Relationships of Muscular Endurance Among Specific Muscle Groups for Continuous and Intermittent Static Contractions

Abstract

The static contraction endurance characteristics of five muscle groups, finger flexors, forearm extensors, forearm flexors, plantar flexors, and dorsal flexors were investigated in a group of normal, healthy college-aged men (N = 38). Two maximal contraction endurance tasks, continuous and intermittent contraction (3 s contraction, 3 s rest), each totaling 63 s of contraction were investigated. The following four parameters were examined: maximal force production (strength), maximal force output summated (TW), percent total force output (%TW), and percent final contraction (%FC). The first two reflect the raw force production capabilities of the muscle groups both for an instance of peak achievement and over time (Impulse). The latter two reflect endurance capacity with strength taken into account.

Analysis of the endurance data produced the following conclusions: (a) continuous contraction resulted in significantly greater fatigue than did intermittent contraction, (b) endurance was specific to the muscle group, (c) endurance was specific to the task being performed, and (d) the fatigue curves were effectively described by single and double component polynomial regression curves. These results support the contention that endurance is unique to each muscle group as well as specific to the task performed.

Key Words:

• muscle endurance
• relative endurance
• absolute endurance
• strength
• polynomial regression
• factor analysis