Brad Schoenfeld is an internationally renowned expert on exercise and sports nutrition, and is a best-selling fitness author. He is based in New York.
Your current research is examining if high-rep sets increase lean muscle mass. What’s the latest?
I’m just finishing a study comparing the hypertrophic effects of 30-rep sets versus 10-reps sets in well-trained subjects. It’s too early to nail my colours to the mast because I am yet to do any statistical analysis, but I can say that it appears that higher-rep sets have a profound effect on hypertrophy, which is something I wasn’t expecting. I went into the study with the belief that lifting below 65% of the one-rep max for an exercise would have negligible effects on muscle growth, especially in experienced lifters.
What can you tell us about this work?
The study is comparing the effect of 30-rep sets against 10-rep sets for hypertrophy gains in well-trained subjects. Every other variable was standardised so both groups did the same total-body exercises, three sets in total, with the same tempo and rest protocols. What’s clear is that the 10-rep group are getting significantly stronger, while the 30-rep group are improving muscular endurance, which will not come as a surprise to anyone, but what is most interesting is the robust hypertrophy we think we are seeing in the endurance group.
Why do you think hypertrophy is occurring?
It’s too early to say for sure. I can’t provide a cause and effect theory yet, as we didn’t do a biopsy study, so I can only form a theoretical construction at present. One theory is that this group is recruiting more type-1 fibres. In the classical 6-12 rep range these fibres are never fully engaged and activated, because the type-2 fibres are reaching fatigue before that can happen. By doing longer-duration sets these slow-twitch fibres are being fully fatigued too, and that could be resulting in additional hypertrophy. Potentially only maximal hypertrophy occurs when your type-1 fibres are worked to the same capacity as your type-2 fibres, which would be an interesting development. There’s also the thought that the increased volume is a significant factor, which could add more weight to the importance of volume in hypertrophy.
Why is this potentially so significant?
Previous studies have examined the impact of higher-rep sets in untrained subjects, who have reported lean muscle mass gains, but this could be down to the simple fact that in untrained people, any form of resistance training should elicit hypertrophy. But to see potential muscle increases in experienced trainers could potentially be very significant. If the full analysis supports these preliminary findings then this could have profound repercussions for the future exploration of the best ways to build muscle quicker.
We may need to completely revisit programme design. I’m still cautious at this stage and we need hard evidence to flesh out this potential new paradigm. But it might turn out that it’s essential to use the entire rep continuum – from just single reps all the way up to 30-rep sets – to elicit maximal gains.
How can this new theory be incorporated into a training programme?
It could either be through adding some very high-rep sets at the end of your main workout as ‘finishers’; just doing these sets for single-joint moves; or using undulating rep protocols over different weeks as part of an overall periodisation plan. There could be endless permutations and it’s going to be fascinating to see where this road takes us in our approach and understanding of hypertrophy.
What else do people need to know about these sets?
Firstly, they really, really hurt! A lot of people picture high-rep sets as nice and easy with little pink dumbbells, but that’s far from the reality. It’s a lot easier to do a one-rep max than a 30-rep max because it lasts up to a minute and a half, rather than being over in seconds. These 30-rep sets are the most brutal ones you can do because subjects are working at their 30-rep max so the lactic acid build up is phenomenal. One thing I can say is that Schoenfeld was a dirty word during these sets!