Pilegaard H, Bangsbo J, Richter E A, Juel C
Copenhagen Muscle Research Centre, August Krogh Institute, University of Copenhagen, Denmark.
J Appl Physiol (1985). 1994 Oct;77(4):1858-62. doi: 10.1152/jappl.1994.77.4.1858.
The present study examined sarcolemmal lactate transport capacity in humans of widely different training status. Muscle biopsies were obtained from m. vastus lateralis in 39 subjects divided into untrained (n = 13), trained (n = 7), and athlete [sprint runners (n = 2), endurance runners (n = 5), triathletes (n = 3), and road (n = 6) and track (n = 3) bicyclists] groups. From the biopsy sample giant vesicles were produced with collagenase treatment to determine the sarcolemmal lactate transport capacity, and histochemical analyses were made. The athletes had a higher capacity to transport lactate than the untrained and trained subjects (P < 0.01). Within the group of athletes, the bicyclists had a higher lactate transport capacity than the runners (P < 0.05), whereas there was no difference among trained subjects, runners, and triathletes. The lactate transport capacity was related to the occurrence of type I muscle fibers (r = 0.48, P < 0.01). The present results suggest that the capacity to transport lactate is higher in athletes than in untrained and less trained subjects. It might indicate that lactate transport capacity in human skeletal muscle can be changed by a high volume of training including frequent high-intensity sessions. In addition, sarcolemmal lactate transport capacity appears to be related to the fiber type distribution of a muscle.
本研究检测了不同训练状态的人类肌膜乳酸转运能力。从39名受试者的股外侧肌获取肌肉活检样本，这些受试者被分为未训练组（n = 13）、训练组（n = 7）和运动员组[短跑运动员（n = 2）、耐力跑运动员（n = 5）、铁人三项运动员（n = 3）、公路自行车运动员（n = 6）和场地自行车运动员（n = 3）]。用胶原酶处理活检样本以制备巨大囊泡，从而测定肌膜乳酸转运能力，并进行组织化学分析。运动员转运乳酸的能力高于未训练和训练组受试者（P < 0.01）。在运动员组中，自行车运动员的乳酸转运能力高于跑步运动员（P < 0.05），而训练组受试者、跑步运动员和铁人三项运动员之间没有差异。乳酸转运能力与I型肌纤维的出现有关（r = 0.48，P < 0.01）。目前的结果表明，运动员转运乳酸的能力高于未训练和训练较少的受试者。这可能表明，通过大量训练，包括频繁的高强度训练课，人类骨骼肌中的乳酸转运能力可以发生改变。此外，肌膜乳酸转运能力似乎与肌肉的纤维类型分布有关。
