Physiological and psychological indices of fatigue during static contractions
- 1 January 1983
- journal article
- research article
- Published by Springer Science and Business Media LLC in European Journal of Applied Physiology
- Vol. 50 (2), 179-193
- https://doi.org/10.1007/bf00422157
Abstract
The development of fatigue and the relationship between psychological and physiological indices of fatigue were studied in a group of 18 male subjects during static contractions. Exercise was performed as a static elbow flexion at 25% MVC. Heart rate (HR), intraarterial blood pressure (BP) and surface EMG [mean amplitude (MA) and central frequency (CF)] were studied during contractions sustained until exhaustion. The amount of effort expended (relative to total exhaustion) and the rating of perceived pain were recorded following contractions interrupted after 20, 30 ⋯ 80, and 100% of endurance time. HR, BP and EMG amplitude responses were similar to those previously recorded. The decline in CF occurred in two phases, possibly related to a change in motor unit recruitment after the initial 70% of endurance time. The subjects overestimated the amount of effort expended and thus underestimated their endurance capacity. The best correlation between perceived effort and physiological responses was obtained using blood pressure data, whereas changes in EMG data did not parallell the psychological responses. It is concluded that the perception of effort during a static contraction is produced through a complex process, in which several influences of peripheral and central origin are integrated.Keywords
This publication has 22 references indexed in Scilit:
- Circulatory response to static muscle contractions in three different muscle groupsClinical Physiology and Functional Imaging, 1981
- The perception of effort: An inductive approachEuropean Journal of Applied Physiology, 1979
- Magnitude Perception of Added Inspiratory Resistance During Steady-State ExerciseErgonomics, 1978
- An electromyographic index for localized muscle fatigueJournal of Applied Physiology, 1977
- Effort of Dynamic Exercise: Influence of Load, Duration, and TaskErgonomics, 1977
- Firing rate and recruitment order of toe extensor motor units in different modes of voluntary conraction.The Journal of Physiology, 1977
- Perceived Exertion, Heart Rate, Oxygen Uptake and Blood Lactate in Different Work OperationsErgonomics, 1972
- Effort in isometric muscular contractions related to force level and durationPerception & Psychophysics, 1970
- EXERCISE PERFORMANCE AND PERCEIVED EXERTION IN PATIENTS WITH CORONARY INSUFFICIENCY, ARTERIAL HYPERTENSION AND VASOREGULATORY ASTHENIA1Acta Medica Scandinavica, 1970
- Subjective scale of force for a large muscle group.Journal of Experimental Psychology, 1962