Byström S
Division of Applied Work Physiology, National Institute of Occupational Health Solna, Sweden.
Ups J Med Sci. 1994;99(1):51-62. doi: 10.3109/03009739409179350.
The aim was to evaluate the energy turnover in the forearm during isometric submaximal exercise. Eight subjects performed isometric handgrip contractions until exhaustion at 10%, 25% and 40% of maximal voluntary contraction (MVC). Blood samples were drawn frequently from the cubital vein of the exercising arm during exercise and a 60 minutes recovery period, and forearm blood flow (plethysmography) was monitored during the same periods. Oxygen uptake and lactate release were used to quantify aerobic and anaerobic energy expenditure. Electromyography (frequency analysis) was monitored during exercise. Anaerobic glycolysis contributed 4%, 31% and 37% of the ATP production in the three experiments, respectively, but total ATP production from anaerobic glycolysis was the same, suggesting a maximal anaerobic glycolytic capacity (MAGC). MAGC may be a limiting factor for muscle performance at 25 and 40% MVC, but not at 10% MVC. Judging from the match between oxygen debt or estimated oxygen deficit vs the anaerobic energy production, the muscles recovered during 60 min rest after 10% MVC and 40% MVC. However, recovery after 25% MVC may have been incomplete.
目的是评估等长次最大运动期间前臂的能量转换。八名受试者进行等长握力收缩，直至达到最大自主收缩（MVC）的10%、25%和40%时力竭。在运动期间以及60分钟的恢复期内，频繁地从运动手臂的肘静脉采集血样，并在同一时期监测前臂血流量（体积描记法）。摄氧量和乳酸释放量用于量化有氧和无氧能量消耗。运动期间监测肌电图（频率分析）。在这三个实验中，无氧糖酵解分别占ATP产生量的4%、31%和37%，但无氧糖酵解产生的总ATP量相同，这表明存在最大无氧糖酵解能力（MAGC）。MAGC可能是25%和40%MVC时肌肉性能的限制因素，但在10%MVC时不是。从氧债或估计的氧亏空与无氧能量产生之间的匹配情况判断，10%MVC和40%MVC后，肌肉在60分钟休息期内恢复。然而，25%MVC后的恢复可能不完全。
