摘要:

The purpose of this study was to compare the effects of recovery type (active vs. passive) on the time spent atmax and above 90% ofmax during short intermittent runs (15 s) at 120% of maximal aerobic speed. Twelve male subjects peiformed a graded test and intermittent runs (15 s) alternated with 15 s of active recovery (50% of maximal aerobic speed) or with 15 s of passive recovery to exhaustion. The time to exhaustion during the intermittent runs with active recovery (445 ± 79 s) was significantly shorter (p < 0. 001) compared with passive recovery (745 ± 171 s). No significant difference wasfound between time spent atmax and above 90% ofmax for intermittent runs alternated with active recovery (180 ± 121 s and 282 ± 1 17 s, respectively) and intermittent runs alternated with passive recovery (191 ± 135 s and 317 ± 132 s, respectively). The times spent atmax (p < 0.05) and above 90% ofmax (p < 0.00 1), expressed in percentage of time to exhaustion, were significantly longer for intermittent runs alternated with active recovery (41 ± 27% and 64 ± 24%, respectively) than with passive recovery (25 ± 16% and 43 ± 1 6%, respectively). In conclusion, the present study has shown that the time to exhaustion during repeated highintensity exercise was significantly greater for passive compared with active recovery, despite no difference in absolute time spent at a high percentage ofmax. However, the time spent at a high percentage ofmax, expressed as a percentage of time to exhaustion, was significantly higher for active compared with passive

ISSN:1066-7814    

DOI:h2004-054

出版商:NRC Research Press    

年代:2004

数据来源: NRC

摘要:

The aim of this study was to analyse the variations of the metabolic and technical parameters during a maximal 400-m freestyle event. Seven trained male swimmers swam a maximal 400-m freestyle as if in competition (255.8 ± 6.9 s). Intermediate time and stroke rate (SR) were recorded at each length (25 m). To estimate the changes in metabolic parameters during the 400-m event, they swam a 300-, 200-, and 100-m test set from each length of the 400-m event results, resting 90 min between each test. The exact speed at each length was given with a visual light pacer. Oxygen uptake () and blood lactate concentration ([Lac]) were measured before and immediately after each test.and [Lac] were stable during the 100-, 200-, and 300-m test but significantly higher (p < 0.05) during 400-m test. The estimated contribution of anaerobic metabolism (EsCANA) during the first 100-m and the 400-m represented 45% and 20% of total energy output, respectively. Speed decreased significantly (p < 0.05) after the first 100-m and remained stable until the end. SR decreased significantly after the first 100-m, then increased until the end, while stroke length (SL) decreased linearly throughout the 400-m. During the first or the last 100-m, ESCANAwas not correlated with the changes in V, SR, or SL between the second and the first 100-m, and between the fourth and the third 100-m, respectively. To conclude, this study showed that the swimmers were not able to maintain stable SL during the 400-m event. Thus, to sustain stable velocity and to compensate for the decrease in SL, swimmers increased SR throughout the last 300-m

ISSN:1066-7814    

DOI:h2004-055

出版商:NRC Research Press    

年代:2004

数据来源: NRC

ISSN:1066-7814    

DOI:h2004-056

出版商:NRC Research Press    

年代:2004

数据来源: NRC