Exercise Metabolism
Masoud Rahnama; Hamid Mohebi; Hamid Rajabi
Abstract
Purpose: The aim of this study was to compare the metabolic profile of elite male karate athletes based on their physical fitness level during different phases of six competitions in one day, similar to real karate competitions.Study method: Ten young elite karateka participated in this research. Based ...
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Purpose: The aim of this study was to compare the metabolic profile of elite male karate athletes based on their physical fitness level during different phases of six competitions in one day, similar to real karate competitions.Study method: Ten young elite karateka participated in this research. Based on the Z scores obtained from physical fitness tests, including aerobic power (Bruce test), anaerobic power (30 s Wingate test), vertical jump, 30 m sprint, and agility (9×4 m), they were divided into two groups of high (n=5) and low (n=5) physical fitness. Each karateka performed six simulated committee competitions with the same rest interval as official tournaments and according to the rules of the World Federation. Venous blood samples were collected before and after the first and sixth competition. Repeated measures ANOVA was used to investigate differences at p<0.05.Results: Decreases in pH (p<0.001), increases in tryptophan (p=0.034), lactate (p<0.001), and malondialdehyde (p=0.007), and changes in glucose (p=0.003) were significant in total measured time points. Moreover, by examining time×group interaction, a significant difference was observed between the groups in plasma lactate (p=0.014), so that it was significantly higher after the sixth competition in the low physical fitness group than the other group (5 ± 0.1 vs. 3.9 ± 0.2 mmol/L, p=0.002).Conclusion: Karate athletes with low physical fitness seem to provide a larger portion of ATP needed during the sixth competition than the first competition from the anaerobic glycolysis pathway and by consuming extracellular carbohydrate sources such as plasma glucose.
Elham Motamedi; Maryam Ebrahimi; Abuzar Jorbonian
Abstract
Background: This study aimed to investigate the effect of caffeine and carbohydrate co-ingestion on anaerobic performance and muscular strength of female wushu athletes. Methods: 7 female wushu athletes with 22.00 ± 6.11 years of age, 52.96 ± 4.87 kg weight and 161.29 ± 5.28 cm height ...
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Background: This study aimed to investigate the effect of caffeine and carbohydrate co-ingestion on anaerobic performance and muscular strength of female wushu athletes. Methods: 7 female wushu athletes with 22.00 ± 6.11 years of age, 52.96 ± 4.87 kg weight and 161.29 ± 5.28 cm height participated in 1RM leg and bench press and RAST tests on 4 occasions separated by 1-week washout after accidental consumption of caffeine (6 mg/kg in 250 mL water), 8% carbohydrate (21 g in 250 mL water), caffeine+carbohydrate and placebo. Data were analyzed by repeated measure ANOVA and Bonferroni tests in SPSS26, α = 0.05).Results: caffeine alone did not affect variables (P ≥ 0.05). Carbohydrate consumption increased 1RM bench press ⁓7% (P = 0.010) and 1RM leg press ⁓16% (P = 0.033). co-ingestion of carbohydrate and caffeine improved mean power ⁓15% (P = 0.027), 1RM bench press ⁓26% (P = 0.005) and leg press ⁓39% (P = 0.027). Conclusion: it seems, that carbohydrate has more effect on strength than caffeine, but combined with caffeine it may improve mean power besides the muscular strength in female wushu athletes due to effects on the central nervous system and increasing carbohydrate effect.
