Seasonal variability of maximal power of upper and lower limbs in ju-jitsu athletes

Background and Study Aim: An athlete's effectiveness during competitions is determined by the level of not only motor preparation, but also technical, tactical and psychological preparation. The aim of study was knowledge about putative seasonal differences in maximal power of upper and lower limbs in a group of male ju-jitsu athletes across 12 moths.
Material and Methods: Ju-jitsu practitioners of body mass from 67- to 100.1 kg and aged 22.4-25.6 years were subjected to the study. Assessment of their anaerobic power with the use of supramaximal (10s) legs cycling and arms cranking tests four times in a year. First examination was Cycling test was performed using MONARK ergometer, cranking test using the same type ergometer adopted to effort with upper limbs. The whole study has been undertaken in winter (January) and subsequent in spring (May), summer (July) and autumn (October). Log-transformed data were analysed using two-way (limb × season) analysis of variance ANOVA, followed by post-hoc the Tuckey`s test.
Result: The study did show well reproducibility of all the biomechanical factors of power and, thus, there were no significant differences between the four examinations. However, athletes showed slightly tendency of progressive improving their lower and upper power of limbs from test to test. In the 4th testing relative maximal lower limbs power was on average higher by 3% (11.44 Watt/BM) than that in the 1st one (11.09 Watt/BM), and for upper limbs the relevant progress accounted 5% (8.75 Watt/BM vs 8.33 Watt/BM). Time to peak power for lower limbs ranged from 3.04 to 6.09 seconds, and for upper limbs from 2.12-5.98 seconds. Time to peak power significantly depended on body mass, r = −0.332 for lower limbs, and r = −0.560 for upper limbs. As expected, power and work output were significant higher for legs cycling as compared to arm cranking at every examination. Moreover upper limbs showed higher susceptibility to fatigue as was expressed as co-called fatigue index. Given the mean value from four tests, fatigue index for were 11.15% and 15.92% for lower and upper limbs respectively.
Conclusions: Ju-jitsu athletes who regularly train throughout all the year exhibited lack of significant differences in performance of ultra-short, supramaximal efforts. The above refer both to upper and lower limbs. Slightly, non-significant improving of tests performance may be explained by better adaptation and higher motivation to these physical efforts. Subject of higher body mass and maximal absolute power can overcome wheel inertia faster and reach peak power earlier