Abstract des Autors

The purpose of this study was to investigate the relationship between running economy (RE) and lower body flexibility. Thirty-four international-standard male distance runners (mean ± s, age 27 ± 5 years; body mass 64.9 ± 4.2 kg; VO2max 72.8 ± 3.7 ml/kg/min) gave written consent to participate in this study. The subjects performed an incremental treadmill test for the assessment of RE, lactate threshold and VO2max, and the sit-and-reach test was used to as-sess their general lower body and trunk flexibility. Running speeds below the lactate threshold were used to explore the relationship between running economy and sit-and-reach test performance. At 16.0 km/h, the VO2 was 50.6 ± 3.7 ml/kg/min (range: 44.2 to 57.1 ml/kg/min). Pearson product moment correlation coefficients revealed no significant relationships between aerobic demand at 16.0 km/h and age (r=-0.19), height (r=0.15), body mass (r=-0.18), or VO2max (r=-0.004). However, there was a highly significant relationship between aerobic demand at 16.0 km/h and the sit-and-reach test score (r=0.68; p<0.0001). These results suggest that the least flexible runners are also the most economical. It is possible that stiffer musculotendinous structures reduce the aerobic demand of submaximal running by facilitating a greater elastic energy return during the shortening phase of the stretch-shortening cycle. Verf.-Referat