How to do it
- Two sessions a week. Fewer than three did about as well as three or more.
- Start light and add weight over weeks. Heavy loads showed the biggest effects, and that's where you arrive, not where you start.
- No gym? Squats and push-ups at home to begin with. Add weight when they get easy; heavier tended to do more.
- Don't train your grip for your brain. Weak grip is a warning sign in older age, not a switch you can flip.
How the lifting adds up
- Loadheavier looked better
Trials at three quarters or more of the most a person could lift once showed over twice the effect of trials at half or less. The ranges overlapped, and the authors treat it as a lead, not a finding.
- Frequencytwice is enough
Fewer than three sessions a week did about as well as three or more.
- Volumemore didn't clearly help
Under two hours a week had the biggest effect. Above three hours, the effect was no longer clear.
- Yousymptoms ease
Over weeks, most often 8 or 12, in adults diagnosed with depression. Whether it does the same for an ordinary flat week hasn't been tested.
Why it works
Across 29 trials in adults diagnosed with depression, weeks of lifting eased symptoms compared with control groups. Evidence: decent Those controls mostly did no structured exercise, so this doesn't show how lifting compares with running or walking. Evidence: decent
Heavy loads showed bigger effects than light ones, though the authors treat that difference as a lead, not a finding. Two sessions a week did about as well as three or more. Evidence: decent Heavy is where you end up after some weeks, not where you start.
The long readEvery step of the chain, each study with its numbers, and what's still unproven. 3 min read.
What happens in your brain
This chain is the dose, not brain areas. What the trials measured is depression scores, not what changed inside your head. For the candidate routes, see move hard three times a week.
Load: heavier looked better. Trials at 75 per cent or more of a one-rep max, the most a person can lift once, showed an effect more than twice the size of trials at 50 per cent or less. Evidence: decent The ranges overlapped, and the authors say their dose comparisons didn't show consistent differences. Evidence: decent
Frequency: twice is enough. Fewer than three sessions a week did about as well as three or more. Evidence: decent
Volume: more didn't clearly help. Under 120 minutes a week had the biggest effect; above 180, the effect was no longer clear. Evidence: decent
You: symptoms ease. The commonest programme lengths were 8 and 12 weeks; the full range was 4 to 48. Evidence: decent Whether an ordinary flat week responds the same way hasn't been tested. Evidence: decent
The proof
- A 2025 review pooled 29 randomised trials: 2,036 adults with clinically diagnosed depression, lifting for 4 to 48 weeks. Against control groups, symptoms fell, with a standardised effect of 0.94. A standardised effect is a way of comparing results across different questionnaires. Evidence: decent
- Heavy loads, 75 per cent of a one-rep max or more, came out at 1.32 on that scale. Light loads, 50 per cent or less, came out at 0.56. The heavy estimate ranged from 0.45 to 2.18, so the two overlap, and the authors call all their dose comparisons hypothesis-generating. Evidence: decent
- Fewer than three sessions a week against three or more made little difference. Under 120 minutes a week had the biggest effect, and above 180 the effect was no longer statistically clear. Evidence: decent
- Only one of the 29 trials was at low risk of bias, and results varied a lot between trials. You can't hide from people that they're lifting, so part of the effect may be expectation. Evidence: decent
- In 15 long-running studies of older adults, weak grip went with 1.99 times the risk of cognitive decline and 1.54 times the risk of dementia. Evidence: worth trying That makes grip a marker of general frailty. Nobody has shown that training grip on its own changes the risk. Evidence: worth trying
How to do it
- Two sessions a week. Fewer than three did about as well as more. Evidence: decent
- Start light and add weight over weeks. Heavy loads showed the biggest effects, but that's the destination. Evidence: decent
- No gym? Squats and push-ups at home to begin with. Add weight when they get easy.
- No need to go past about three hours a week. Above that, the effect was no longer clear. Evidence: decent
- If you'd rather run or cycle, move hard three times a week covers that. If starting is the hard part, lower the bar for the gym.
Watch out
The trials were in adults diagnosed with depression. Whether lifting does the same for an ordinary flat week hasn't been tested. Evidence: decent Only one trial in 29 was at low risk of bias, and the results varied widely. Evidence: decent The dose findings, heavier and under three hours a week, are leads, not firm results. Evidence: decent
Weak grip goes with higher dementia risk in long studies of older adults. Nobody has shown that training grip on its own lowers that risk. Evidence: worth trying Don't buy a grip trainer for your brain.
If you have a heart condition or high blood pressure, check with your doctor before hard exercise. Build up the load over weeks. If you've been low for weeks, lift alongside a doctor, not instead of one. See two questions, then a doctor.