Naryana Cristina Mascarin

Isokinetic hamstrings-to-quadriceps peak torque ratio: The influence of sport modality, gender, and angular velocity

Abstract The purpose of this study was to determine differences in hamstrings-to-quadriceps (H/Q) peak torque ratios evaluated at different angular velocities between men and women who participate in judo, handball or soccer. A total of 166 athletes, including 58 judokas (26 females and 32 males), 39 handball players (22 females and 17 males), and 69 soccer players (17 females and 52 males), were evaluated using an isokinetic dynamometer. The H/Q isokinetic peak torque ratios were calculated at angular velocities of 1.05 rad · s−1 and 5.23 rad · s−1. In the analysis by gender, female soccer players produced lower H/Q peak torque ratios at 1.05 rad · s−1 than males involved in the same sport. However, when H/Q peak torque ratio was assessed at 5.23 rad · s−1, there were no significant differences between the sexes. In the analysis by sport, there were no differences among females at 1.05 rad · s−1. In contrast, male soccer players had significantly higher H/Q peak torque ratios than judokas (66 ± 12% vs. 57 ± 14%, respectively). Female handball players produced significantly lower peak torque ratios at 5.23 rad · s−1 than judokas or soccer players, whereas males presented no ratio differences among sports At 5.23 rad · s−1. In the analysis by velocity, womens muscular ratios assessed at 1.05 rad · s−1 were significantly lower than at 5.23 rad · s−1 for all sports; among men, only judokas presented lower ratios at 1.05 rad · s−1 than at 5.23 rad · s−1. The present results suggest that sport modality and angular velocity influence the isokinetic strength profiles of men and women.

Effects of kinesiotherapy, ultrasound and electrotherapy in management of bilateral knee osteoarthritis: prospective clinical trial.

BackgroundAlthough recent advances in knee osteoarthritis (OA) treatment and evaluation were achieved, to the best of our knowledge, few studies have evaluated the longitudinal effect of therapeutic modalities on the functional exercise capacity of patients with knee OA. The purpose was to investigate the effects of kinesiotherapy and electrotherapy on functional exercise capacity, evaluated using the six-minute walk test (6-MWT) in patients with bilateral knee OA. Secondary measurements included range of motion (ROM), severity of knee pain (VAS), and a measure of perceived health and physical function, evaluated using the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index.MethodsA total of 40 women with bilateral knee OA were assigned to three groups: kinesiotherapy (KIN, n = 16), transcutaneous electrical nerve stimulation (TENS, n = 12), or ultrasound (US, n = 10). The groups underwent 12 weeks of intervention twice per week. The participants were subjected to the 6-MWT, ROM, VAS and WOMAC index. These tests were performed before and after the intervention. The study was focused on outpatients and was carried out at Universidade Estadual de Campinas, Brazil.ResultsAt follow-up, the KIN and US groups had significantly higher 6-MWT distances (19.8 ± 21.7 and 14.1 ± 22.5%, respectively) compared with their respective pre-intervention values. All treatments were effective for reducing pain and improving the WOMAC index.ConclusionsWe demonstrated that the 6-MWT is a tool that can be used to evaluate improvements in the functional exercise capacity of patients submitted to a clinical intervention.

Shoulder isokinetic profile of male handball players of the Brazilian National Team

Background Data obtained on an isokinetic dynamometer are useful to characterize muscle status and have been reported in muscle imbalance studies in different types of sport. However, few studies have assessed elite handball players to establish reference values. Objective The purpose of this study was to compare, for the dominant (D) and non-dominant (ND) side, the isokinetic profile of shoulder rotator muscle strength between male handball players (H) and asymptomatic non-athletes (NA). Method Isokinetic concentric and eccentric strength tests for D upper limbs were performed by the H group (n=20) and the NA group (n=12). Internal and external rotator muscle peak torque in concentric action was assessed at 60°/s and 300°/s and in eccentric action at 300°/s. We also calculated conventional balance (the ratio of external rotator peak torque to internal rotator peak torque in concentric action) and functional balance (the ratio of external rotator peak torque in eccentric action to internal rotator peak torque in concentric action). Results In the H group, dominant limbs were stronger in concentric action for external rotation at 60 and 300°/s. The conventional balance ratio for the D side was significantly lower at 60 and 300°/s for H compared to NA. The functional ratio for the D side was significantly lower at 300º/s for H compared to NA. Conclusions Compared to asymptomatic non-athletes, handball players presented significant muscular imbalance resulting from daily sports practice, a known risk factor for shoulder injuries.

Stretch-Induced Reductions in Throwing Performance Are Attenuated by Warm-up Before Exercise.

Abstract Mascarin, NC, Vancini, RL, Lira, CAB, and Andrade, MS. Stretch-induced reductions in throwing performance are attenuated by warm-up before exercise. J Strength Cond Res 29(5): 1393–1398, 2015—Recent investigations have suggested that static stretching (SS) performed before exercise reduces muscular performance. However, it is yet unknown whether dynamic warm-up exercises performed together with SS may actually minimize the detrimental acute effects of stretching on muscular performance. This study aimed to assess the effects of static shoulder stretching exercises, dynamic warm-up exercises, or both together, on muscular performance evaluated by ball throwing. Twenty-one female handball players (age: 16.2 ± 1.0 years [range: 14–18 years], height: 167.0 ± 10.0 cm [range: 158–179 cm], and body mass: 63.3 ± 7.6 kg [range: 50.4–77.4 kg]) performed SS, dynamic warm-up exercises or both, targeting the muscles of the upper limbs. Thereafter, medicine ball throwing distance and handball ball throwing speed tests were performed. Static stretching performed before the medicine ball throwing test reduced performance when compared with the warm-up exercises (95% confidence interval [CI] = 0.02–0.17, p ⩽ 0.05, effect size [ES] = 0.34). When a warm-up exercise routine was added to SS, the detrimental effects of SS were abolished (95% CI = −0.01 to 0.18, p > 0.05, ES = 0.31). The throwing speed was the same over the 3 conditions. In conclusion, warm-up exercises performed together with SS abolished the impairment in medicine ball throwing distance. We recommend that athletes perform warm-up exercises together with SS before activity to avoid detrimental effects on muscle strength.

Strength Training Using Elastic Band Improves Muscle Power and Throwing Performance in Young Female Handball Players

CONTEXT Imbalance in shoulder-rotator muscles has been considered a risk factor for injuries in handball. Strength training programs (STPs) may play an important preventive role. OBJECTIVE To verify the effects of an STP using elastic bands on shoulder muscles and ball-throwing speed. DESIGN Randomized and prospective controlled trial. SETTING Exercise physiology laboratory. PARTICIPANTS Thirty-nine female handball players were randomly assigned to an experimental (EG, n = 21, 15.3 ± 1.1 y) or a control (CG, n = 18, 15.0 ± 0.8 y) group. INTERVENTION The EG performed the STP with elastic-band progressive exercises for 6 wk before regular handball training, and the CG underwent only their regular training. MAIN OUTCOME MEASURES Before and after the STP, both groups underwent a ball-throwing-speed test and isokinetic test to assess shoulder internal- (IR) and external-rotator muscle performance. RESULTS Average power values for IR muscles presented a significant group-vs-time interaction effect (F = 3.9, P = .05); EG presented significantly higher values after the STP (P = .03). Ball speed presented higher values in EG after the STP in standing (P = .04) and jumping (P = .03) throws. IR peak-torque values and balance in shoulder-rotator muscles presented no group-vs-time interaction effect. CONCLUSIONS STP using elastic bands performed for 6 wk was effective to improve muscle power and ball speed for young female handball players.