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It’s Time to Ditch the One-Time-Per-Week Muscle Mentality

Reading Time: 2 minutes 30 seconds

BY: Mark Chua

DATE: 2022-04-01

What do you think clients prefer:

  1. Muscle size gain in 6 months, or

  2. Muscle size gain in 8 months?

I’m guessing most would answer “1”; greater gains in less time, right?

When designing a hypertrophy program, the goal is to increase muscle mass as quickly as possible. The science behind hypertrophy training evolves over the years. So, how do we train for muscle growth most efficiently? Let’s take a look.

The Old Way – One Muscle Group, Once a Week

Years ago, it was popular to have a chest day once a week. It was always Monday because, of course, you train the “mirror muscles” on Monday when you’re fresh. There was also a back day, a leg day, and so on, for all the major muscle groups. The “rule” was this: Train each muscle group hard, once per week. Then, give that muscle group a full seven days to recover.

But what if those muscle groups didn’t take seven days to recover? Modern findings challenge this rule, meaning you and your client can train for faster hypertrophy gains.

Train Muscle Groups Twice per Week

The latest research shows that muscle groups can fully recover and be ready for more training within three days after a hard training session.1 So, Monday’s “National Chest Day” can be followed by another one on Thursday.

Why is this important? When talking about hypertrophy, total volume is a huge factor.

Total Volume=  Sets x Weight x Reps (during a training cycle)

When you engage in more training, at a significant intensity (65-85% 1 RM), you get more and faster muscle growth. A meta-analysis by Schoenfeld et al.2 observed that participants who performed two training sessions per week for each muscle group increased hypertrophy by 6.8% over 6-12 weeks. Those who trained each muscle group once per week experienced only a 3.7% increase in muscle growth.

That’s 48% more growth for the group using the method of training muscles twice a week!

The plot below gives a visual image of the average results; all favoring a two-per-week approach to training each muscle group:

What about Training More than Twice a Week?

So if twice a week works well, why not train each muscle group three, four, or even five times per week? More training equals more gains, right?

Some researchers have hypothesized that training a muscle group three or more times per week could potentially result in increased hypertrophy, but there is a point of diminishing returns. And research on training at those frequencies is still lacking. Also, if muscle groups haven’t recovered enough by the next training session, the additional work may be detrimental to overall progress.

With that being said, different muscle groups tend to have different rates of recovery, with smaller muscles—biceps, triceps, calves—being able to recover more quickly than larger muscles—lats, quads, hamstrings, etc. 

In addition, different individuals are able to handle different amounts of training volume. Factors outside of the gym—sleep, nutrition, total caloric intake, stress—can significantly affect progress as well. So, yes, you could potentially train each muscle more than two times per week for greater gains, but it may be an individual difference rather than a broad training recommendation that you can make for your clients.

What’s the big takeaway? If you are training each muscle group once per week, you’re likely losing out on some gains. For you or for your clients, if you want bigger muscles faster, train each muscle group two times per week. Learn more about hypertrophy and training muscle groups in our comprehensive Bodybuilding Certification program. 

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1. Scientific Principles of Strength Training; p.193; Dr. Mike Israetel

2. Schoenfeld BJ, et al.  2016. Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis;  Sports Med. 2016; Sports Med.  2016 Nov;46(11):1689-1697. doi: 10.1007/s40279-016-0543-8.

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