Gustavo Ribeiro da Mota

TIME COURSE OF STRENGTH AND POWER RECOVERY AFTER RESISTANCE TRAINING WITH DIFFERENT MOVEMENT VELOCITIES

Ide, BN, Leme, TCF, Lopes, CR, Moreira, A, Dechechi, CJ, Sarraipa, MF, da Mota, GR, Brenzikofer, R, and Macedo, DV. Time course of strength and power recovery after resistance training with different movement velocities. J Strength Cond Res 25(7): 2025-2033, 2011—The purpose of this study was to evaluate the time course of strength and power recovery after a single bout of strength training designed with fast and slow contraction velocities. Nineteen male subjects were randomly divided into 2 groups: the slow-velocity contraction (SV) group and the fast velocity contraction (FV) group. Resistance training protocols consisted of 5 sets of 12 repetition maximum (5 × 12RM) with 50 seconds of rest between sets and 2 minutes between exercises. Contraction velocity was controlled by the execution time for each repetition (SV—6 seconds to complete concentric and eccentric phases and for FV—1.5 seconds). Leg Press 45° 1RM (LP 1RM), horizontal countermovement jump (HCMJ), and right thigh circumference (TC) were accessed in 6 distinct moments: base (1 week before exercise), 0 (immediately after exercises), 24, 48, 72, and 96 hours after exercise protocol. The SV and FV presented significant LP 1RM decrements at 0, and these were still evident 24-48 hours postexercise. The magnitude of decline was significantly (p < 0.05) higher for FV. The SV and FV presented significant HCMJ decrements at 0, but only for FV were these still evident 24-72 hours postexercise. The SV and FV presented significant TC increments at 0, and these were still evident 24-48 hours postexercise for SV but for FV it continued up to 96 hours. The magnitude of increase was significantly (p < 0.05) higher for FV. In conclusion, the fast contraction velocity protocol resulted in greater decreases in LP 1RM and HCMJ performance, when compared with slow velocity. The results lead us to interpret that this variable may exert direct influence on acute muscle strength and power generation capacity.

Low appendicular muscle mass is correlated with femoral neck bone mineral density loss in postmenopausal women

BackgroundAfter menopause, rapid bone mass loss occurs in response to hypoestrogenism. Several studies suggest that muscle mass and bone mineral density (BMD) are positively associated in postmenopausal women. Therefore, it may be assumed that postmenopausal low appendicular muscle mass (aMM) can increase BMD loss in a short period of time.ObjectiveThe purpose of this study was to assess relationship of aMM with femoral neck BMD in postmenopausal women.MethodsProspective, controlled clinical Trial including 64 women aged 45-70 years, who had not had their last menstruation for at least one year. Subjects were divided into two groups: low aMM (n = 32), and normal aMM (n-32). Femoral neck BMD and muscle mass were measured by DXA at baseline and after twelve months. Pairwise and independent t tests were used for data analysis.ResultsBaseline weight, BMI and muscle mass (total and appendicular) significantly differ between groups (p < 0.05). After twelve months, femoral neck BMD was significantly lower in the group with low aMM, whereas no significant difference was observed in the group with normal aMM (p < 0.05).ConclusionIn postmenopausal women, low appendicular muscle mass is associated negatively with femoral neck BMD in a short period of time.

MUSCLE MASS GAIN AFTER RESISTANCE TRAINING IS INVERSELY CORRELATED WITH TRUNK ADIPOSITY GAIN IN POSTMENOPAUSAL WOMEN

Abstract Orsatti, FL, Nahas, EAP, Orsatti, CL, de Oliveira, EP, Nahas-Neto, J, da Mota, GR, and Burini, RC. Muscle mass gain after resistance training is inversely correlated with trunk adiposity gain in postmenopausal women. J Strength Cond Res 26(8): 2130–2139, 2012—The aim of this study was to evaluate alterations in trunk adiposity (TA) over 9 months of resistance training (RT) and associate these changes with the hypertrophy of muscle mass (MM) in postmenopausal women (PW). The investigation used a sample that consisted of 22 PW (44–69 years old). The group was subjected to RT (60–80% of 1 repetition maximum) for the total body 3 d·wk−1. Body composition (dual-energy x-ray absorptiometry) and plasma levels of insulin-like growth factor-1 (IGF-1), follicle-stimulating hormone, E2 (Immulite system), and interleukin-6 (IL-6; enzyme-linked immunosorbent assay) were assessed at the beginning and end of the experiment. After RT, only women who acquired up to 5% TA gained MM, whereas women who acquired >5% TA exhibited increased IL-6 and no MM gain (p < 0.05). The &Dgr;MM was negatively associated with time of menopause (r = −0.45, p < 0.05) and positively associated with baseline IGF-1 (r = 0.47, p < 0.05). Only &Dgr;LE (leg extension) was negatively associated with baseline IL-6 (p < 0.05). Trunk adiposity growth (&Dgr;TF, kilograms) was positively correlated with changes in IL-6 (r = 0.68, p < 0.05). The MM gain was negatively correlated with &Dgr;TF (r = −0.63, p < 0.05) and changes in IL-6 (r = −0.73, p < 0.05). After adjusting all of the confounding variables, only baseline IGF-1 (positively) and changes in IL-6 (negatively) influenced MM, and only the increase in TA influenced IL-6. Our study suggests that increased levels of TA during RT increase IL-6 concentrations, which is a significant negative predictor of MM gain in PW.

Ischemic Preconditioning and Placebo Intervention Improves Resistance Exercise Performance

Abstract Marocolo, M, Willardson, JM, Marocolo, IC, da Mota, GR, Simão, R, and Maior, AS. Ischemic preconditioning and PLACEBO intervention improves resistance exercise performance. J Strength Cond Res 30(5): 1462–1469, 2016—This study evaluated the effect of ischemic preconditioning (IPC) on resistance exercise performance in the lower limbs. Thirteen men participated in a randomized crossover design that involved 3 separate sessions (IPC, PLACEBO, and control). A 12-repetition maximum (12RM) load for the leg extension exercise was assessed through test and retest sessions before the first experimental session. The IPC session consisted of 4 cycles of 5 minutes of occlusion at 220 mm Hg of pressure alternated with 5 minutes of reperfusion at 0 mm Hg for a total of 40 minutes. The PLACEBO session consisted of 4 cycles of 5 minutes of cuff administration at 20 mm Hg of pressure alternated with 5 minutes of pseudo-reperfusion at 0 mm Hg for a total of 40 minutes. The occlusion and reperfusion phases were conducted alternately between the thighs, with subjects remaining seated. No ischemic pressure was applied during the control (CON) session and subjects sat passively for 40 minutes. Eight minutes after IPC, PLACEBO, or CON, subjects performed 3 repetition maximum sets of the leg extension (2-minute rest between sets) with the predetermined 12RM load. Four minutes after the third set for each condition, blood lactate was assessed. The results showed that for the first set, the number of repetitions significantly increased for both the IPC (13.08 ± 2.11; p = 0.0036) and PLACEBO (13.15 ± 0.88; p = 0.0016) conditions, but not for the CON (11.88 ± 1.07; p > 0.99) condition. In addition, the IPC and PLACEBO conditions resulted insignificantly greater repetitions vs. the CON condition on the first set (p = 0.015; p = 0.007) and second set (p = 0.011; p = 0.019), but not on the third set (p = 0.68; p > 0.99). No difference (p = 0.465) was found in the fatigue index and lactate concentration between conditions. These results indicate that IPC and PLACEBO IPC may have small beneficial effects on repetition performance over a CON condition. Owing to potential for greater discomfort associated with the IPC condition, it is suggested that ischemic preconditioning might be practiced gradually to assess tolerance and potential enhancements to exercise performance.

The effects of ball possession status on physical and technical indicators during the 2014 FIFA World Cup Finals.

ABSTRACT This study examined the effect of high- (HPBPT) and low-percentage ball possession (LPBPT) on physical and technical indicators during 2014 FIFA World Cup matches. This would enable a regression model to be constructed to further understand the impact of different ball possession (BP) strategies on match performance. Data were collected from 346 international soccer players using a multiple-camera computerised tracking system. Although players in HPBPT covered lower distances (P < 0.01) in total and at low speed compared to LPBPT, this produced a trivial effect size (ES). However, they covered similar distances (P > 0.05) at medium and high speeds. Players in LPBPT covered more distance without BP but less with BP than HPBPT (P < 0.01; ES large). All positions in LPBPT spent less time in the opposing half and attacking third than the players in HPBPT (P < 0.01; ES small–moderate), but all positions in HPBPT completed more short and medium passes than LPBPT (P < 0.01; ES moderate). Players in HPBPT produced more solo runs into the attacking third and penalty area than LPBPT (P < 0.05, ES small). The equation to predict BP from physical and technical indicators highlighted the importance of distances covered (total, with and without BP), time spent in the attacking third and successful short passes during matches. In practical terms, high or low BP does not influence the activity patterns of international matches although HPBPT spend more time in offensive areas of the pitch.

MUSCLE DAMAGE OF RESISTANCE-TRAINED MEN AFTER TWO BOUTS OF ECCENTRIC BENCH PRESS EXERCISE

Abstract Meneghel, AJ, Verlengia, R, Crisp, AH, Aoki, MS, Nosaka, K, da Mota, GR, and Lopes, CR. Muscle damage of resistance-trained men after two bouts of eccentric bench press exercise. J Strength Cond Res 28(10): 2961–2966, 2014—The present study tested the hypothesis that resistance-trained individuals would also show less muscle damage in the second than in the first eccentric exercise bout (i.e., repeated bout effect) as shown in untrained individuals. This study investigated changes in indirect markers of muscle damage after 2 bouts of free weight eccentric exercise performed by 8 resistance-trained men. The participants (24.4 ± 1.2 years) performed 4 sets of 8 eccentric actions (3 seconds for each repetition) at 70% of eccentric 1 repetition maximum (1RM) load in a bench press exercise with 2 minutes of rest between sets, and repeated the same exercise 2 weeks later. Bench press 1RM, delayed onset muscle soreness (DOMS) assessed by a 6-point Likert scale, serum creatine kinase (CK) activity, and plasma prostaglandin E2 concentration (PGE2) were measured before and 24, 48, 72, and 96 hours after the exercise, and the changes were compared between bouts. The changes in the variables were smaller (p ⩽ 0.05) after the second than the first bout indicated by a smaller decline in 1RM strength (first bout: −10.2 ± 1.0% vs. second bout: −5.7 ± 1.5%), peak DOMS (3.8 ± 0.4 vs. 1.7 ± 0.5), peak CK (637.3 ± 133.3 vs. 305.4 ± 63.6 IU·L−1), and peak PGE2 (761.2 ± 171.0 vs. 307.2 ± 48.3 pg·mL−1). These results show a typical repeated bout effect. Thus, it is concluded that the repeated bout effect occurs in resistance-trained individuals.

Optimal load for the peak power and maximal strength of the upper body in Brazilian Jiu-Jitsu athletes.

Abstract da Silva, BVC, de Moura Simim, MA, Marocolo, M, Franchini, E, and da Mota, GR. Optimal load for the peak power and maximal strength of the upper body in Brazilian Jiu-Jitsu athletes. J Strength Cond Res 29(6): 1616–1621, 2015—We determined the optimal load for the peak power output (PPO) during the bench press throw (BPT) in Brazilian Jiu-Jitsu (BJJ) athletes and compared the PPO and maximal strength between advanced (AD) and nonadvanced (NA) athletes. Twenty-eight BJJ athletes (24.8 ± 5.7 years) performed the BPT at loads of 30, 40, 50, and 60% of their 1 repetition maximum (RM) in a randomized order (5-minute rest between BPTs). The PPO was determined by measuring the barbell displacement by an accelerometer (Myotest). The absolute (F = 7.25; p < 0.001; effect size [ES] = 0.21) and relative intensities were different (F = 7.11; p < 0.001; ES = 0.21) between the AD and NA. There was also a group and intensity interaction effect (F = 2.79; p = 0.046; ES = 0.10), but the differences were centered around the AD group, which achieved higher values using 40% (p = 0.001) and 50% of the 1RM (p < 0.001) than the PPO with 60% of 1RM. The AD athletes presented with higher 1RM than NA (p ⩽ 0.05; ES = 1.0), but there was no difference (p > 0.05) in the PPO (30–60% 1RM). A polynomial adjustment indicated that the optimal load was ∼42% of 1RM for all groups and subgroups (R 2 from 0.82 to 0.99). Our results suggest that there can be (1RM) differences between AD and NA BJJ athletes; however, there is no difference in the muscle power between the AD and NA groups. Additionally, ∼42% of 1RM seems to be the optimal load for developing maximal power using the BPT for the BJJ athletes.

Neuromuscular responses to simulated brazilian jiu-jitsu fights.

Abstract The aim of this study was to investigate the neuromuscular performance responses following successive Brazilian Jiu-Jitsu (BJJ) fights. Twenty-three BJJ athletes (age: 26.3 ± 6.3 years; body mass: 79.4 ± 9.7 kg; body height: 1.80 ± 0.1 m) undertook 3 simulated BJJ fights (10 min duration each separated by 15 min of rest). Neuromuscular performance was measured by the bench press throw (BPT) and vertical counter movement jump (VCMJ) tests, assessed before the 1st fight (Pre) and after the last one (Post). Blood lactate (LA) was measured at Pre, 1 min Post, and 15 min Post fights. Paired t-tests were employed in order to compare the BPT and VCMJ results. One-way ANOVA with Bonferroni post hoc tests were utilized to compare LA responses. The results revealed a significant (p < 0.05) increase in VCMJ performance (40.8 ± 5.5 cm Pre vs. 42.0 ± 5.8 cm Post), but no significant changes in the BPT (814 ± 167 W Pre vs. 835 ± 213 W Post) were observed. LA concentration increased significantly (p < 0.05) at Post, both in the 1st min and the 15th min of recovery. We concluded that successive simulated BJJ fights demanded considerable anaerobic contribution of ATP supply, reinforcing the high-intensity intermittent nature of the sport. Nevertheless, no negative impact on acute neuromuscular performance (power) was observed.

The Effects of Ischemic Preconditioning on Human Exercise Performance: A Counterpoint

Contrary to assertions made by many researchers, ischemic preconditioning (IPC) was not developed in the 1980s but instead had been tested in some manner since the 1950s, with controversial results [1–4]. The recent review published by Incognito et al. [5] presented important insights into IPC and exercise performance. The authors stated that it was necessary to investigate individual phenotypes because of the high heterogeneity of their results. They suggested that IPC could affect some subjects but not others, and classified them as IPC responders and nonresponders. Although their idea is interesting and well grounded [6], we would like to provide additional information regarding IPC and a counterpoint to their findings. First, the authors concluded that IPC can be an interesting ergogenic aid because of the 21 investigations they evaluated, ten showed some significant (p \ 0.05) exercise performance benefits of IPC, such as improved time-trial performance, increased maximal/peak oxygen uptake (VO2max/VO2peak), increased power output, or reduced selfreported perceived exertion ratings. However, upon further review of these studies, of the ten studies the authors mentioned as beneficial, five (50 %) did not have a placebo control group [7–11]. Although the authors acknowledged the potential influence of the placebo effect (as per the final paragraph of their discussion: ‘‘Further, a major confounder with all human studies remains the inability to effectively sham-control IPC treatments. Highlighting the potential influence of placebo effects on results...’’), only five studies [12–16] (24 % of the total) of the 21 selected studies in their review measured beneficial effects of IPC on athletic performance (or associated variables) when a placebo control group was present. The other 16 studies (76 % of the total) either did not have a placebo control group (nine studies) or did use a placebo control group (seven studies) but did not describe any improvement in exercise performance with IPC in comparison with placebo. Another point of interest was the absence of figures on the number of responders and non-responders in those studies in which conventional statistics (i.e. mean ± standard deviation) showed significantly detrimental effects (p\0.05) of IPC. For instance, Paixão et al. [17] tested 15 subjects. Eleven (73 %) had worse outcomes in comparison with placebo when the Wingate test was preceded by IPC. The other two studies were not mentioned at all. This may have been because of limitations in the authors’ literature search criteria. One placebo-controlled study showed no acute impact of IPC on specific aspects of shortterm neuromuscular function—such as resistance exercises, sprints, and squat jumps—but noted some beneficial effects of IPC 24 hours after use [18]. Finally, another study concluded that following strenuous eccentric exercise, IPC was unable to accelerate muscle recovery (24, 48, and 72 h later; there was no evaluation immediately after IPC) [19]. It is therefore reasonable to think that the numbers of responders and non-responders could be substantially different if the negative or equivocal studies were re-evaluated. Since the placebo effect can influence general human sport and exercise performance [20], it is critical to & Gustavo Ribeiro da Mota grmotta@gmail.com

Anthropometric profile and physical performance characteristic of the Brazilian amputee football (soccer) team

Amputee football is a variation of conventional soccer in which athletes with lower limb amputation and one athelete with upper limb amputation (the goalkeeper) participate. The objective of this study was to investigate the anthropometric and physical characteristics of amputee football athletes and to verify differences between heart rate peak (HRpeak) and equations for predicting maximum heart rate (HRmax). Twelve amputee soccer players from the Brazilian team participated in this study. The body mass, height and body composition were measured. The physical tests used were: the 20 m running test, the T-square test and the Yo Yo intermitent recovery test - level 1 (YYIRT1). The percentage of fat was significantly different between midfielders and defenders. No significant differences were found between positions in the physical tests. The HRpeak was significantly lower than all of HRmax prediction equations tested. We conclude that the indicators of physical performance did not differ significantly between the different tactics roles of players, and that, after intermittent maximum effort, the cardiac response was lower when compared with the investigated HRmax prediction equations.