Itoh H, Ohkuwa T, Yamazaki Y, Miyamura M
Department of Physical Education, Nagoya Institute of Technology, Japan.
Nagoya J Med Sci. 1996 Dec;59(3-4):135-42.
The purposes of this study were 1) to confirm whether there is a difference in the levels of blood lactate and ammonia after supramaximal uphill and downhill running for the same short duration and 2) to examine the relationship between peak blood lactate levels and work/lean body mass (LBM), as well as the relationship between peak blood ammonia levels and work/LBM following supramaximal uphill and downhill running. Eight healthy, untrained male subjects performed supramaximal uphill and downhill running on a motor-driven treadmill for about 70 sec. Though there was a significant difference (p < 0.05) in running speed and work/LBM between supramaximal uphill and downhill running, no significant difference was found in exhaustion time or heart rate. Both the peak blood lactate and ammonia concentrations were significantly lower after downhill running than after uphill running (p < 0.05). Although there was no significant relationship between peak blood ammonia levels and work/LBM following either uphill or downhill running, significant linear relationships between the peak blood lactate levels and work/LBM were observed following uphill running (r = 0.74, p < 0.05) and downhill running (r = 0.72, p < 0.05). These results suggest that the differences in the blood lactate and ammonia concentration between supramaximal downhill and uphill running of the same duration may be due to the total recruitable muscle mass during exercise, and that peak blood lactate can be used as an index of anaerobic work capacity for untrained subjects under these running conditions.
1）确认在相同短时间内进行超最大强度上坡和下坡跑后，血乳酸和血氨水平是否存在差异；2）研究超最大强度上坡和下坡跑后，血乳酸峰值水平与工作/去脂体重（LBM）之间的关系，以及血氨峰值水平与工作/LBM之间的关系。八名健康的未经训练的男性受试者在电动跑步机上进行了约70秒的超最大强度上坡和下坡跑。尽管超最大强度上坡跑和下坡跑之间的跑步速度和工作/LBM存在显著差异（p < 0.05），但在疲劳时间或心率方面未发现显著差异。下坡跑后的血乳酸和血氨峰值浓度均显著低于上坡跑后（p < 0.05）。尽管在上坡跑或下坡跑后，血氨峰值水平与工作/LBM之间均无显著关系，但在上坡跑（r = 0.74，p < 0.05）和下坡跑（r = 图0.72，p < 0.05）后，观察到血乳酸峰值水平与工作/LBM之间存在显著的线性关系。这些结果表明，相同持续时间的超最大强度下坡跑和上坡跑之间血乳酸和血氨浓度的差异可能归因于运动过程中可募集的总肌肉量，并且在这些跑步条件下，血乳酸峰值可作为未经训练受试者无氧工作能力的指标。
