This study was designed to evaluate recovery of dynamic muscle function following muscle fatigue produced by isokinetic testing. Sixteen physically active males (age = 29.2) performed fatigue and recovery tests on an isokinetic dynamometer (KINCOM 500H). The fatigue test involved concentric contractions of the quadriceps femoris performed until force output fell below 50% MVC for 3 consecutive contractions. This test was repeated 3 times, with 1 minute rest between sets. Recovery of force output was measured during the following 8 minutes. Following post hoc analysis, subjects were grouped into 1 of 3 groups based on their time to recovery of 80% MVC; Recovery immediately following fatigue exercise (Group 1), between 3 and 6 minutes (Group 2), or no recovery during the 8 minute period (Group 3). Analysis revealed a significant decline in peak force between bouts of a three-bout fatigue test for Groups 2 and 3 (p < 0.001), and no decline in Group 1. There was a significant relationship between decline in force output and time to recovery. Thus, subjects developing a greater amount of muscle fatigue took longer to recover following this isokinetic test. It was concluded that an isokinetic fatigue test to 50% MVC, repeated 3 times, is an appropriate fatigue generating protocol for most active males; that recovery time following isokinetic fatigue exercise varies among active males; and recovery may be directly related to decline in force output between bouts of a three-bout fatigue test.
- Muscle fatigue
ASJC Scopus subject areas
- Public Health, Environmental and Occupational Health
- Orthopedics and Sports Medicine
- Physical Therapy, Sports Therapy and Rehabilitation