The purpose of this study was to determine whether twitch contractile properties and strength of the triceps surae could be altered by 8 weeks of low-repetition or high-repetition isotonic exercise. Subjects were randomly assigned to either the low- or high-repetition group. Before- and after-training measurements were recorded for strength and contractile properties. The contractile variables of the muscle twitch were latency, time to peak force, peak force, half-contraction time, and half-relaxation time. Strength measurements were determined utilizing a one repetition maximal (1-RM) heel-raise testing device. A two-way ANOVA with repeated measures was used to test the effect of training on each variable. Both groups showed a significant increase in 1-RM and half-relaxation time and a decrease in electrical stimulation current after the 8-week training period. It was concluded that if high-repetition exercises develop slow-twitch Type I muscle fibers and low-repetition exercises develop fast-twitch Type II fibers, training programs must be designed specifically according to the desired outcome.
Crayton L. Moss and Scott Grimmer
Crayton L. Moss, Beatrice Gorton and Suzanne Deters
The purpose of this study was to compare the effects of four different treatments on the control of the amount and rate of foot pronation while running. The four treatments were the reverse 8-stirrup taping technique, the low-dye taping technique, prescribed rigid orthotic devices, and no support in the running shoe. Six intercollegiate cross-country runners were filmed from the rear while running on a treadmill, and the film data were analyzed. A two-way MANOVA indicated no significant overall treatment effect for the dependent variables. A one-way ANOVA indicated that the reverse 8-stirrup taping technique significantly reduced the amount of maximum pronation when compared to shoes-no support and low-dye taping techniques. The reverse 8-stirrup also had significantly fewer degrees of total rear foot movement when compared to the low-dye taping technique. No other significant comparisons were realized. It was concluded that the reverse 8-stirrup would be as effective a treatment for excessive pronation in runners as the prescribed rigid orthotic device.