American Journal of Sports Science and Medicine

This study aimed to examine the differences in decreasing force during maximal sustained hand grip and toe grip exertions values. Fourteen males aged 18 to 22 years old performed hand and toe grip exertions for 6min. The sustained times of forces 40, 60, 70, and 80% of maximal strength (max), strength values at 90sec and 3min, and final strength value (% of max) were selected as evaluation parameters. The forces (% max) during both sustained grip exertions markedly decreased until about 60sec from their exertion onset, after which they slowly decreased, then decreased very little at 4-6min. Toe grip exertion values were significantly larger than hand grip exertion values until after 60sec from exertion onset (about 15% ～ 20% vs about 30% ～ 35%). Correlations among sustained time parameters (60%～80% max) were significant (r =0.657～0.960). The strength at 3 min in toe grip exertion significantly correlated to final strength, sustained time of forces 40% of max, and strength at 90sec. In summary, the forces during sustained hand grip and toe grip exertions show a similar decreasing tendency, but the latter’s exertion values maintain a higher level than the former’s after a marked decrease. The strength value at 3min for toe grip exertion may be useful as muscle endurance parameter.

American Journal of Sports Science and Medicine. 2013, 1(2), 28-32. DOI: 10.12691/ajssm-1-2-3
Pub. Date: July 24, 2013

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Overestimated Effect of Epo Administration on Aerobic Exercise Capacity: A Meta-Analysis

by Hein F.M. Lodewijkx, Bram Brouwer, Harm Kuipers and René van Hezewijk

Original Research

Recent studies examining the relationship between epo doping and aerobic performance (the EDAP–relationship) yield conflicting results. To resolve this inconclusiveness in an empirical way, we conducted a meta–analysis on 17 laboratory studies and assessed effect sizes (unbiased d, r and r²) of the epo–induced improvements in aerobic exercise capacity measured by maximal oxygen uptake (VO_2max) and maximal aerobic power output (W_map). The fixed, pooled EDAP effect size estimates were moderate, d = 0.41–0.49, r = .19–.44, and r²= .04–.19, revealing a shift of approximately half SD in performances of the epo–treated compared to the non–treated participants. As to VO_2max, we observed the strongest post test performance (M = 64.39ml kg^-1 min^-1) in double blind, placebo controlled studies on performances assessed at sea level with an increase from pre to post tests of M = 4.02ml kg-1 min-1. Regarding W_map, the increase was M = 26W with the strongest post test performance of M = 398W observed in similar studies as VO_2max. Percents improvement from pre to post tests varied between M = 6–7% (VO_2max), and M = 7–8% (W_map). The largest improvement in VO_2max we found equals an increase in velocity of about 1km/h. Consistent with recent studies criticizing the EDAP-relationship our findings indicate that its strength is overestimated. In turn, this entails that the relationship between epo doping and cyclists’ performances at real contests is overrated too.

American Journal of Sports Science and Medicine. 2013, 1(2), 17-27. DOI: 10.12691/ajssm-1-2-2
Pub. Date: May 05, 2013

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Effect of Training on Selected Biochemical Variables of Elite Male Swimmers

by Indranil Manna and Gulshan Lal Khanna

Original Research

The aim of the present study was to find out the effect of training on biochemical variables of elite male swimmers. A total of 60 Indian elite male swimmers (age: 17.33 ± 1.47 yrs; height: 173.08 ± 5.80 cm; body mass: 68.11 ± 5.02 kg) who regularly participate in competitive swimming volunteered for this study. A well-designed training program for the swimmers was employed for 12 weeks. The training sessions were divided into 2 phases (a) Preparatory Phase (PP, 8 weeks) and (b) Competitive Phase (CP, 4 weeks). Each phase was further subdivided into macro cycles and micro cycles, and were completed 4 hr/d; 5 d/wk. Selected variables were measured at zero level (baseline data, BD) and at the end of preparatory phase (PP) and competitive phase (CP) of training. A significant increase (P < 0.05) in serum urea, uric acid, high density lipoprotein cholesterol (HDL-C) was observed after training. On the other hand, a significant reduction (P < 0.05) in resting and peak blood lactate, hemoglobin, total cholesterol (TC), triglyceride (TG) and low density lipoprotein cholesterol (LDL-C), TC/HDL and LDL/HDL were noted after the conclusion of training. The training program was effective for improving selected biochemical parameters for swimmers, and may be employed for monitoring training.

American Journal of Sports Science and Medicine. 2013, 1(2), 13-16. DOI: 10.12691/ajssm-1-2-1
Pub. Date: May 04, 2013

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