Jakeman P
School of Sport and Exercise Sciences, University of Birmingham, UK.
Br J Sports Med. 1993 Sep;27(3):157-61. doi: 10.1136/bjsm.27.3.157.
An élite athlete engaged in a longitudinal programme of physiological assessment suffered a loss of performance that was later ascribed to an asymptomatic viral illness. In this 15-month, single subject, repeated measures study it was possible to demonstrate a severe decrease of exercise performance following viral illness. The oxygen uptake equivalent to the onset of blood lactate accumulation of 4 mmol l-1 (OBLA) decreased by 17% following viral illness, then recovered slowly, but had not returned to pre-viral levels 50 weeks later. Steady state exercise metabolism was also affected. During prolonged exercise at 70% of VO2max the proportion of energy derived from carbohydrate metabolism increased and an inability to maintain euglycaemia was observed. In both the graded and prolonged exercise tests, a pronounced tachycardia was evident after viral illness, possibly as a result of a febrile response to the infection, or, a direct effect of the virus upon myocardial performance. These data provide some preliminary and unique findings of the effects of viral illness upon the physiological and metabolic responses to exercise in an élite athlete. The data also demonstrate the sensitivity of currently used laboratory measures of exercise performance to monitor the changes in physiological function during recovery from viral illness.
一名参与长期生理评估项目的精英运动员出现了成绩下滑，后来发现这是由一种无症状病毒性疾病所致。在这项为期15个月的单受试者重复测量研究中，得以证实病毒性疾病后运动成绩严重下降。病毒感染后，相当于血乳酸积累起始浓度4 mmol l-1时的摄氧量（OBLA）下降了17%，随后缓慢恢复，但在50周后仍未恢复到病毒感染前的水平。稳态运动代谢也受到了影响。在以70%的最大摄氧量进行长时间运动时，碳水化合物代谢所提供能量的比例增加，并且观察到无法维持正常血糖水平。在分级运动测试和长时间运动测试中，病毒感染后均出现明显的心动过速，这可能是对感染的发热反应所致，或者是病毒对心肌功能的直接影响。这些数据提供了一些关于病毒性疾病对精英运动员运动生理和代谢反应影响的初步且独特的发现。这些数据还证明了目前用于监测运动成绩的实验室测量方法在监测病毒性疾病恢复过程中生理功能变化方面的敏感性。
