How Often Should You Lift Weights?

Most adults should lift weights or do other muscle-strengthening exercise at least 2 days a week. The federal Physical Activity Guidelines for Americans call for muscle-strengthening activity of moderate or greater intensity that works all major muscle groups on 2 or more days a week (HHS). Research backs that minimum. The American College of Sports Medicine’s 2026 position stand found that training at least twice a week improved strength more than training less often. For muscle growth, the number of days mattered much less than the total amount of work you did across the week (ACSM, 2026).

What the official guidelines say

The 2 days a week figure comes up again and again. The CDC says you need muscle-strengthening activity at least 2 days a week, on top of aerobic activity, and that it should work the legs, hips, back, chest, abdomen, shoulders and arms (CDC). The NHS gives the same advice for adults aged 19 to 64: strengthening activities that work all the major muscle groups on at least 2 days a week (NHS).

The current U.S. guidelines are the second edition. HHS is preparing a supplement on steps and muscle-strengthening activity, due out in 2027, which will add to the second edition’s recommendations (ODPHP). Until it’s published, 2 or more days a week is the federal guidance.

Few people meet it. The 2026 ACSM paper cites self-reported data suggesting that only about 30% of American adults do muscle-strengthening activity at least 2 days a week, and nearly 60% do none (ACSM, 2026).

Does lifting more often help?

For strength

More frequent training tends to build more strength, mostly because it lets you do more total work. A 2018 meta-analysis of 22 studies found that strength gains grew with how often people trained, with effect sizes of 0.74, 0.82, 0.93 and 1.08 for training 1, 2, 3 and 4 or more times a week. When the studies matched total weekly volume between groups, though, frequency had no significant effect. The authors concluded that the benefit seems to come mainly from the extra volume that more sessions allow (Grgic et al., 2018).

A newer set of meta-regressions, covering 67 studies, found that strength gains rise with frequency but with diminishing returns (Pelland et al., 2026). The 2026 ACSM position stand recommends at least 2 sessions a week for strength. It couldn’t determine an upper limit, didn’t find enough evidence for a clear dose-response, and notes that the effect of frequency shrinks when volume is equal (ACSM, 2026).

For muscle size

The research here has changed over time. A 2016 meta-analysis of 10 studies concluded that training a muscle group twice a week built more muscle than once a week, and recommended training major muscle groups at least twice a week (Schoenfeld et al., 2016). An updated 2019 meta-analysis from the same lead author, with 25 studies, found no significant difference between higher and lower frequencies when weekly volume was equal. It called the evidence strong and said people can choose how often to train each muscle based on personal preference (Schoenfeld et al., 2019).

The newer findings agree with each other. The 2026 ACSM position stand found that muscle growth was the same whether people trained 1 day a week or more than 5 days a week, as long as total volume was equal (ACSM, 2026), and the 2026 meta-regressions found frequency’s effect on muscle growth compatible with negligible effects (Pelland et al., 2026). What drives growth is weekly volume: the ACSM review linked 10 or more sets per muscle group per week to more growth (ACSM, 2026). Our guide on how many sets and reps explains how to count them.

Beginners versus experienced lifters

The 2009 ACSM position stand recommended different frequencies by experience: 2 to 3 days a week for beginners, 3 to 4 for intermediate lifters and 4 to 5 for advanced lifters (ACSM, 2009). The 2026 position stand, which updates it, doesn’t split frequency by experience and says its recommendations apply to everyone from complete novices to experienced lifters. It also points out that the 2009 advice for beginners to train two or three full-body sessions a week for muscle growth was based on only three studies with 59 participants in total, two of which didn’t actually test frequency (ACSM, 2026). Because the 2026 statement is newer and updates the 2009 one, its advice is the current ACSM position: at least 2 sessions a week, at any level of experience.

Choosing a weekly schedule

Because weekly volume matters more than the number of sessions, you have plenty of options:

• 2 full-body sessions a week. This meets the guideline and the ACSM minimum for strength.
• 3 full-body sessions a week. Each session can be shorter, since the weekly sets are spread across more days.
• 4 sessions split into upper body and lower body. Each muscle group still gets trained twice a week.

Pick a schedule you can keep up. The 2026 ACSM authors say that tailoring programs to the person to get them doing resistance training matters more than meeting specific prescription criteria (ACSM, 2026). If consistency is the hard part, our guide on how to make exercise a habit may help.

Remember aerobic activity too. The federal guidelines recommend 150 to 300 minutes a week of moderate-intensity aerobic activity, or 75 to 150 minutes of vigorous activity, in addition to muscle strengthening (HHS). See how much exercise you need for the full picture.

If you’re short on time

Doing something is better than nothing. The 2026 ACSM review found that many forms of resistance training, including home-based and elastic band training, improved outcomes compared with no exercise, and its authors note that minimal doses of resistance training can bring substantial gains in strength, muscle size and physical function (ACSM, 2026). The federal guidelines say that inactive people should “start low and go slow,” gradually increasing how often and how long they’re active (HHS).

Older adults and health conditions

The same 2 days a week guideline applies to older adults. Their activity should also include balance training along with aerobic and muscle-strengthening activities, and they should judge their effort relative to their own fitness level (HHS). Adults with chronic conditions or disabilities who are able should also strength train on 2 or more days a week. If you have a chronic condition or symptoms, the guidelines say to be under the care of a health care provider, and pregnant women can ask their provider whether or how to adjust their activity (same source). The NHS adds that if you haven’t exercised for some time or have medical conditions or concerns, you should speak to your doctor first (NHS).