Coetzer P, Noakes T D, Sanders B, Lambert M I, Bosch A N, Wiggins T, Dennis S C
Liberty Life Chair of Exercise and Sports Science, University of Cape Town Medical School, Observatory, South Africa.
J Appl Physiol (1985). 1993 Oct;75(4):1822-7. doi: 10.1152/jappl.1993.75.4.1822.
Black athletes currently dominate long-distance running events in South Africa. In an attempt to explain an apparently superior running ability of black South African athletes at distances > 3 km, we compared physiological measurements in the fastest 9 white and 11 black South African middle-to long-distance runners. Whereas both groups ran at a similar percentage of maximal O2 uptake (%VO2max) over 1.65-5 km, the %VO2max sustained by black athletes was greater than that of white athletes at distances > 5 km (P < 0.001). Although both groups had similar training volumes, black athletes reported that they completed more exercise at > 80% VO2max (36 +/- 18 vs. 14 +/- 7%: P < 0.005). When corrections were made for the black athletes' smaller body mass, their superior ability to sustain a high %VO2max could not be explained by any differences in VO2max, maximal ventilation, or submaximal running economy. Superior distance running performance of the black athletes was not due to a greater (+/- 50%) percentage of type I fibers but was associated with lower blood lactate concentrations during exercise. Time to fatigue during repetitive isometric muscle contractions was also longer in black runners (169 +/- 65 vs. 97 +/- 69 s; P < 0.05), but whether this observation explains the superior endurance or was due to the lower peak muscle strength (46.3 +/- 10.3 vs. 67.5 +/- 18.0 Nm/l lean thigh volume; P < 0.01) remains to be established.
目前在南非，黑人运动员在长跑项目中占据主导地位。为了解释南非黑人运动员在超过3公里的距离上明显更出色的跑步能力，我们比较了9名速度最快的南非白人中长跑运动员和11名黑人中长跑运动员的生理测量数据。在1.65至5公里的距离内，两组运动员的最大摄氧量百分比（%VO2max）相似，但在超过5公里的距离上，黑人运动员维持的%VO2max高于白人运动员（P < 0.001）。尽管两组的训练量相似，但黑人运动员报告称他们在超过80%VO2max强度下完成的训练更多（36 +/- 18% 对 14 +/- 7%：P < 0.005）。在对黑人运动员较小的体重进行校正后，他们维持高%VO2max的卓越能力无法通过最大摄氧量、最大通气量或次最大跑步经济性的任何差异来解释。黑人运动员卓越的长跑表现并非归因于更高比例（约50%）的I型纤维，而是与运动期间较低的血乳酸浓度有关。黑人跑步者在重复性等长肌肉收缩中的疲劳时间也更长（169 +/- 65秒对97 +/- 69秒；P < 0.05），但这一观察结果是解释了卓越的耐力，还是由于较低的肌肉峰值力量（46.3 +/- 10.3对67.5 +/- 18.0牛米/瘦大腿体积；P < 0.01），仍有待确定。
