Available at: http://digitalcommons.calpoly.edu/theses/1109
Date of Award
MS in Kinesiology
Kellie Green Hall
The primary purpose of this study was to examine whether variability of practice enhances neuromuscular adaptations when compared to traditional strength training. The secondary purpose was to investigate whether there was a difference in perception of exertion between the two strength programs. Forty one subjects (23 women and 18 men) were assigned to either the control group or one of two treatment groups by a blocked-random method. Subject's one repetition maximum (1RM) for the kettlebell press and leg press were measured at baseline, after 4 weeks of training, and after 8 weeks of training. The treatment groups completed 8 weeks of training consisting of 3 days a week with at least one recovery day in between each session. In weeks 1 through 3, subjects undergoing the traditional treatment completed 3 sets of 8 repetitions at 70% of their 1RM for each exercise. Weeks 4 through 6 were composed of 3 sets of 6 repetitions at 77% 1RM. In weeks 7 and 8, 3 sets of 4 repetitions at 85% 1RM were performed. Over the course of the eight weeks, the variable treatment was comprised of 5 sets of the kettlebell and leg press. A set of 4 repetitions at 77% of the subject's 1RM, one of 5 repetitions at 70% 1RM, another of 3 repetitions at 85% 1RM, one of 6 repetitions at 65% 1RM, and finally a set of 2 repetitions at 93% 1RM were performed every session. The order of these sets were changed every 3 weeks, altering where in the session the highest intensity set was in relation to the lower intensity sets. Ratings of perceived exertion (RPE) were recorded following treatment to determine subject's perception of intensity during each set. Analysis of variance with repeated measures did not reveal significantly different strength gains between treatment groups in either lift, although variable treatment resulted in greater mean strength gains over almost every time interval. Analyses of RPE data revealed significantly lower reported RPE values for the variable treatment compared to the traditional treatment in both lifts. The greater mean strength gains and significantly lower RPEs of the variable treatment program compel us to conclude it is a superior training method for increasing strength compared to the traditional program.