Contrary to a lot of the training advice out there, you can and will gain muscle using higher reps.
The classic 20-rep squat routine has been helping guys add mass to their legs since the 1930’s, when Mark Berry, Joseph Hise and Peary Rader first wrote about it.
It was still working in the 1980′s when Randall J. Strossen wrote about it in Super Squats.
And modern research is confirming what many of the early Iron Game pioneers discovered for themselves through trial and error.
A good example comes from a recent study comparing the effect of high and low reps on muscle growth. Subjects in the study trained their legs on the leg extension machine 3 times a week for 10 weeks, using one of three different set and rep configurations:
- 1 set of 10-12 reps (80% 1-RM) performed to voluntary failure (80%-1)
- 3 sets of 10-12 reps (80% 1-RM) performed to the point of fatigue (80%-3)
- 3 sets of 30-40 reps (30% 1-RM) performed to the point of fatigue (30%-3)
The figure below shows the change in the size of the quadriceps, measured using magnetic resonance imaging.
As you can see, high reps and light weights (30%-3) stimulated just as much muscle growth as heavy weights and low reps (80%-3).
The average size of both type I and II muscle fibers increased equally with heavy and light loads, suggesting that both fiber types were recruited during training.
Of course, these are the results from just one study. As I’ve explained in The Sherlock Holmes Guide to Separating Fitness Fact from Fiction, drawing conclusions about anything from the findings of one study is never a good idea.
However, it’s not a single, lone piece of information that contradicts a large amount of existing research on the subject, and there are plenty of other studies out there showing multiple benefits of high rep training.
- Light slow-speed training (55-60% of 1-RM, 3 seconds for eccentric and concentric actions) has been shown to increase both whole-body muscle thickness (7%) and maximal strength (33%). The results are comparable to those obtained with heavy normal-speed training (80-90% of 1-RM, 1 second for concentric and eccentric actions), which increased muscle thickness by 9% and maximal strength by 41%.
- Both heavy (4 sets of 8-10 reps with 80-85% of 1-RM) and light training (4 sets of 18-20 reps with 65% of 1-RM) activate the expression of various genes involved in muscle growth.
- In contrast to the conventional wisdom dictating the use of heavy weights for myofibrillar hypertrophy and lighter weights for sarcoplasmic hypertrophy, high reps and light weights (4 sets of 24 reps with 30% of 1-RM) elevate myofibrillar protein synthesis in the quads for 24 hours after exercise to a far greater extent than low reps and heavy weights (4 sets of 5 reps with 90% of 1-RM)
- Light training (not done to failure) also stimulates protein synthesis in connective tissue just as well as heavy training, giving it a role during injury rehabilitation to improve regeneration of connective tissue.
If you want to add muscle mass as fast as your genetics will allow, lifting heavy weights should still be the main focus of your training. But the addition of some high rep work to a program that already includes heavier training is a great way to get bigger and stronger.
One of my favorite ways to incorporate high rep training in my workouts is to use moderate-to-high repetitions (10-15) but with very short (30-40 seconds) inter-set rest periods.
You could also incorporate a back-off set at the end of a series of heavy sets. Two or three heavy sets of 5-8 reps on the squat followed by a lighter set of 20 or 30 reps is one of the best ways to stimulate growth in your thighs.
The legs seem a lot more responsive to volume than the upper body, with an increased training volume shown here and here to accelerate size and strength gains in the legs, but not in the upper body.
Just one word of caution:
If your technique is not all that it could be, especially with a complicated exercise like the squat or deadlift, I recommend that you avoid high reps. If your core strength isn’t up to the job, your form can quickly deteriorate, leaving you open to injury. Stay with lower reps for the time being and just focus on improving your technique.
You can build muscle with low reps. You can build muscle with high reps. For best results, I highly recommend using both.
About Christian Finn
Christian Finn holds a master's degree in exercise science, is a certified personal trainer and has been featured on BBC TV and radio, as well as in Men's Health, Men's Fitness, Muscle & Fitness, Fit Pro, Zest and other popular fitness magazines.
