I’ve been poking around the research literature and have a question about programming for hypertrophy.
Schoenfeld, in “The Mechanism of Muscle Hypertrophy and Their Application to Resistance Training,” writes that there are three primary ways that resistance training causes hypertrophy: mechanical tension, muscle damage, and metabolic stress. The conventional wisdom is that doing some amount of high-rep work is necessary to optimize hypertrophy, because high rep sets cause a great deal of metabolic stress and fatigue the greatest number of muscle fibers. Broadly, my question is whether this is correct. Could we instead just do a large number of (for example) triples to accumulate the same total volume, and hopefully the same hypertrophic response?
The most relevant study I found was “Effects of different volume-equated resistance training loading strategies on muscular adaptions in well-trained men,” by Schoenfeld et al. Volume-equated 7x3 and 3x10 rep schemes were compared, and the growth of the biceps was found to be identical. Lyle McDonald writes that the growth of the quadriceps was also measured and found to be the same between groups, but the data was too low quality to include in the final paper. The paper notes some practical issues with doing that many heavy triples – it took a long time, people got injured, motivation to train was low – but some of them could be mitigated by just doing more triples at lower intensity (on shorter rest periods, if time is a concern).
Further, in “Greater Gains in Strength and Power with Intraset Rest Intervals in Hypertrophy Training,” one group did 4 sets of 10 with 120 second rests, and the other did 8 sets of 5 with 60 second rests. Hypertrophy was the same, and the group that broke the volume into smaller sets actually got stronger.
I don’t want to turn this post into a lengthy literature review, but let me mention one more piece of evidence. If metabolic stress were important above and beyond just total volume done, we might expect bodybuilding-style “metabolite” training techniques, such as occlusion training, drop sets, and rest-pause, to produce superior hypertrophy. But my reading of the literature is that they don’t.
So, setting practical concerns like time efficiency aside, is there any reason at all to bother with high rep sets (say 8s and 10s) for hypertrophy? Do I lose anything at all by splitting a planned set of 10 into two sets of 5 with short rests? I know very little about physiology, so I was hoping you could point out reasons this might be a bad idea that I’m missing.
Thanks,
Patrick