Effects of myofascial release of the ankle plantar flexors on static postural balance of young men: A randomized clinical trial.

BACKGROUND: Myofascial release (MR) has been widely used in sports and clinical environment. There are studies that have already evaluated the effect of MR on postural control, however, the data found are inconclusive. OBJECTIVES: Investigate the effect of MR on ankle plantar flexor muscles over static postural balance. METHOD: Sixty-five young men were randomized allocated into one of three groups: 1) MR group (n = 25, Myofascial Release); 2) Sham (n = 25, fake intervention); or 3) Control group (n = 15). Both MR and Sham techniques were applied during 5 min in the ankle flexors of each leg. The bipodal static postural balance test was performed before and 2 min post each intervention on a force plate with eyes closed during the test. All subjects performed 3 sets of 30-s with 1 min of rest. Mean values to the center of pressure velocity (COPvel) was used for analysis. RESULTS: The bipodal balance test showed that there was no significant difference between groups (p > 0.05), but there was a significant time effect (p < 0.05). A significant decrease (p < 0.05) in post-test COPvel (cm.s-1) values (sham 4.9 ± 1.2; MR 4.5 ± 0.6; CON 4.22 ± 0.8) was found when compared to values of pre-test (sham 5.3 ± 1.0; MR 5.0 ± 0.8; CON 4.94 ± 1.3) for all groups. CONCLUSIONS: The results demonstrated that MR performed on ankle flexors did not affect static postural balance in young man. This study is a clinical trial (Register Number: RBR-48k5jm).

Acute effects of different rest intervals between agonist-antagonist paired-sets in the neuromuscular system performance of young adults.

INTRODUCTION: The agonist-antagonist paired-sets (APS) is a resistance training that involves alternating between exercises for agonist/antagonist muscles of a joint, with little or no rest between then. There is evidence that APS is more strenuous than traditional methods, but evidence on the optimal RI between agonist-antagonist actions is unknown. OBJECTIVE: The aim of this study was to compare different rest intervals between agonist-antagonist actions during APS in young adults. METHOD: Fifty healthy men (mean age 23.2 ± 2.8 years; 1.76 ± 0.1m height, 78.03 ± 8.1 kg) were included and performed three different agonist-antagonist paired-sets protocols separated by 72h, consisting of 4 sets of 10 repetitions. The protocols differed in terms of the rest interval between the knee flexion and extension movements: 0s (no rest); 60s and 120s. The rest intervals between exercise sets were standardized at 60s. Total work, peak torque, neuromuscular efficiency, surface EMG amplitude (sEMG, root mean square) and fatigue index obtained by processing of sEMG signal, were compared between rest intervals and exercise sets within each protocol. RESULTS: There were no significant differences between rest intervals for total work, peak torque and neuromuscular efficiency (P > 0.05), but significant differences were found for sEMG and fatigue (P < 0.01), in which the protocol with 60s interval resulted in greater fatigue. CONCLUSION: We showed that peak torque, total work and neuromuscular efficiency were not different between RI. The 60s RI showed a lower sEMG and a greater muscle fatigue. Although there were no significant differences, the NME was higher in the 60s interval.

Effects of different electrical stimulation currents and phase durations on submaximal and maximum torque, efficiency, and discomfort: a randomized crossover trial.

BACKGROUND: Neuromuscular electrical stimulation (NMES) is an important therapeutic tool for rehabilitation. However, best stimulation parameters remain to be determined. OBJECTIVE: To determine the influence of different electrical stimulation currents and phase durations on torque, efficiency, and discomfort. METHODS: Using a cross-over design, kHz frequency alternating currents (KFAC) and pulsed currents (PC) with narrow (200 µs) or wide (500 µs) phase durations were randomly applied on knee extensor muscles of healthy participants with a minimum of seven days between sessions. The NMES-evoked torque, NMES-efficiency, and discomfort (visual 0-10 cm analogue scale) were measured for each stimulation intensity increments (10 mA). Statistics were conducted using a three-way analysis of variances (phase duration x current x intensity), followed by Tukey post-hoc. RESULTS: Twenty-four males (age 22.3 ±â€¯3.5years) were included. No effect of NMES current was observed for torque, efficiency, and discomfort. For wide phase durations (500 µs), torque significantly increased for all stimulation intensities. For narrow phase durations (200 µs) evoked torque significantly increased only after 40% of maximal stimulation intensity. Phase durations of 500 µs produced greater torque than 200 µs. Discomfort was greater with 500 µs when compared to 200 µs. Submaximal relative torque, for example 40% of maximum voluntary contraction (MVC), was obtained with ∼ 60% and ∼ 80% of the maximal current intensity for 500 µs and 200 µs, respectively. CONCLUSION: KFAC and PC current applied with the same phase duration induced similar relative submaximal and maximum evoked-torque, efficiency, and perceived discomfort. However, currents with 500 µs induced higher evoked-torque, current efficiency, and perceived discomfort.

The effects of one session of roller massage on recovery from exercise-induced muscle damage: A randomized controlled trial.

BACKGROUND/OBJECTIVE: Roller massage has become a popular intervention in sports settings in order to treat muscle soreness and stiffness, as well as improving post-exercise recovery, although there is limited evidence for these assumptions. Therefore, the purpose of this study was to evaluate the effects of a single session of roller massage, applied with a controlled force after an exercise-induced muscle damage protocol, on muscle recovery. METHODS: A randomized controlled study was performed using a repeated-measures design. Thirty-six young men completed four sets of six eccentric actions of elbow flexors at 90°/s with a 90s rest interval between sets. Participants were randomly assigned into one of three groups: 1) Roller massage (n = 12), 2) Sham (n = 12), and 3) Control (n = 12). Maximal isometric voluntary contraction (MIVC), delayed-onset muscle soreness (DOMS), range of motion (ROM), and muscle thickness were measured at baseline, and at 24, 48, and 72 h post exercise. RESULTS: There was no significant group by time interaction for MIVC (p = 0.090) and ROM (p = 0.416). Also, although there was a significant group by time interaction for muscle thickness (p = 0.028), post hoc test did not find significant difference between groups (p > 0.05). DOMS was recovered at 72 h for roller massage (p < 0.001) and control (p < 0.001) groups, while the Sham group did not recover from DOMS across 72 h (p < 0.001). There was also no significant difference between groups in DOMS at any time (p > 0.05). CONCLUSIONS: A single session of roller massage applied on elbow flexors had no effect on recovery of MIVC, muscle swelling, ROM and DOMS.

Effect of strength training and antioxidant supplementation on perceived and performance fatigability in breast cancer survivors: a randomized, double-blinded, placebo-controlled study.

This randomized, double-blinded, placebo-controlled study aimed to investigate the effect of strength training (ST) combined with vitamin C and E supplementation on perceived and performance fatigability in breast cancer survivors (BCS). Twenty-five BCS were randomly assigned to 1 of 2 groups: vitamins (VIT; n = 12; 51.0 ± 9.0 years) or placebo (PLA; n = 13; 48.2 ± 8.3 years). Both groups performed a 10-week ST protocol, twice a week. The VIT group was supplemented with vitamins C (500 mg/day) and E (180 mg/day) and the PLA group with polydextrose (1 g/day), once a day after breakfast. At the beginning and at the end of the training period, perceived fatigability was assessed using Multidimensional Fatigue Inventory (MFI)-20 (general fatigue and physical fatigue). Performance fatigability was assessed during 30 maximal isokinetic knee extensions at 120°/s. General fatigue decreased similarly in the VIT (p = 0.004) and PLA (p = 0.011) groups. Physical fatigue decreased similarly in the VIT (p = 0.011) and PLA (p = 0.001) groups. Performance fatigability also decreased similarly in the VIT (p = 0.026) and PLA (p < 0.001) groups. There was no difference between groups at any moment (p > 0.05). In summary, antioxidant supplementation does not add any positive synergistic effect to ST in terms of improving perceived or performance fatigability in BCS. This clinical trial is registered in the Brazilian Clinical Trials Registry, number RBR-843pth (UTN no.: U1111-1222-6511). Novelty ST with maximal repetitions reduces perceived and performance fatigability of BCS. Vitamins C and E supplementation does not add any positive synergistic effect to ST in terms of reducing fatigability in BCS.

The Effects of Strength Training Combined with Vitamin C and E Supplementation on Skeletal Muscle Mass and Strength: A Systematic Review and Meta-Analysis.

Intense muscle contractile activity can result in reactive oxygen species production in humans. Thus, supplementation of antioxidant vitamins has been used to prevent oxidative stress, enhance performance, and improve muscle mass. In this sense, randomized controlled studies on the effect of vitamin C and E supplementation combined with strength training (ST) on skeletal muscle mass and strength have been conducted. As these studies have come to ambiguous findings, a better understanding of this topic has yet to emerge. The purpose of the present review is to discuss the current knowledge about the effect of vitamin C and E supplementation on muscle mass and strength gains induced by ST. Search for articles was conducted in the following databases: PubMed/Medline, Web of Science, Scopus, Cochrane Central Register of Controlled Trials, and Google Scholar. This work is in line with the recommendations of the PRISMA statement. Eligible studies were placebo-controlled trials with a minimum of four weeks of ST combined with vitamin C and E supplementation. The quality of each included study was evaluated using the Physiotherapy Evidence Database Scale (PEDro). 134 studies were found to be potentially eligible, but only seven were selected to be included in the qualitative synthesis. A meta-analysis of muscle strength was conducted with 3 studies. Findings from these studies indicate that vitamins C and E has no effect on muscle force production after chronic ST. Most of the evidence suggests that this kind of supplementation does not potentiate muscle growth and could possibly attenuate hypertrophy over time.

Once a Week Resistance Training Improves Muscular Strength in Breast Cancer Survivors: A Randomized Controlled Trial.

Background: Exercise has been shown to reduce adverse outcomes related to breast cancer. However, the rate of adherence to physical exercise is very low among breast cancer survivors (BCS). This study investigated the effects of high supervision ratio resistance training (RT), once a week for 8 weeks, on changes in body composition and muscular strength in BCS. Methods: Twenty-five female BCS undergoing hormone therapy were randomized into resistance training group (TG, n = 12) or control (CG, n = 13) group. The TG performed 8 weeks of supervised RT, with 1 trainer per volunteer, once a week. Body composition was evaluated by dual-energy X-ray absorptiometry, and muscle strength was evaluated by 10 repetition maximum (10 RM) for leg press (45°) and bench press exercises. A 1-way analysis of variance was used to compare within-group effects at pre- and post-intervention. An analysis of covariance test was used to compare post-intervention values, using pre-intervention measures as covariates. The effect size (ES) was calculated by Cohen's d. Results: The TG improved muscle strength in 10 RM leg press (45°; Δ 33.75 ± 11.51 kg, P = .02; ES = 0.96) and bench press (Δ 4.08 ± 1.83 kg, P = .01; ES = 1.15). Adherence to training was more than 99%. Changes in body composition were not detected. There were no changes in the CG for any assessment. Conclusion: Once-weekly supervised RT could be an alternative to increase the adherence to exercise and improve muscular strength in BCS.

Antioxidant Supplementation Impairs Changes in Body Composition Induced by Strength Training in Young Women.

Strength training (ST) is known to promote muscle hypertrophy and body composition adaptations. However, only a few studies investigated the effects of ST combined with antioxidant supplementation (AS) on these adaptations. The aim of this study was to investigate chronic effects of ST combined with AS on fat mass (FM) and fat-free mass (FFM) of young women. In a double-blinded design, thirty-three subjects (22.9 ± 2.5 years, 57.7 ± 8.4 kg, 1.6 ± 0.6 m) were allocated into three groups: 1) vitamins (n=12), 2) placebo (n=11) and 3) control (n=10). Vitamins and placebo underwent a ST program for 10 weeks. Vitamins supplemented with vitamin C (1g/day) and E (400IU/day) during the training period. FM and FFM were assessed by DEXA. Multiple 3 x 2 (group x time) mixed-factor ANOVA with Tukey adjustment was performed to examine differences in the dependent variables. The significance level was set at P ≤ .05. Only placebo increased total FFM (34.9 ± 4.9 vs 36.3 ± 4.8 kg, P<0.05) and decreased total FM (21.8 ± 7.8 vs 21.0 ± 8.3 kg, P<0.05) after training for 10 weeks. Moreover, only placebo presented a significantly greater FFM percent change from pre to post-intervention compared to control (4.0 ± 3.4 vs -0.7 ± 3.1%, respectively, P < 0.05). These results suggest that chronic AS can mitigate ST related improvements of body composition in young women.

Effect of strength training combined with antioxidant supplementation on muscular performance.

This was a placebo-controlled randomized study that aimed to investigate the effects of strength training (ST) combined with antioxidant supplementation on muscle performance and thickness. Forty-two women (age, 23.8 ± 2.7 years; body mass, 58.7 ± 11.0 kg; height, 1.63 ± 0.1 m) were allocated into 3 groups: vitamins (n = 15), placebo (n = 12), or control (n = 15). The vitamins and placebo groups underwent an ST program, twice a week, for 10 weeks. The vitamins group was supplemented with vitamins C (1 g/day) and E (400 IU/day) during the ST period. Before and after training, peak torque (PT) and total work (TW) were measured on an isokinetic dynamometer, and quadriceps muscle thickness (MT) was assessed by ultrasound. Mixed-factor ANOVA was used to analyze data and showed a significant group × time interaction for PT and TW. Both the vitamins (37.2 ± 5.4 to 40.3 ± 5.6 mm) and placebo (39.7 ± 5.2 to 42.5 ± 5.6 mm) groups increased MT after the intervention (P < 0.05) with no difference between them. The vitamins (146.0 ± 29.1 to 170.1 ± 30.3 N·m) and placebo (158.9 ± 22.4 to 182.7 ± 23.2 N·m) groups increased PT after training (P < 0.05) and PT was higher in the placebo compared with the control group (P = 0.01). The vitamins (2068.3 ± 401.2 to 2295.5 ± 426.8 J) and placebo (2165.1 ± 369.5 to 2480.8 ± 241.3 J) groups increased TW after training (P < 0.05) and TW was higher in the placebo compared with the control group (P = 0.01). Thus, chronic antioxidant supplementation may attenuate peak torque and total work improvement in young women after 10 weeks of ST.

A novel approach for rehabilitation of a triceps tendon rupture: A case report.

OBJECTIVE: Generate hypotheses and add new perspectives to the literature in the nonsurgical management of large ruptures in the distal part of the triceps tendon. METHODS: The patient was physically active, right handed, with a history of 20 years of resistance training practice and involvement in many activities, mostly combat sports (boxing, karate and mixed martial arts). The exercise program was designed with high repetitions and low rest intervals between sets in order to increase the metabolic stress. The resistance training with focus on tendon rehabilitation was performed in 28 weeks, with a follow-up of 52 weeks. The outcomes were changes in muscle strength and in the morphology of muscle and tendon. RESULTS: The results obtained in the isokinetic tests showed that the functional deficit was more evident during isometric than dynamic actions, and was also higher is slow than fast actions. Dynamic performance was fully recovered at the end of the follow up, while isometric strength did not. CONCLUSIONS: The present case reports a successful rehabilitation program after a near maximum triceps tendon rupture. The novelty was in the use of a simple resistance training program, that demanded low time commitment and was performed in a regular fitness facility.

Pre-exercise ß-hydroxy-ß-methylbutyrate free-acid supplementation improves work capacity recovery: a randomized, double-blinded, placebo-controlled study.

The purpose of this study was to investigate the effects of a single-dose of ß-hydroxy-ß-methylbutyrate free acid (HMB-FA) supplementation on muscle recovery after a high-intensity exercise bout. Twenty-three trained young males were randomly assigned to receive either a single-dose supplementation of 3 g of HMB-FA (n = 12; age, 22.8 ± 3.0 years) or placebo (PLA; n = 11; age, 22.9 ± 3.1 years). A muscle damage protocol was applied 60 min after supplementation, and consisted of 7 sets of 20 drop jumps from a 60-cm box with 2-min rest intervals between sets. Muscle swelling, countermovement jump (CMJ), maximal voluntary isometric torque (MVIT), and work capacity (WC) were measured before, immediately after, and 24, 48, and 72 h after the exercise protocol. Muscle swelling, CMJ, and MVIT changed similarly in both groups after the exercise protocol (p < 0.001), but returned to pre-exercise levels after 24 h in both groups. WC decreased similarly in both groups after the exercise protocol (p < 0.01). For HMB-FA, WC returned to pre-exercise level 24 h after exercise protocol. However, for PLA, WC did not return to pre-exercise level even 72 h after the exercise protocol. In summary, a single-dose of HMB-FA supplementation improved WC recovery after a high-intensity exercise bout. However, HMB-FA did not affect the time-course of muscle swelling, MVIT, and CMJ recovery.

Cancer-Related Fatigue and Muscle Quality in Hodgkin's Lymphoma Survivors.

The purpose of this study was to compare fatigue, strength, body composition, muscle thickness, and muscle quality between Hodgkin's lymphoma survivors (HLS) and apparently healthy subjects matched by age, gender, and physical activity levels (CON). Twelve HLS (32.16 ± 8.06) and 36 CON (32.42 ± 7.64) were enrolled in the study. Fatigue was assessed using the 20-item Multidimensional Fatigue Inventory, muscle strength using an isokinetic dynamometer, body composition using dual-energy X-ray absorptiometry, and thickness and muscle quality using B-mode ultrasound. Differences between HLS and CON were analyzed using independent samples t tests. No significant differences were observed between groups for any demographic characteristics: age ( P = .922), weight ( P = .943), height ( P = .511), body mass index ( P = .796), fat mass ( P = .688), fat-free mass ( P = .520), and percent body fat ( P = .446). No significant differences were observed for strength (peak torque; P = .552), relative peak torque ( P = .200), muscle thickness ( P > .05) and muscle quality ( P > .05). However, self-perceived fatigue was significantly higher in HLS than in CON ( P = .009). It appears that when HLS are matched by age and physical activity levels to CON, no significant difference in body composition, muscle thickness, muscle quality, or strength is observed. Self-perceived fatigue, as predicted, is higher in HLS, which may have implications and should be considered when prescribing exercise training to this cancer population.

Kilohertz and Low-Frequency Electrical Stimulation With the Same Pulse Duration Have Similar Efficiency for Inducing Isometric Knee Extension Torque and Discomfort.

OBJECTIVE: To test the hypotheses that, as compared with pulsed current with the same pulse duration, kilohertz frequency alternating current would not differ in terms of evoked-torque production and perceived discomfort, and as a result, it would show the same current efficiency. DESIGN: A repeated-measures design with 4 stimuli presented in random order was used to test 25 women: (1) 500-microsecond pulse duration, (2) 250-microsecond pulse duration, (3) 500-microsecond pulse duration and low carrier frequency (1 kHz), (4) 250-microsecond pulse duration and high carrier frequency (4 kHz). Isometric peak torque of quadriceps muscle was measured using an isokinetic dynamometer. Discomfort was measured using a visual analog scale. RESULTS: Currents with long pulse durations induced approximately 21% higher evoked torque than short pulse durations. In addition, currents with 500 microseconds delivered greater amounts of charge than stimulation patterns using 250-microsecond pulse durations (P < 0.05). All currents presented similar discomfort. There was no difference on stimulation efficiency with the same pulse duration. CONCLUSIONS: Both kilohertz frequency alternating current and pulsed current, with the same pulse duration, have similar efficiency for inducing isometric knee extension torque and discomfort. However, neuromuscular electrical stimulation (NMES) with longer pulse duration induces higher NMES-evoked torque, regardless of the carrier frequency. Pulse duration is an important variable that should receive more attention for an optimal application of NMES in clinical settings.

Effect of transcutaneous electrical nerve stimulation on peripheral to central blood pressure ratio in healthy subjects.

PURPOSE: To investigate the effect of transcutaneous electrical nerve stimulation (TENS) on the arterial stiffness in healthy young adult and middle-aged men using the augmentation index (AI-x) and hemodynamic measures. METHODS: Twenty-four men (12 aged 27·25 ± 5·53 years and 12 aged 54·83 ± 5·10 years) were randomly allocated to two subgroups: TENS or placebo in ganglion region for 45 min. The AI-x and hemodynamic measures [late systolic blood pressure (SBP), central blood pressure (CBP), difference between P1 and P2 (ΔP) and tension time index (TTI)] were determined before and after protocols. RESULTS: TENS resulted in reduction of SBP in younger adults (TENSpre: 111 ± 2; post: 105 ± 2·2 mm Hg; PLACEBOpre: 113 ± 1·8; post: 114 ± 2·5 mm Hg; GEE, P<0·01), whereas no difference was found in middle-aged group. TENS also resulted in reduction of AI-x younger adults group (TENSpre: 56 ± 2·8; post: 53 ± 2%; PLACEBOpre: 55 ± 3; post: 58 ± 2·5%; GEE, P<0·01). ΔP and TTI were significantly decreased after the application of TENS in both groups, but significantly greater reductions in TTI and the SBP/CBP ratio were found in the group of younger adults. CONCLUSIONS: The acute application of ganglion TENS attenuated arterial stiffness in younger adults as well as hemodynamic measures in the middle-aged group. This method could emerge as effective therapy for the management of arterial blood pressure.

Skinfold thickness affects the isometric knee extension torque evoked by Neuromuscular Electrical Stimulation

BACKGROUND: Subcutaneous adipose tissue may influence the transmission of electrical stimuli through to the skin, thus affecting both evoked torque and comfort perception associated with neuromuscular electrical stimulation (NMES). This could seriously affect the effectiveness of NMES for either rehabilitation or sports purposes. OBJECTIVE: To investigate the effects of skinfold thickness (SFT) on maximal NMES current intensity, NMES-evoked torque, and NMES-induced discomfort. METHOD: First, we compared NMES current intensity, NMES-induced discomfort, and NMES-evoked torque between two subgroups of subjects with thicker (n=10; 20.7 mm) vs. thinner (n=10; 29.4 mm) SFT. Second, we correlated SFT to NMES current intensity, NMES-induced discomfort, and NMES-evoked knee extension torque in 20 healthy women. The NMES-evoked torque was normalized to the maximal voluntary contraction (MVC) torque. The discomfort induced by NMES was assessed with a visual analog scale (VAS). RESULTS: NMES-evoked torque was 27.5% lower in subjects with thicker SFT (p=0.01) while maximal current intensity was 24.2% lower in subjects with thinner SFT (p=0.01). A positive correlation was found between current intensity and SFT (r=0.540, p=0.017). A negative correlation was found between NMES-evoked torque and SFT (r=-0.563, p=0.012). No significant correlation was observed between discomfort scores and SFT (rs=0.15, p=0.53). CONCLUSION: These results suggest that the amount of subcutaneous adipose tissue (as reflected by skinfold thickness) affected NMES current intensity and NMES-evoked torque, but had no effect on discomfort perception. Our findings may help physical therapists to better understand the impact of SFT on NMES and to design more rational stimulation strategies.