while in the EMOM protocol, there was a strong relationship between these variables, only for the SP (r = -0.61, p < .05). In the FT protocol, we observed an extremely strong relationship for FS (r = -0.91, p < .001) and very strong (r = -0.71, p < .05) for SP between these variables. Conclusion: Therefore, the AMRAP and FT training models induce the highest degrees of mechanical fatigue in the FS and SP exercises, and the Vfastest is a reliable tool for estimating relative intensity in resistance exercises of Cross modalities. [ABSTRACT FROM AUTHOR]

Da Silva-Grigoletto, ME, Fernandez, JM, de Sa, CA, Gomez-Puerto, JR, Vaamonde, D, and Perez-Jimenez, F. Fructose addition to a glucose supplement modifies perceived exertion during strength and endurance exercise. J Strength Cond Res 24(12): 3334-3342, 2010-The addition of fructose (F) to a glucose (G) supplement may modify the metabolic response during exercise; however, its effect on perceived exertion (PE) and its influence on postprandial metabolism have not been jointly studied in different types of exercise. This study sought to assess the acute effects of F addition to a G supplement on PE and on the postprandial metabolic response during a single bout of either strength exercise (SE) or endurance exercise (EE). Twenty physically trained men ingested an oral dose of G or GF 15 minutes before starting a 30-minute session of SE (10 sets of 10 repetitions of half squat) or EE (cycling). The combination resulted in 4 randomized interventions in a crossover design in which all subjects performed all experimental conditions: G + SE, GF + SE, G + EE, and GF + SE. Perceived exertion, heart rate (HR), G, insulin, lactate, and urinary catecholamine levels were measured before exercise, during the exercise, and during acute recovery. Perceived exertion during exercise was lower for GF than for G during SE and EE (mean [+ or -] SD; 8.95 [+ or -] 0.62 vs. 9.26 [+ or -] 0.65, p < 0.05 and 7.47 [+ or -] 0.84 vs. 7.74 [+ or -] 0.93, p < 0.05, respectively). The glycemic peak in GF + SE was lower than in G + SE (p < 0.05), and there was a second peak during recovery (p < 0.05), whereas in EE, no difference in blood G levels was noted between G and GF supplements. Moreover, HR, urinary adrenalin, and noradrenalin were lower in GF than in G (p < 0.05), though only for EE. The results showed that PE is positively affected by GF supplementation for both SE and EE and thus may be a useful dietary strategy for helping to achieve higher training loads. KEY WORDS RPE, fructose metabolism, heart rate, catecholamine

The acute ingestion of a supplement with different glycemic carbohydrates, including fructose, is a typical practice for athletes before exercising. Observational evidence suggests that different metabolic responses may modify the exercise-stimulated endothelium-dependent vasodilation. The purpose of the present study was to investigate whether endothelial reactivity, stimulated by anaerobic exercise (AnE) or aerobic exercise (AE), both performed with glycemic supplementation, is modified by the addition of fructose. Twenty physically trained men ingested an oral dose of glucose (G) or glucose plus fructose (F) 15 minutes before starting a 30-minute session of AnE (10 sets of 10 repetitions of half squat) or AE (cycling). The combination resulted in 4 randomized interventions in a crossover design in which all subjects performed all experimental conditions: G + AnE, F + AnE, G + AE, and F + AE. Ischemic reactive hyperemia (IRH), glycemia, plasma lipoperoxides (LPOs), nitric oxide (NO), and lactate were determined at baseline, exercise, and acute recovery time points. Immediately after AnE, IRH was 26.35% higher in F + AnE than in G + AnE (p < 0.05); this difference rose to 27.24% at the end of the recovery period (p < 0.05). The glycemic peak in F + AnE was lower than in G + AnE (p < 0.05), and there was a second peak during recovery (p < 0.05). There were no differences observed in LPO between anaerobic trials, but the NO bioavailability increased and was higher in F + AnE than in G + AnE after exercise and recovery (p < 0.05). Residual lactate was also higher under the F + AnE condition (p < 0.05). During AE, there were no differences in IRH, glycemia, or NO between groups, but LPO was significantly higher after F supplementation. These results suggest that the addition of fructose to a single G supplement ingested before a glycolitic exercise can modify the glucoregulation and increases ischemic reactive hyperemia. KEY WORDS fructose, glycemic index, glycemic response, endothelial function

This experiment was designed to assess the acute (Study I) and cumulative response (Study II) of muscle performance to differing recovery times after exposure to whole body vibration (WBV). All subjects (mean age 19.7 [+ or -] 1.9) were healthy and physically active. In both studies, subjects were exposed to a WBV bout of 6 exposures of 60 seconds each, with frequency of 30 Hz and amplitude of 4 mm. In Study I, subjects (n = 30) underwent 3 trials (1 per day) on different days with a 2-day wash-out period between trials; each trial included either a 1, 2, or 3 minutes of recovery between exposures to WBV. All subjects underwent all trials, which were randomly assigned. Jump ability and muscle power were measured before and after each bout. In Study II, subjects (n = 45) underwent 12 sessions of WBV training in 4 weeks (3 bouts/ wk). The subjects were randomly assigned to 1 of the following 3 groups: WBV with 1-minute recovery periods between exposures, WBV with 2-minute recovery periods between exposures, or control group. Jump ability, muscle power, and strength were measured before and after each bout. In the acute study (I), recovery times of 1 and 2 minutes enhanced all measured parameters (p < 0.05), with the 2-minute recovery being more effective. In the long-term study (11), however, although both periods also enhanced the measured parameters (p < 0.05), the 1-minute recovery proved more effective because the response was modified by systematic stimulation. In conclusion, 2-minute recovery periods provided the most effective acute enhancement of muscle activation, whereas the 1-minute recovery provided a more effective cumulative enhancement of muscle power and jump ability. KEY WORDS training, muscular strength, muscular power

A training program designed to increase strength and aerobic endurance in 1 season was tested on 16 professional soccer players from Spain with a mean age of 28 [+ or -] 3.37 years. The schedule comprised 4 macrocycles of 12 weeks of aerobic endurance and strength training. As much for the strength training as for the aerobic endurance, the program used a sequence of general, special, and specific exercises. Assessments were made with routine tests (i.e., squat jumps [SJs], countermovement jumps [CMJs], and countermovement jumps with arm swing [CMJas]) at the end of each macrocycle, and the Probst test was used to assess aerobic endurance as a function of running speed and distance, at the start and end of the training schedule and at the start of the third macrocycle. Jumps were performed on an infrared platform fitted to the MuscleLab system. The Probst test showed differences between the first evaluation and the second and third evaluations: 3,550 [+ or -] 411.59 m vs. 2,006 [+ or -] 207.20 m (P < 0.01). For 2 of the 3 jumps analyzed, the results were better in the last 2 than in the first 2 evaluations (SJ, 43.13 [+ or -] 3.77 vs. 39.47 [+ or -] 3.4 [P < 0.05]; CMJ, 49.80 [+ or -] 3.77 vs. 46.67 [+ or -] 3.76 [P < 0.05]; CMJas, 56.24 [+ or -] 5.2 vs. 52.98 + 4.54 [P > 0.05]). Improvement of aerobic endurance was produced on the first phase of the season as a consequence of the training. To increase strength, it is necessary to augment the number of training sessions of this type. It is convenient to separate aerobic endurance and strength training to create more ample blocks during the last 2 macrocycles. KEY WORDS training, adaptation, macrocycles, strength; aerobic endurance

Current literature shows studies that question the safety of the practices carried out in high-intensity training modalities such as CrossFit®, Cross Training or High-Intensity Functional Training, which may lead to a greater risk in the prevalence of injuries. The aim of this study was to analyze in detail the prevalence of injuries occurring in training based on the CrossFit®, Cross Training or High-Intensity Functional Training modalities, through a systematic review, as well as evaluating the methodological quality of the included studies. We used the recommendations of the PRISMA protocol. For the quality analysis of the studies, we applied the tool proposed by the National Institute of Health (United States). The areas that mainly present a higher risk of injury during CrossFit, Cross Training or High-Intensity Functional Training practices are shoulders, knees and back. Additionally, 11 of the 12 included studies displayed a poor methodological quality according to the quality tool used. [ABSTRACT FROM AUTHOR]

The objective was to investigate the effects of functional (FT) and traditional (TT) training on trunk muscles maximal isometric strength, rate of force development and endurance with trained elderly women. Forty-five elderly women were directed into three groups: FT (n =1 6), TT (n = 14) and Control (n = 15). The FT (multi-planar, and multi-articular movements) and TT (primarily machine-based resistance exercises) performed mobility, muscle strength and power exercises. Both training groups also performed intermittent cardiometabolic activities. The maximum strength and endurance of the trunk muscles were verified, both at baseline and after 12 weeks of training (3xweek for 50 min each). Data were analyzed using a 2-way ANCOVA with contrast of adjusted mean values. FT significantly increased all variables: maximum trunk flexor strength (p = 0.002, 22%); rate of flexor force development (p = 0.001, 84%); trunk extensors maximal strength (p = 0.003, 17%); trunk extensor rate of force development (p = 0.05, 16%); trunk flexors (p = 0.001, 19%) and extensors (p = 0.017, 13%) endurance compared to baseline. TT showed an increase only in RFD of trunk extensors (p = 0.003, 53%), and flexors (p = 0.033, 42%), and trunk flexors endurance (p = 0.008, 11%). However, there was no statistically significant difference between groups. FT promoted improvement in all variables; strength, endurance and rate of force development of the trunk flexors and extensors of the elderly. On the other hand, TT improved only the rate of force development of trunk flexors and extensors and endurance of the trunk flexors. FT is recommended for elderly women as it improves a broader array of physiological parameters. [ABSTRACT FROM AUTHOR]

Introduction: Aging involves a progressive reduction of respiratory muscle strength as well as muscle strength. Purpose: Compare the effects of resistance training volume on the maximum inspiratory pressure (MIP), maximum expiratory pressure (MEP), functional performance, and muscle strength in elderly women. Methods: Thirty elderly women were randomly assigned to a group performing either single sets (1-SET) or three sets (3-SET) of exercises. The sit-to-stand test, MIP, MEP, and muscle strength were assessed before and after 24 training sessions. Progressive resistance training was performed two times per week for a total of 8-12 repetitions, using the main muscle groups of the upper and lower limbs. Results: The main results showed that the participants significantly increased their MEP (P,0.05; 1-SET: 34.6%; 3-SET: 35.8%) and MIP (P,0.05; 1-SET: 13.7%; 3-SET: 11.2%). Both groups also improved in the sit-to-stand test (P,0.05; 1-SET: 10.6%; 3-SET: 17.1%). After 24 training sessions, muscle strength also significantly increased (P,0.0001; 40%-80%) in both groups. An intergroup comparison did not show any statistically significant differences between the groups in any of the parameters analyzed. Conclusion: Single- and multiple-set resistance training programs increased MIP, MEP, muscle strength, and sit-to-stand test performance in elderly women after 24 sessions of training. In conclusion, our results suggested that elderly women who are not in the habit of physical activity may start with single-set resistance training programs as a short-term strategy for the maintenance of health. [ABSTRACT FROM AUTHOR]

Current literature shows studies that question the safety of the practices carried out in high-intensity training modalities such as CrossFit®, Cross Training or High-Intensity Functional Training, which may lead to a greater risk in the prevalence of injuries. The aim of this study was to analyze in detail the prevalence of injuries occurring in training based on the CrossFit®, Cross Training or High-Intensity Functional Training modalities, through a systematic review, as well as evaluating the methodological quality of the included studies. We used the recommendations of the PRISMA protocol. For the quality analysis of the studies, we applied the tool proposed by the National Institute of Health (United States). The areas that mainly present a higher risk of injury during CrossFit, Cross Training or High-Intensity Functional Training practices are shoulders, knees and back. Additionally, 11 of the 12 included studies displayed a poor methodological quality according to the quality tool used., (© 2020 Yaira Barranco-Ruiz, Emilio Villa-González, Antonio Martínez-Amat, Marzo E. Da Silva-Grigoletto, published by Sciendo.)

Aim: This study compared the effect of different resistance training (RT) frequencies on total, android, gynoid and trunk body fat in overweight/obese older women., Methods: Fifty-seven overweight/obese older women (66.9±5.3 years and 39.9±4.9% body fat) were randomly assigned to one of three groups: a group performing RT twice a week (G2X), a group performing RT three times a week (G3X), or a non-exercise control group (CG). Both training groups performed the same 12-week RT program consisting of 8 exercises that trained all major muscle groups. Dual-energy X-ray absorptiometry was used to assess body composition., Results: After the intervention period, both G2X and G3X demonstrated significant (P<0.05) reductions in adiposity compared to the CG for total body fat (G2X=-1.7%, G3X=-2.7%, CG=+2.1%), android fat (G2X=-6.2%, G3X=-7.0%, CG=+8.6%), gynoid fat (G2X=-2.5%, G3X=-2.9%, CG=+1.0%), and trunk fat (G2X=-2.5%, G3X=-3.0%, CG=+2.9%), with no significant differences between training groups., Conclusion: These results demonstrate that a low-volume 12-week RT program performed two or three times per week causes decreases in total and regional fat deposition with the greatest reductions occurring in the android region., Competing Interests: The authors declare no conflict of interest., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: The aim of this paper was to analyze how the rest between interval repetitions in intra-set training (at maximal isometric loads) could affect the ability to repeat maximal contractions in subjects with different levels of performance and different experience in strength development work., Methods: Twenty subjects were divided randomly into two different groups depending on their sport characteristics: ten subjects were trained in strength development work (Group Strenght--23.1±4.6 years; 172.0±5.3 cm; 79.9±12.1 kg; 2175.6±490.8 N; 46.9±4.9 mL/kg.min), and ten subjects were trained in endurance work (Group Endurance--21.3±4.5 years; 172.4±4.1 cm; 60.0±4.6 kg; 815.5±206.5 N; 67.4±4.9 mL/kg.min). To assess the ability to repeat maximal efforts, 20 repetitions of 5 seconds were performed in a half-squat position, with 1 minute of rest between repetitions., Results: For both groups, four different phases were observed in the Interval Maximal Force test during the 20-repetition assessment: potentiation, maintenance, moderate loss, and significant loss. For the GE, the loss in maximum strength capacity began in the fourth repetition (GS4th: 3.4%, ns, Effect Size: 0.09 vs. GE3th: 1.6%; ns; ES: 0.06) and reached a statistically significant value in the twelfth repetition (GS12th: 12.7%, P=0.03, ES: 0.35 vs. GE7th: 12.5%; P=0.01; ES: 0.49). The number of repetitions at which the strength began to decrease depended on the subject's sport characteristic and performance level., Conclusions: This study shows how an appropriate intra-set rest inclusion can significantly increase the work performed in every set without changing the muscle contraction characteristics, thus delaying muscle fatigue and maintaining the desired training objective.

The metabolic response when aerobic exercise is performed after the ingestion of glucose plus fructose is unclear. In the present study, we administered two beverages containing GluF (glucose+fructose) or Glu (glucose alone) in a randomized cross-over design to 20 healthy aerobically trained volunteers to compare the hormonal and lipid responses provoked during aerobic exercise and the recovery phase. After ingesting the beverages and a 15-min resting period, volunteers performed 30 min of moderate aerobic exercise. Urinary and blood samples were taken at baseline (t(-15)), during the exercise (t(0), t(15) and t(30)) and during the recovery phase (t(45), t(75) and t(105)). Plasma insulin concentrations were higher halfway through the exercise period and during acute recuperation (t(15) and t(75); P<0.05) following ingestion of GluF than after Glu alone, without any differences between the effects of either intervention on plasma glucose concentrations. Towards the end of the exercise period, urinary catecholamine concentrations were lower following GluF (t(45); P<0.05). Plasma triacylglycerol (triglyceride) concentrations were higher after the ingestion of GluF compared with Glu (t(15), t(30), t(45) and t(105); P<0.05). Furthermore, with GluF, we observed higher levels of lipoperoxides (t(15), t(30), t(45) and t(105); P<0.05) and oxidized LDL (low-density lipoprotein; t(30); P<0.05) compared with after the ingestion of Glu alone. In conclusion, hormonal and lipid alterations are provoked during aerobic exercise and recovery by the addition of a dose of fructose to the pre-exercise ingestion of glucose.