For general health, the U.S. guidelines recommend strength training at least 2 days a week, plus at least 150 minutes of moderate cardio. For building muscle, 3 or 4 days of lifting a week works well for most people. The best number is one you can keep up for months, with enough sets for each muscle.
The right number for you comes down to your schedule, your goals and how long you've been training.
What the guidelines say
The Physical Activity Guidelines for Americans set a minimum for adults:
- Strength training for all major muscle groups on at least 2 days a week.
- Cardio for 150 to 300 minutes a week at a moderate pace, like brisk walking, or 75 to 150 minutes at a hard pace, like running. More brings extra health benefits.
You can fit both into as few as 2 or 3 days if your sessions are long enough, but spreading them through the week is usually easier. A 30-minute walk on five days covers the cardio part on its own.
What the research says about building muscle
For muscle growth, how many hard sets each muscle gets in a week counts for more than how many days you train. A 2019 meta-analysis found that when weekly sets were the same, training a muscle once, twice or three times a week led to about the same growth.
The days still matter in practice. An earlier 2016 meta-analysis found that training each muscle about twice a week tended to build more muscle than once a week. More sessions make it easier to fit in enough sets without any one workout running long, and you stay fresher in each workout. Most popular splits train each muscle twice a week.
A 2024 meta-analysis that compared split routines with full body routines found about the same muscle growth and strength with both, when the total number of sets was similar. That means you can pick whichever split fits your week. For a sense of how many sets to aim for, see How many sets per week to build muscle?
Which routine fits your week
Each number of days has a split that fits it, and we have a routine example for each:
| Days a week | Common split | Routine example |
|---|---|---|
| 2 | Full body twice | 2-day full body |
| 3 | Full body three times, or push, pull, legs once each | Full body or 3-day push pull legs |
| 4 | Upper body twice, lower body twice | Upper lower |
| 5 | Upper lower plus a fifth day, or one muscle group a day | Upper lower plus cardio, or bro split |
| 6 | Push, pull, legs twice each | Push pull legs |
If you'd rather answer a few questions, our Routine Finder matches you with the closest routine example based on your days, your equipment and how long you've been lifting. For a full comparison of the splits themselves, see Push pull legs vs upper lower vs full body.
2 days a week
Two full body workouts a week is enough to build muscle and strength, especially for beginners and busy people. Each workout covers every major muscle, so each one gets trained twice. The sessions run a little longer, about an hour, since there's more to fit in.
3 days a week
Three days is the most common starting point. Full body on Monday, Wednesday and Friday trains each muscle three times a week with a rest day between workouts. It's what our beginner gym workout plan uses. Lifters with a year or more of training often switch to push, pull and legs once each, which gives each workout more sets for fewer muscles.
4 days a week
Four days opens up an upper lower split: two upper body days and two lower body days. Each muscle gets trained twice, and each workout is shorter than a full body day. It's a popular step up after the first few months of lifting.
5 or 6 days a week
Five or six days work well if you enjoy training and recover well, but they aren't required for good results. A 6-day push pull legs split trains each muscle twice with short, focused workouts. On 5 days, many people run upper lower on four and use the fifth for cardio, like our cardio and lifting week example, or try a bro split with one muscle group per day.
More days only help if you recover from them. If your lifts stall, you're sore all the time, or you dread the gym, fewer days is worth trying.
How many rest days?
Most people do well with at least one or two full rest days a week. A rest day can still include some easy movement. A walk, some easy cycling or a mobility routine like our hip and lower back mobility example can help you feel better without adding much fatigue.
Training on back-to-back days is fine when you're working different muscles, like upper body on Monday and lower body on Tuesday. Training the same muscles hard two days in a row makes it harder for them to recover.
Busy weeks and changing schedules
If your schedule changes from week to week, a full body routine is the most forgiving, since a missed day doesn't leave any muscle untrained. If a busy stretch cuts you to fewer days, you can hold on to most of your progress by keeping the same exercises and doing fewer sets until you can train more again.
Common questions
Is working out every day bad?
Moving every day is great. Lifting hard every day, especially the same muscles, makes it hard to recover. Most people get better results with at least one or two lighter or rest days each week.
Is 3 days a week enough to build muscle?
Yes. Three full body workouts a week trains every muscle three times and is enough for most people to build muscle and strength for a long time.
Can I build muscle working out 2 days a week?
Yes, especially if you're newer to lifting. Two full body workouts that train each muscle hard will build muscle. Progress may be a little slower than on more days, mainly because you'll fit in fewer sets.
How long do workouts last?
Most lifting workouts take about 45 to 75 minutes, including rest and a warm-up. Training fewer days usually means a little longer per session. Rest times make the biggest difference to how long a session takes. See How long to rest between sets.
What about cardio days?
Cardio fits on rest days or after lifting. You recover quickly from walking and easy cardio, so they won't get in the way of your lifting. Hard intervals take more out of you, so many people keep them away from heavy leg days.
Sources
- U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition (2018).
- Schoenfeld B.J. et al. Effects of resistance training frequency on measures of muscle hypertrophy: a systematic review and meta-analysis. Sports Medicine (2016).
- Schoenfeld B.J. et al. How many times per week should a muscle be trained to maximize muscle hypertrophy? A systematic review and meta-analysis of studies examining the effects of resistance training frequency. Journal of Sports Sciences (2019).
- Ramos-Campo D.J. et al. Efficacy of split versus full-body resistance training on strength and muscle growth: a systematic review with meta-analysis. Journal of Strength and Conditioning Research (2024).
- Schoenfeld B.J. et al. Dose-response relationship between weekly resistance training volume and increases in muscle mass: a systematic review and meta-analysis. Journal of Sports Sciences (2017).
