How Many Days a Week Should I Work Out to Build Huge Muscles?

Workout frequency is a much-debated topic in the fitness world. Is more better? Or do muscles need more recovery to reach their full size potential? The answer is, unfortunately, not cut and dried. While research reveals some benefit to higher training frequencies, it may be total volume that makes more of a difference. Ultimately, it's whatever works best for your own body.

Training frequency is how often you train a single muscle group each week. There are many popular schools of thought on this.

According to competitive bodybuilder Doug Brignole, Arnold Schwarzenegger used to train each body part three times a week: chest, shoulders and back on Mondays, Wednesdays and Fridays, and arms and legs on Tuesdays, Thursdays and Saturdays. That was his bodybuilding training frequency of choice — or at least one of them — and it worked for him.

On the other end of the spectrum, renowned strength coach Charles Poliquin touted the German Volume Training method in which each muscle group is worked only once per week in a very specific volume — 10 sets per exercise. According to Poliquin, this training frequency helped Canadian weightlifter and Olympic silver medalist Jacques Demers build his massive thighs, and it was used by professional bodybuilder Bev Francis in her early career to increase muscle mass.

You can't talk about training frequency without also discussing training volume. Training volume is the amount of work you do in each workout — the number of sets and reps. For example, Brignole explains that Schwarzenegger and his counterparts used to do 20 sets per body part per workout — 60 sets per week. That's quite a high a volume.

Poliquin's German Volume Training method only includes 10 sets of a single exercise per body part per week, which is significantly less than Schwarzenegger's routine.

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If you find such disparity confusing, scientific findings aren't going to do much to clarify. A study published in 2018 in The Journal of Strength and Conditioning concludes that doing eight sets per body part twice a week had only a slight hypertrophic benefit over doing 16 sets once a week.

A 2018 study featured in PeerJ compared the effects of equal-volume once-weekly or twice-weekly training sessions on muscle gain. The group training once a week had significant increases in biceps (elbor flexor) muscle thickness.

But a study published in 2015 in the Journal of Sports Medicine and Physical Fitness showed no differences in hypertrophy between equal-volume workouts performed either once or twice weekly. Another study published in Applied Physiology, Nutrition and Metabolism in 2018 determined that both a high-frequency, low-volume and high-volume, low-frequency training program increased lower body mass, but only the high-volume, low-frequency plan increased upper body mass.

Yet more research muddies the waters. A study published in 2018 in the Journal of Strength & Conditioning Research concluded that high-frequency training volume was no more effective than low-volume training frequency on hypertrophy.

On the other hand, another 2018 study in the Journal of Strength & Conditioning Research found that there were significant hypertrophic benefits of high-frequency training for a group that performed five total-body workouts each week compared to a group that worked out each muscle group only once a week.

And an additional study published in 2016 in the International Journal of Exercise Science showed that there was no difference between equal-volume high- versus low-frequency training.

One wonders if there is a real answer among all this research. There are many variables to consider: the training status of the study participants (trained versus untrained), the methods used to assess growth (lean body mass versus muscle thickness) and the relative difficulty of measuring hypertrophy versus strength, which tends to have much cleaner results, according to competitive powerlifter and trainer Greg Nuckols.

Nuckols conducted extensive analyses of the research on bodybuilding training frequency and found that untrained lifters saw better results from higher training frequencies than did trained lifters. And in studies that assessed hypertrophy using lean muscle mass versus muscle thickness, higher frequencies also tended to have a greater hypertrophic effect, according to Nuckols.

Overall, higher-frequency training had significant benefit over low-frequency training; however, Nuckols notes that this benefit was smaller for trained lifters.

The goal of lifting weights is to stimulate muscle protein synthesis, the post-workout state in which your body is creating muscle protein at a higher rate. Nuckols surmises that higher frequencies are more effective because they catalyze muscle protein synthesis more often throughout the week.

Whether or not more frequent sessions should be low volume or high volume is less clear. There is a dose-response relationship between training volume and muscle growth; more sets lead to greater muscle hypertrophy, according to a systematic review and meta-analysis published in 2017 in the Journal of Sports Sciences. If you do more per-session volume, muscle protein synthesis is increased and extended, explains Nuckols.

Because of that, it's unclear whether more frequent lower volume workouts are more or less effective than less frequent, higher volume workouts.

Ultimately, the answer is to do as much as you have time for but don't overdo it — which leads to overtraining and injury. If you're working out 6 days a week, you're not going to be able to do as much volume per session without it backfiring. If you only train once a week, you may find that you're fatiguing before you can get in as much volume as you'd like. Therefore, your sweet spot might be somewhere in between.

If you're not seeing the results you want with your current routine, first try adding frequency without adding volume, suggest Nuckols. Once you assess your body's response and ability to recover, you can add volume to each session.

Frequency and volume aren't the only factors involved in building big muscles. Rest periods between sets are also important. One to three minutes is the norm, but a study published in 2016 in the Journal of Strength and Conditioning Research showed that participants who rested three minutes between sets gained more muscle than those who rested only one minute, even though the workouts were otherwise identical.

Your nutrition is critical. Even if you found just the right bodybuilding training frequency, if you're not getting enough calories and macronutrients, you won't put on mass. To build muscle, explains body transformation expert Michael Matthews, you need to be in a calorie surplus and consume adequate protein and carbs. This gives your body the energy and raw materials it needs to build muscle.

Last, recovery is just as important as the work you do in the gym. If you sacrifice proper recovery for more gym sessions, you will sabotage your efforts. If you add frequency and find that your workouts suffer, drop the frequency back down.

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