Four Weeks of Supplementation With Isolated Soy Protein Attenuates Exercise-Induced Muscle Damage and Enhances Muscle Recovery in Well Trained Athletes: A Randomized Trial.

BACKGROUND: The effects of consumption of isolated soy protein (ISP) for a chronic period (4 weeks) on exercise induced muscle damage (EIMD) in athletic population have never been explored. OBJECTIVES: To examine the effects of ISP on muscle damage indices elicited via a bout of damaging exercise. PATIENTS AND METHODS: Forty males (20 boxers, 20 cyclists) aged 18 - 28 years were randomly assigned to two groups (ISP and Placebo) (n = 20). All participants who engaged themselves in specific, regular training of 30 hours a week during the competitive season were included in the study. Participants consumed the supplement and the placebo for 4 weeks. The damaging exercise consisted of 100 consecutive drop-jumps. Pre and post supplementation readings of the criterion variables, highly sensitive C reactive protein (hs-cRP), creatine Kinase (CK), myeloperoxidase (MPO), isometric muscle strength, maximum aerobic capacity (VO2 max), heart rate (HR) and muscle soreness were obtained at baseline (Day 1), at 24 hours (Day 2) and at 48 hours (Day 3) following EIMD. RESULTS: Differences were observed in pre and post supplementation values (P < 0.05) indicating the effectiveness of soy protein in attenuating muscle damage and enhancing muscle recovery. CONCLUSIONS: Our findings suggest that soy protein; a vegetable based supplement is effective, in ameliorating the negative effects of EIMD in trained athletic population.

Role of biofeedback in optimizing psychomotor performance in sports.

PURPOSE: Biofeedback is an emerging tool to acquire and facilitate physiological and psychological domains of the human body like response time and concentration. Thus, the present study aims at determining the reconstitution of psychomotor and performance skills in basketball players through biofeedback training. METHODS: Basketball players (N=30) with different levels of expertise (university, state and national) aged 18-28 years (both male and female) were randomly divided into 3 equal groups - Experimental group, Placebo group and Control group. The experimental group received Heart Rate Variability Biofeedback training for 10 consecutive days for 20 minutes that included breathing at individual's resonant frequency through a pacing stimulus; Placebo group was shown motivational video clips for 10 consecutive days for 10 minutes, whereas Control group was not given any intervention. At session 1, 10 and 1month follow up, heart rate variability, respiration rate, response time (reaction and movement time), concentration and shooting performance were assessed. RESULTS: Two way repeated measure ANOVA was used to simultaneously compare within and between group differences. Response time, concentration, heart rate variability, respiration rate and shooting differences were statistically significant in each group along with interaction of group and time (P<0.001). Also, all the measures showed statistically significant inter group difference (P<0.05). CONCLUSION: The results of the study suggest that biofeedback training may help to train stressed athletes to acquire a control over their psychophysiological processes, thus helping an athlete to perform maximally.

Functional performance testing in athletes with functional ankle instability.

PURPOSE: To determine if functional performance deficits are present in athletes with functional ankle instability (FAI) compared to healthy athletes using various functional performance tests. METHODS: Sixty two athletes (mean age-21.7±1.8years; height-168.2±9.1cm; weight-63.8±11.0kg) participated in this case control study. Athletes were divided into two groups: athletes with FAI (FAI group, n=31) and healthy athletes (Non-FAI group, n=31). The FAI group was further divided into two subgroups: FAI with giving way (FAI-GW), FAI with no giving way (FAI-NGW). Functional performance was assessed with the single-limb hopping test, figure-of-8 hop test, side-hop test, single-limb hurdle test, square hop test and single hop test. RESULTS: Significant differences (P<0.05) were observed for all the functional performance tests (FPTs) except the single hop test between FAI and Non-FAI groups; between FAI-GW, FAI-NGW and Non-FAI groups. Additionally, the involved limb performed significantly worse (P<0.05) than the contra-lateral uninvolved limb of the FAI-GW group for the above-mentioned FPTs. CONCLUSION: Significant functional performance deficits were observed in the FAI group in all tests except single hop test with greater deficits observed in the FAI-GW group. Hence, these tests can be used to determine the presence of FAI. However no deficits were identified for the test involving sagittal plane functional activities suggesting that this test can not be used as a criterion to discriminate individuals with FAI. It was further ascertained that functional performance was not affected by limb dominance.

The magnitude of pre-programmed reaction dysfunction in back pain patients: experimental pilot electromyography study.

BACKGROUND: Preprogrammed reactions (PPR) appear at a latency of higher than 40 ms, but before the voluntary muscle responds (approximately 120 ms) to postural perturbations. OBJECTIVE: To examine the difference in magnitude of preprogrammed reactions in patients with chronic low back pain (CLBP) and without low back pain. METHODS: we analyzed electromyographic Root Mean Square (RMS) amplitudes of asymptomatic (n=25) and CLBP patients (n=25) on stable and unstable surfaces during expected and unexpected perturbations for rectus abdominus and erector spinae muscles. The mean PPR and PPR-combined voluntary response RMS amplitudes (VRPPR) were compared between the two groups. To find the presence of PPR in LBP patients, a criteria was set that the obtained PPR RMS amplitude value should exceed 60% mean reflex RMS amplitude that occur within 50 ms after perturbation. RESULTS: Fleiss' kappa revealed a good agreement (kappa = 0.7 to 0.9) among raters for absence of PPR in patients with CLBP and presence of PPR in asymptomatic population. The two way ANOVA revealed significantly different mean PPR and VRPPR RMS amplitudes between asymptomatic and LBP population for rectus abdominus and erector spinae muscles (p<0.05). CONCLUSION: PPR responses were found absent (<60% of Mean Reflex RMS) in patients with CLBP. Further, patients with CLBP demonstrated lower PPR amplitudes with higher peak voluntary responses compared to asymptomatic population, indicating difficulties in presetting of voluntary responses for regaining postural stability after perturbation.