TRAINING IN HUMAN MUSCLES WORKING WITH AND WITHOUT BLOOD SUPPLY

Abstract

A weight ergograph adapted for the measurement of the work of human extensor digitorum communis muscle is descr. The muscles were voluntarily worked to fatigue once each day. The right arm was worked without blood supply, the left with blood supply. Training patterns without blood supply showed very small and slow gains in total work done amounting to an increase of, at most, 30% in 16 mos. The work ability of muscle working without blood supply was not significantly increased by effective training with blood supply. The time of onset of ischemic pain was delayed only very slowly by daily work without blood supply. The intensity of ischemic pain was markedly reduced in the process. An interim of daily work with blood supply re-intensified the ischemic pain on later trials without blood supply. The training pattern of muscles working with blood supply showed rapid assumption of steady state ability with light load. Shifting to a load 300 g. heavier resulted in a long period of static work capacity with finally a rapid increase in work ability. The addition of another 300 g. abolished all signs of training for 9 mos. Yet, a daily exercise period of 15 mins. with lighter load served to increase the work capacity with the heavier load. The anaerobic energy release mechanism in muscle evidently undergoes little change as a result of training. Training is thus largely a phenomenon of improvement in nervous direction and vascular supply.