Abstract

As suggested by Harre and Leopold (1987), in speed endurance and short middle distance events, strength endurance is the speed strength support for there cyclic movements and therefore is a determinant of the competitive performance. Nummela et al. (1992) have studied the effects of fatigue on sprinters performing a 400 m race. To evaluate the strength level decrease, the subjects performed a drop jump test (from 39 cm height) after the end of each of the referred distances. Moreover, the authors found a linear negative relationship between jump height and lactate levels above 6mmol/l. The aim of the study was to identify the influence of anaerobic lactic exercise on power and strength parameters change of 400 m runners. The subjects were 400 m runners (n=8; height 181 ± 4.6 cm; body mass 72.2 ± 4.4 kg). The study was carried out in indoor track and field arena (lap length 200 m) on January 10, 2011, during the Lithuanian university track and field championship. Subjects performed stretching exercise and participated in vertical and drop jumps (3 jumps, rest interval 1 min). After jumps participants performed warm up and then repeated vertical and drop jumps. After jump tests subjects participated in competition (400 m race, anaerobic lactated exercise). At the end of the 400 m race (after 3 min rest) subjects repeated vertical and drop jumps. During the competition there was used fully automated finishing system, which automatically turns on by the starter’s signal (shot) and automatically records the finish time. This finish system is certified by the IAAF. The running surface in indoor track and field was Regupol AG. Results: comparing the values of 400 m runners results of the first and the last 200 meters we found statistically significant difference (2.09 s) (p<0.05). The heights of vertical jump test after 400 m race were significantly reduced (p<0.05). After anaerobic lactated exercise (400 m race) there was significant reduce in power parameters (the height of drop jump test decreased by 33.66 9.88%). Thus we may conclude that anaerobic lactic exercise has the biggest influence on power parameters: the height of drop jump test decreased 33.66 ± 9.88%. Strength parameters (the height of the vertical jump) significantly decreased after 400 meters running (p<0.05). Verf.-Referat