Effects of 4, 8, and 12 Repetition Maximum Resistance Training Protocols on Muscle Volume and Strength.
Kubo, Keitaro; Ikebukuro, Toshihiro; Yata, Hideaki
To determine skeletal muscle adaptations (strength and hypertrophy) in response to volume-equated resistance training with divergent repetition strategies.
10 weeks at 2 training sessions per week:
Group 1: high load @ 7 sets x 4 reps.
Group 2: intermediate load @ 4 sets x 8 reps.
Group 3: Low load @ 3 sets x 12 reps.
Group 4: Non-exercising control group.
The increase in muscle size was similar among the 3 training protocols when the training volume was equated, whereas the increase in muscle strength was lower with the 3 x 12 protocol compared to the other two.
IN PLAIN ENGLISH:
A lot of protocols work for increasing muscle size (7 x 4, 4 x 8, and 3 x 12), while the 3 x 12 did not increase muscle strength as much as the other two. To demonstrate pure strength, heavier resistance that recruits a larger quantity of muscle fibers allows for that, thus the 7 x 4 and 4 x 8 were effective. The 3 x 12 required a lighter resistances thus the recruitment of fewer fibers occurred and did not result in optimal strength increase.