The aim of this study is to determine the capacity and the variability of maximum force rules measured 1 RM for eight muscle groups (back-hip extensors, legs extensors, arm extensors, back extensors, shoulder and arms extensors, shoulder joint flexors, hip and knee extensors, trunk flexors). The determination was performed on the experimental results of the top basketball center player using repeated measurements and nonlinear mathematical models methods. Changes in maximum force were induced with 8 months of weight lifting training and analised with nonlinear regression analysis within 95% confidence interval. The results indicate that from all the models applied only the Asymptotic Regression, Michaelis-Menten and Gompertz Growth models had satisfactory performance and provided solid solutions to the given problem. This means that the models developed in this study properly and reliably determine the capacity and predicted changes in the maximum force (1 RM) for all eight monitored muscle groups.
Abstract. The main aim of the present study was to investigate the effects of soccer-specific training on physical fitness components in adolescent elite soccer players and make comparisons with older counterparts. Twenty two male soccer players from the Serbian First Division team were allocated to two assigned trials according to age -young group (YG) and mature group (MG). Players in their teenage years (19 years and younger) were assigned to YG (10 subjects) and others to MG (12 subjects). Between the first and second test session, all subjects followed six weeks of soccer-specific periodized training programme. There were no differences between groups at pre-and post-training trial for body mass, vertical jump height, average anaerobic power and VO 2max (P>0.05). Body fat was significantly lower in YG before and after training program as compared to MG (P<0.05). Body mass and fat dropped significantly in both groups after training program (P<0.05). Furthermore, average anaerobic power and VO 2max along with vertical jump height, were significantly improved in both groups (P<0.05) at posttraining performance. Finally, the magnitude of change in VO 2max was significanty superior in MG as compared to YG after training program (18.3 vs. 7.8%; P<0.05). The findings of the present study indicate that the trainability indices are not highly influenced by age in top-level soccer players.(Biol.Sport 26:379-387, 2009)
The main aim of this investigation was to evaluate the changes in total antioxidant capacity (TAC) and aerobic and anaerobic performance induced by supplementation of coffeeberry (CB) formulation for 4 weeks in college athletes. Twenty college athletes (14 males and 6 females) were allocated to two randomly assigned trials. Subjects in the CB group orally ingested capsules that contained CB formulation at a dose of 800 mg per day in two equal doses for 28 days, while subjects in the placebo (P) group ingested an equal number of identical-looking caps that contained cellulose. There were no changes in glucose, cholesterol, and lipoproteins within or between trials (p > 0.05). Total antioxidant capacity (TAC) was significantly higher in the CB versus P trial at the post- supplementation trial (1.66 +/- 0.16 vs. 1.51 +/- 0.05 mmol/L; p < 0.05). There were no statistically significant changes in average anaerobic power, index of anaerobic fatigue, maximal heart rate, blood lactate, and maximal oxygen uptake within or between trials (p > 0.05). Heart rate recovery (HRR) index increased significantly in CB group as compared with baseline level (38 +/- 4 vs. 32 +/- 5 beats/min; p < 0.05). Blood lactate after 10 min of recovery (Lact(rec)) significantly decreased in the CB group after supplementation protocol as compared with initial results (7.6 +/- 4.2 vs. 5.5 +/- 2.6 mmol/L; p < 0.05). No subject reported any side effects from CB or P. The results of the present study indicate that supplementation with a CB formulation slightly increased antioxidant capacity, but there were minimal effects on recovery parameters after exercise in college athletes.
IntroductionMenopause is an independent risk factor for cardiovascular disease (CVD). Physical exercise and soybean diets have been suggested to reduce the risk of CVD in postmenopausal women. The purpose of this study was to investigate the effects of combined resistance and endurance (RE) training and soy extract (SOY) supplementation, both known to improve endothelial function, on expression of the eNOS gene in the heart of ovariectomized (OVX) rats.Material and methodsFifty female Wistar rats were divided into five groups: 1) sham (SHAM); 2) ovariectomy (OVX); 3) ovariectomy with soy extract supplementation (OVX + SOY); 4) OVX with RE training (OVX + RE); 5) and ovariectomy plus RE training with soy extract supplementation (OVX + RE + SOY). RE training and soy extract supplementation were administered alone or in combination for 6 weeks. The effects of these treatments on cardiac eNOS expression were measured using real-time PCR.ResultsOvariectomy down-regulated cardiac eNOS gene expression; however, 6 weeks of SOY treatment or RE training reversed this effect (p ≤ 0.05). The combination of SOY plus RE was greater than RE or SOY alone in reversing estrogen-deficiency-caused eNOS down-regulation (p ≤ 0.05).ConclusionsOur data suggest that the combinatory regimen of soy extract supplementation and regular RE training may be more beneficial to cardiovascular disease risk in a menopause rat model than either exercise or soy supplementation alone.
The purpose was to investigate the effects of CYP1A2 −163C > A polymorphism on the effects of acute caffeine (CAF) supplementation on anaerobic power in trained males. Sixteen trained males (age: 21.6 ± 7.1 years; height: 179.7 ± 5.6 cm; body mass: 72.15 ± 6.8 kg) participated in a randomized, double-blind, placebo (PLA) controlled crossover design. Participants supplemented with CAF (6 mg/kg of body mass) and an isovolumetric PLA (maltodextrin) in random order and separated by 7 days, before an all-out 30-s anaerobic cycling test to determine peak, average, and minimum power output, and fatigue index. Genomic deoxyribonucleic acid was extracted to identify each participants CYP1A2 genotype. Six participants expressed AA homozygote and 10 expressed C alleles. There was a treatment by genotype interaction for peak power output (p = .041, η2 = .265, observed power = 0.552) with only those expressing AA genotype showing improvement following CAF supplementation compared with PLA (CAF: 693 ± 108 watts vs. PLA: 655 ± 97 watts; p = .039), while no difference between treatments was noted in those expressing C alleles (CAF: 614 ± 92 watts vs. PLA: 659 ± 144 watts; p = .135). There were no other interaction or main effects for average or minimum power output, or fatigue index (p > .05). In conclusion, the ingestion of 6 mg/kg of CAF improved peak power output only in participants with the AA genotype compared with PLA; however, expression of the CYP1A2 did not influence average or minimum power output or fatigue index.
In order to study the effects of vitamin E and vitamin C supplementation on the bioenergetic index, 36 male physical education students were selected nonrandomly and assigned to a different supplementation protocol. The average age, weight, height, and fat percentage were 22.48 +/- 1.84 years, 64.93 +/- 7.84 kg, 175.4 +/- 5.66 cm, and 10.94 +/- 5.29%, respectively. The period of supplementation lasted 3 weeks. The subjects from group 1 consumed a daily dose of 400 mg of vitamin E, subjects from group 2 ingested 1000 mg of vitamin C, subjects from group 3 ingested 400 mg of vitamin E along with 1000 mg of vitamin C, and subjects from group 4 (control group) consumed a placebo. The tests applied were the running anaerobic sprint test (RAST) and the Cooper 12-min run test. The results indicate that there were no significant differences between groups during the study in anaerobic power assessed by RAST. We found a significant difference between group's, however, in aerobic power (p < 0.05). We concluded that daily consumption of vitamin E, vitamin C, and a combination of vitamin E and vitamin C for a period of 3 week significantly improved aerobic power.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.