Best Rep Range to Build Muscle: Where is the Science Today?

The Traditional Approach to Rep Ranges

When searching for the ideal rep range to train for hypertrophy, you’ll likely come across many tables that outline rep ranges in the same way:

• Strength: 1-5 reps at a high load

• Hypertrophy: 6-12 reps at a moderate load

• Muscular endurance: 12+ reps at a low load

However, it’s essential to note that the number of reps decreases as the load increases.

A New Era of Research

While these recommendations have been staples in exercise science textbooks, much has changed since 2009. In the last several years, an emerging body of literature has evolved our understanding of the ideal rep range for hypertrophy training. Let’s explore the research!

The Case for High Reps/Low Load (Up to 35!)

A 2021 review examined the literature on different rep schemes for hypertrophy training and found that a wide range of rep schemes can be effective, with the lowest effective load of 30% 1RM.

In a study, eighteen resistance-trained men were assigned to either a high-rep, low-load group (25-35 reps) or a low-rep, high-load group (8-12 reps). All other training variables were equated in the eight-week program. At the end of the program, the elbow flexor, elbow extensor, and quad sizes were measured.

The results found that the high-rep and low-rep groups had similar hypertrophy adaptations. However, the study acknowledged that it’s still unclear whether these results will continue beyond the eight-week program.

If High Rep Sets Work Just as Well, Which Muscle Fibers Are Being Adapted?

Low-intensity activity typically adapts type I muscle fibers, while moderate to high-intensity activity adapts type II fibers. Since the benefits of hypertrophy training include growing the size of the type II fibers, will high-rep sets target only the type I fibers? Will this decrease muscle size potential since type I fibers don’t grow as big?

A meta-analysis examined these questions and found no significant differences between low-rep and high-rep on hypertrophy of type I or II fibers in the lower body, as long as each set was taken to failure.

Limitations of High Rep Training

You may think it’s a great idea to start doing 30-rep sets now. Compared to low-rep sets (8-12), high-rep (20+) sets cause more discomfort, a higher rating of perceived exertion, and less enjoyment for most people.

Instead of shifting your entire program to 20+ rep sets, you could make the last set of a muscle group’s workout a high-rep set or something similar.

Is Training to Failure Necessary for Hypertrophy, Regardless of the Rep Scheme?

One standard variable in many research articles on different load schemes was taking each set to failure. High rep sets will only be effective for hypertrophy if taking each set to failure or near failure.

While training to failure is no longer as necessary when training at high load/low reps, it is essential to train to failure or very close to failure with lighter loads/higher reps.

Conclusion

Muscle hypertrophy can be achieved with a large spectrum of rep ranges. The science today suggests that high-rep sets can be just as effective as low-rep sets for building muscle, as long as the load is light enough and each set is taken to failure.

Don’t be afraid to mix up your rep range to keep challenging your muscles and avoiding plateaus.

FAQs

Q: What is the best rep range for building muscle?

A: The best rep range for building muscle is a matter of ongoing research. However, the current scientific consensus suggests that a wide range of rep schemes can be effective, including high-rep sets (20+), moderate-rep sets (6-12), and low-rep sets (1-5).

Q: Do I need to train to failure to build muscle?

A: Yes, training to failure or near failure is essential for hypertrophy, regardless of the rep scheme. This means that you should aim to complete each set with the last few reps being difficult, but not impossible.

Q: Can I use high-rep sets to build muscle?

A: Yes, high-rep sets can be an effective way to build muscle, as long as the load is light enough and each set is taken to failure. However, high-rep sets may cause more discomfort and less enjoyment for most people compared to low-rep sets.

Q: What is the best way to incorporate high-rep sets into my workout routine?

A: You can incorporate high-rep sets into your workout routine by making the last set of a muscle group’s workout a high-rep set or something similar. Alternatively, you can replace one or two low-rep sets with a high-rep set.