Gleeson M, Blannin A K, Walsh N P, Field C N, Pritchard J C
School of Sport and Exercise Sciences, University of Birmingham, UK.
Eur J Appl Physiol Occup Physiol. 1998 Feb;77(3):292-5. doi: 10.1007/s004210050336.
Eccentric muscle actions are known to induce temporary muscle damage, delayed onset muscle soreness (DOMS) and muscle weakness that may persist for several days. The purpose of the present study was to determine whether DOMS-inducing exercise affects blood lactate responses to subsequent incremental dynamic exercise. Physiological and metabolic responses to a standardised incremental exercise task were measured two days after the performance of an eccentric exercise bout or in a control (no prior exercise) condition. Ten healthy recreationally active subjects (9 male, 1 female), aged 20 (SD 1) years performed repeated eccentric muscle actions during 40 min of bench stepping (knee high step; 15 steps x min[-1]). Two days after the eccentric exercise, while the subjects experienced DOMS, they cycled on a basket loaded cycle ergometer at a starting work rate of 150 W, with increments of 50 W every 2 min until fatigue. The order of the preceding treatments (eccentric exercise or control) was randomised and the treatments were carried out 2 weeks apart. Two days after the eccentric exercise, all subjects reported leg muscle soreness and exhibited elevated levels of plasma creatine kinase activity (P < 0.05). Endurance time and peak VO2 during cycling were unaffected by the prior eccentric exercise. Minute volume, respiratory exchange ratio and heart rate responses were similar but venous blood lactate concentration was higher (P < 0.05) during cycling after eccentric exercise compared with the control condition. Peak blood lactate concentration, observed at 2 min post-exercise was also higher [12.6 (SD 1.4) vs 10.9 SD (1.3) mM; P < 0.01]. The higher blood lactate concentration during cycling exercise after prior eccentric exercise may be attributable to an increased rate of glycogenolysis possibly arising from an increased recruitment of Type II muscle fibres. It follows that determination of lactate thresholds for the purpose of fitness assessment in subjects experiencing DOMS is not appropriate.
已知离心性肌肉动作会引发暂时性肌肉损伤、延迟性肌肉酸痛（DOMS）以及可能持续数天的肌肉无力。本研究的目的是确定诱发DOMS的运动是否会影响后续递增动态运动时的血乳酸反应。在进行一次离心运动 bout 后两天或在对照（无先前运动）条件下，测量对标准化递增运动任务的生理和代谢反应。十名年龄为20（标准差1）岁的健康休闲活跃受试者（9名男性，1名女性）在40分钟的台阶试验（高抬腿；每分钟15步）期间进行重复的离心性肌肉动作。离心运动后两天，当受试者经历DOMS时，他们在装有篮子的自行车测力计上以150W的起始工作速率骑行，每2分钟增加50W直至疲劳。先前治疗（离心运动或对照）的顺序是随机的，且治疗相隔2周进行。离心运动后两天，所有受试者均报告腿部肌肉酸痛且血浆肌酸激酶活性水平升高（P < 0.05）。骑行期间的耐力时间和峰值VO2不受先前离心运动的影响。每分通气量、呼吸交换率和心率反应相似，但与对照条件相比，离心运动后骑行期间静脉血乳酸浓度更高（P < 0.05）。运动后2分钟2分钟时观察到的血乳酸峰值浓度也更高[12.6（标准差1.4）对10.9标准差（1.3）mM；P < 0.01]。先前离心运动后骑行运动期间较高的血乳酸浓度可能归因于糖原分解速率增加，这可能是由于II型肌纤维募集增加所致。因此，在经历DOMS的受试者中为健康评估目的确定乳酸阈值是不合适的。
