Comparison of 1 Day and 3 Days Per Week of Equal-Volume Resistance Training in Experienced Subjects

Abstract
There is not a strong research basis for current views of the importance of individual training variables in strength training protocol design. This study compared 1 day versus 3 days of resistance training per week in recreational weight trainers with the training volume held constant between the treatments. Subjects were randomly assigned to 1 of 2 groups: 1 day per week of 3 sets to failure (1DAY) or 3 days per week of 1 set to failure (3DAY). Relative intensity (percent of initial 1 repetition maximum [1RM]) was varied throughout the study in both groups by using a periodized repetition range of 3–10. Volume (repetitions × mass) did not differ (p ≤ 0.05) between the groups over the 12 weeks. The 1RMs of various upper-and lower-body exercises were assessed at baseline and at weeks 6 and 12. The 1RMs increased (p ≤ 0.05) significantly for the combined groups over time. The 1DAY group achieved ∼62% of the 1RM increases observed in the 3DAY group in both upper-body and lower-body lifts. Larger increases in lean body mass were apparent in the 3DAY group. The findings suggest that a higher frequency of resistance training, even when volume is held constant, produces superior gains in 1RM. However, training only 1 day per week was an effective means of increasing strength, even in experienced recreational weight trainers. From a dose-response perspective, with the total volume of exercise held constant, spreading the training frequency to 3 doses per week produced superior results.