Abstract

Proper manipulation of volume, intensity, and frequency are some of the key components of designing a strength training program. A lot of research is available related to increases in strength based on training; however, much less is known about the magnitude of strength gains based on the volume, intensity, and frequency of training. Rhea et al. use the analogy of trying to identify a dose-response relationship between the amount of a prescribed drug and the effect on an illness or disease. This would facilitate the proper (and most effective) dose of a medication for the specific individual. The proper dose-response relationship in the design of strength training programs can assist in the prevention of overstress injuries (overprescription) or failure to achieve improvement (underprescription). This specific study was a meta-analysis of 140 other studies with a total of 1,433 effect sizes to identify the dose-response relationship. Both published and unpublished studies that included strength measurements before and after strength training interventions were reviewed. Each of these studies was coded for the following variables: descriptive information, including gender and age; frequency of training; mean training intensity; number of sets performed; and training status of the participants. The variables of training were defined as follows: 1. Intensity: average percent of 1 repetition maximum (1 RM). 2. Frequency: number of days per week that participants trained a particular muscle group. 3. Volume: number of sets performed (per muscle group) during each workout. The training status of each participant was divided into trained and untrained classifications. A significant effect size difference was found between trained and untrained participants with no difference between male and female effect sizes. Training status was the only variable to affect the dose-response curves. In untrained participants, training with a mean intensity of 60% of 1 RM (4 sets) 3 days per week elicited maximal gains. In trained participants, training at 80% of 1RM (4 sets) 2 days per week elicited maximal gains. The findings show the importance of progression and progressive overload. The initial standard of 1 set of 8-12 repetitions still seems appropriate; however. individuals desiring continued gains in muscular fitness must progress to higher volumes and intensities to avoid plateaus in adaptations. Textauszug