Observations on Frequency and Intensity of Isometric Muscular Effort in Developing Static Muscular Strength in Post-Pubescent Males

The purpose of this study was to compare the effectiveness of a single daily six-second exercise bout using two-thirds maximum tension with an exercise program involving more frequent exercise bouts at 80 per cent maximum tension. Thirty post-pubescent boys divided into two experimental groups and one control group served as subjects. Each experimental group was given a four weeks' training program restricted to isometric exercise of the wrist, the programs differing only in regard to the frequency of the exercise bouts and the levels of static muscular tension employed. The results generally supported the findings of Hettinger and Muller, in that brief periods of isometric tension (one six-second bout daily at two-thirds maximum tension) proved to be as effective for strength development as more frequently repeated exercise bouts at higher levels of tension. However, the latter method was found to be somewhat superior in terms of strength retention.