Rodrigo Luiz Carregaro

DISSOCIATED TIME COURSE OF RECOVERY BETWEEN GENDERS AFTER RESISTANCE EXERCISE

Flores, DF, Gentil, P, Brown, LE, Pinto, RS, Carregaro, RL, and Bottaro, M. Dissociated time course of recovery between genders after resistance exercise. J Strength Cond Res 25(11): 3039–3044, 2011—Comparisons between men and women of time course responses of strength, delayed-onset muscle soreness (DOMS), and muscle swelling after a resistance training session are still controversial. Therefore, this study examined gender differences in strength loss, muscle thickness (MT), and DOMS between young men and women. Thirty apparently healthy, untrained volunteers (14 women and 16 men) participated in the study protocol. The resistance exercise session consisted of 8 sets at 10 repetition maximum load of the elbow flexor muscles of their dominant arm. Maximum isokinetic peak torque (PT), MT, and DOMS were recorded at baseline (TB), immediately after exercise (T0), and at 1 (T1), 2 (T2), 3 (T3), and 4 (T4) days after exercise. Baseline strength was expressed as 100%. There were no significant differences between the sexes for relative PT loss immediately after exercise (T0 = 74.31 ± 8.26% for men and 76.00 ± 6.31% for women). Also, PT was still significantly less than baseline from T1 to T4 for both genders. In contrast, recovery from PT was longer in women when compared with that in men. Muscle thickness responded similarly to PT in both genders. However, there was no significant difference between genders for DOMS at any time point. The time point that showed the greatest degree of mean soreness was T2 (4.94 ± 2.38 mm for men and 4.45 ± 2.07 mm for women). Our data suggest that after resistance exercise, women and men experience similar immediate strength loss; however they have dissimilar strength recovery across 4 days of recovery. Likewise, both genders experience a different time course of MT response after a traditional resistance exercise protocol. In contrast, men and women develop and dissipate muscle soreness in a similar manner.

Effects of antagonist pre-load on knee extensor isokinetic muscle performance

Abstract The aim of this study was to evaluate and compare acute effects of a reciprocal action protocol and a super-set protocol on knee extensor performance during concentric isokinetic exercise. Fourteen men aged 29.4 ± 6.1 years were tested on three different protocols, with 1 min of rest between sets: control (3 sets of 10 isokinetic knee extension repetitions), reciprocal action protocol (3 sets of 10 repetitions of reciprocal isokinetic concentric knee flexion and knee extension repetitions), and super-set protocol (3 sets of a combination of 10 repetitions of knee flexion immediately followed by 10 repetitions of knee extension repetitions). Tests were performed at 60° · s−1 and 180° · s−1, randomized across 3 days and separated by at least 72 h. There were no significant differences between protocols for peak torque at 60° · s−1 or 180° · s−1. Total work was significantly higher during the reciprocal action protocol compared with the super-set protocol at 60° · s−1. There was a significant decline in peak torque (from 240.6 to 212.9 N · m) and total work (from 2294 to 1899 J) for the control condition at 60° · s−1. Also, total work declined significantly across sets for the super-set protocol at 60° · s−1 (from 2157 to 1707 J). Results indicate that a reciprocal action protocol provides torque maintenance during multiple sets of isokinetic training, both at slow and high velocities.

Effects of different methods of antagonist muscles pre-activation on knee extensors neuromuscular responses

BACKGROUND Pre-activation of antagonistic muscles is used in different modalities of exercise and neuromuscular rehabilitation protocols, but its effectiveness is still controversial. OBJECTIVE To verify the impact of two different methods of pre-activation of knee antagonist muscles in the neuromuscular performance and electromyographic activity of knee extensors. METHODS Fifteen healthy men (23.9±4.2 years of age, 1.78±0.08 meters and 81.4±10.7 kg) performed, on different days, two protocols of isokinetic muscle contraction with 4 sets of 10 repetitions at 60°.s-1 and 1 minute between sets: (1) Reciprocal Contraction (RC): reciprocal concentric exercise of agonist/antagonist muscles (knee flexion [KF] immediately followed by knee extension [KE]) and (2) Superset (SS): alternated concentric exercise of agonist/antagonist muscles (KF set followed by a set of KE). A repeated measures ANOVA with least-significant difference post-hoc test was used to detect differences between protocols. RESULTS There were no significant differences between protocols (p>0.05) for peak torque (PT) and total work (Tw). On the SS protocol there was a significant decrease in Tw on the last two sets (p<0.05) while for RC the decrease occurred only in the last set. There were no significant differences of root mean square (RMS) between protocols, but the activation pattern was more uniform during the RC protocol. CONCLUSION The results indicated that the peak torque was not influenced by the different pre-activation methods. However, the RC protocol appears to better maintain the total work training volume.

Muscle fatigue and metabolic responses following three different antagonist pre-load resistance exercises

PURPOSE Preload of antagonist muscles can be achieved by reciprocal actions (RAs) or by opposing muscle actions. However, evidence concerning neuromuscular and fatigue responses are scarce. OBJECTIVE To compare the effects of different knee flexor (KF) preload methods on knee extension (KE) vastus medialis muscle fatigue, based on EMG-spectral index (FI), load range (LR), total work (TW), blood lactate (LAC) and biceps femoris co-activation (BFc) during resistance exercise. METHODS Twenty-four healthy men (23.5±3.6yrs) performed three antagonist pre-load isokinetic exercises (4 sets, 10 repetitions, 60°s(-1), 1min rest between sets): RA (KF contraction immediately followed by KE); Superset (SS; one KF set immediately followed by one KE set); Multiple Set (MS; four KF sets followed by four KE sets). RESULTS Total work was significantly greater in RA. There was no significant decrease in LR between sets in RA. The BFc did not differ between protocols (p=0.063). However, RA presented greater biceps femoriscoactivation. The FI was greater during SS compared to RA and MS (p<0.05). The SS had greater LAC when compared to MS and RA (p=0.005 and p=0.007, respectively). CONCLUSION It is suggested that the RA protocol is more neuromuscular and metabolic efficient during the performance of knee extension resistance exercise.

Effects of 20 sessions of Pilates method on postural alignment and flexibility of young women: pilot study

The aim of the study was to evaluate the effects of Mat Pilates in the postural alignment and joint flexibility of healthy young females. Thirty-three healthy women aged between 18 and 30 years (56.8±8.5 kg, 1.60±0.06 m and 22.1±2.7 kg/m2) and without prior knowledge of Pilates participated of the study. They were randomly allocated into two groups: control group (CG; without intervention) and Pilates group (PG; Mat Pilates, 20 sessions, 2 times a week). Pre- and post-program evaluation procedures were performed by a blinded investigator and were characterized by photogrammetric postural analysis (PAS software) and assessment of joint flexibility (sit and reach test). A 2X2 repeated measures Analysis of Variance (ANOVA) was used to verify differences between pre- and post-measurements for both CG e PG. No significant differences were found between groups, for all variables. The PG presented no differences in postural alignment after the program (p>0.05). However, the PG demonstrated a significant increase of 19.1% in flexibility (p=0.036). The study demonstrated that a program of Mat Pilates generates significant effects on joint flexibility. However, twenty sessions were not sufficient to cause postural adaptations in healthy young women.The aim of the study was to evaluate the effects of Mat Pilates in the postural alignment and joint flexibility of healthy young females. Thirty-three healthy women aged between 18 and 30 years (56.8±8.5 kg, 1.60±0.06 m and 22.1±2.7 kg/m²) and without prior knowledge of Pilates participated of the study. They were randomly allocated into two groups: control group (CG; without intervention) and Pilates group (PG; Mat Pilates, 20 sessions, 2 times a week). Pre- and post-program evaluation procedures were performed by a blinded investigator and were characterized by photogrammetric postural analysis (PAS software) and assessment of joint flexibility (sit and reach test). A 2X2 repeated measures Analysis of Variance (ANOVA) was used to verify differences between pre- and post-measurements for both CG e PG. No significant differences were found between groups, for all variables. The PG presented no differences in postural alignment after the program (p>;0.05). However, the PG demonstrated a significant increase of 19.1% in flexibility (p=0.036). The study demonstrated that a program of Mat Pilates generates significant effects on joint flexibility. However, twenty sessions were not sufficient to cause postural adaptations in healthy young women.

Pilates versus general exercise effectiveness on pain and functionality in non-specific chronic low back pain subjects

Low back pain (LBP) is one of the most common causes of disability, and the Pilates method has been associated with improvements in symptoms. The purpose of this study was to assess the effectiveness of the Pilates method, when compared to general exercises, on pain and functionality after eight weeks (16 sessions, 2×/week) and a follow-up of three months, in subjects with non-specific chronic low back pain (NSCLBP). A randomised controlled trial composed of 22 subjects was proposed. Subjects were allocated into two groups: the Pilates group (PG) (n = 11) and the general exercise group (GEG) (n = 11). The PG protocol was based on the Pilates method and the GEG performed exercises to manage NSCLBP. There were no differences between the groups. When analysed over time, the GEG demonstrated improvements in functionality between baseline and the end of treatment (P = .02; Cohensd¯ = 0.34) and baseline and follow-up (P = .04; Cohensd¯ = 0.31). There were no differences between the Pilates and general exercises with regard to pain and functionality in NSCLBP subjects but general exercises were better than Pilates for increasing functionality and flexibility.

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.

Do virtual reality games improve mobility skills and balance measurements in community-dwelling older adults? Systematic review and meta-analysis

Objective: To summarize evidence on the effectiveness of virtual reality games and conventional therapy or no-intervention for fall prevention in the elderly. Data sources: An electronic data search (last searched December 2016) was performed on 10 databases (Web of Science, EMBASE, PUBMED, CINAHL, LILACS, SPORTDiscus, Cochrane Library, Scopus, SciELO, PEDro) and retained only randomized controlled trials. Review method: Sample characteristics and intervention parameters were compared, focusing on clinical homogeneity of demographic characteristics, type/duration of interventions, outcomes (balance, reaction time, mobility, lower limb strength and fear of falling) and low risk of bias. Based on homogeneity, a meta-analysis was considered. Two independent reviewers assessed the risk of bias. Results: A total of 28 studies met the inclusion criteria and were appraised (n: 1121 elderly participants). We found that virtual reality games presented positive effects on balance and fear of falling compared with no-intervention. Virtual reality games were also superior to conventional interventions for balance improvements and fear of falling. The six studies included in the meta-analysis demonstrated that virtual reality games significantly improved mobility and balance after 3–6 and 8–12 weeks of intervention when compared with no-intervention. The risk of bias revealed that less than one-third of the studies correctly described the random sequence generation and allocation concealment procedures. Conclusion: Our review suggests positive clinical effects of virtual reality games for balance and mobility improvements compared with no-treatment and conventional interventions. However, owing to the high risk of bias and large variability of intervention protocols, the evidence remains inconclusive and further research is warranted.

Efeitos de 20 sessões do método Pilates no alinhamento postural e flexibilidade de mulheres jovens: estudo piloto

The aim of the study was to evaluate the effects of Mat Pilates in the postural alignment and joint flexibility of healthy young females. Thirty-three healthy women aged between 18 and 30 years (56.8±8.5 kg, 1.60±0.06 m and 22.1±2.7 kg/m2) and without prior knowledge of Pilates participated of the study. They were randomly allocated into two groups: control group (CG; without intervention) and Pilates group (PG; Mat Pilates, 20 sessions, 2 times a week). Pre- and post-program evaluation procedures were performed by a blinded investigator and were characterized by photogrammetric postural analysis (PAS software) and assessment of joint flexibility (sit and reach test). A 2X2 repeated measures Analysis of Variance (ANOVA) was used to verify differences between pre- and post-measurements for both CG e PG. No significant differences were found between groups, for all variables. The PG presented no differences in postural alignment after the program (p>0.05). However, the PG demonstrated a significant increase of 19.1% in flexibility (p=0.036). The study demonstrated that a program of Mat Pilates generates significant effects on joint flexibility. However, twenty sessions were not sufficient to cause postural adaptations in healthy young women.The aim of the study was to evaluate the effects of Mat Pilates in the postural alignment and joint flexibility of healthy young females. Thirty-three healthy women aged between 18 and 30 years (56.8±8.5 kg, 1.60±0.06 m and 22.1±2.7 kg/m²) and without prior knowledge of Pilates participated of the study. They were randomly allocated into two groups: control group (CG; without intervention) and Pilates group (PG; Mat Pilates, 20 sessions, 2 times a week). Pre- and post-program evaluation procedures were performed by a blinded investigator and were characterized by photogrammetric postural analysis (PAS software) and assessment of joint flexibility (sit and reach test). A 2X2 repeated measures Analysis of Variance (ANOVA) was used to verify differences between pre- and post-measurements for both CG e PG. No significant differences were found between groups, for all variables. The PG presented no differences in postural alignment after the program (p>;0.05). However, the PG demonstrated a significant increase of 19.1% in flexibility (p=0.036). The study demonstrated that a program of Mat Pilates generates significant effects on joint flexibility. However, twenty sessions were not sufficient to cause postural adaptations in healthy young women.

Kinematic Gait Analysis Using Inertial Sensors with Subjects after Stroke in Two Different Arteries

[Purpose] The aim of the present study was described the kinematic characteristics of gait in stroke patients with two different arteries involved. [Subjects and Methods] Two patients who had suffered a basilar (A) or middle (B) cerebral artery ischemic stroke were compared with a control (C). Seventeen inertial sensors were used with acquisition rate of 120 Hz. The participants walked 3 times on a 10 meter walkway. From the raw data, the three gait cycles from the middle of each trial were chosen and analyzed. [Results] During the stance phase, patients A and B had a lower hip angle at initial contact and maximum flexion angle during load response than the control. Patient A and the control subject had similar knee angle values at initial contact, and patient B presented a flexed position in the initial phase of the gait cycle. The maximum flexion angles during loading response were also higher for patient B. The sagittal plane excursion for the ankle joint was lower for patient B in comparison with the other subjects. [Conclusion] Differences during walking between patients who had stroke in different arteries may be related to an alternative compensatory strategy. Patient A and the control subject had similar gait cycle curves at all joints, while patient B showed a rigid synergic pattern.