Hot flashes at night
Can exercise reduce hot flashes?
In the randomised trials, regular exercise and yoga did not reduce how often hot flashes came compared with women who carried on as usual, and a Cochrane review rated the evidence too weak to call exercise a treatment. Exercise did raise fitness, yoga eased insomnia symptoms, and one small study found fewer flashes in women whose fitness clearly improved.
Almost every leaflet on menopause tells you to exercise, and many women start a walking habit or a yoga class hoping the flashes and the soaked sheets will ease off. This page looks at a narrower question than whether exercise is good for you, which it is: when researchers counted hot flashes before and after months of regular exercise, did the number go down? The question of when in the day to train is covered separately, in exercise before bed.
What the Cochrane review found
Cochrane reviews pool every randomised trial that meets their standards. The review on exercise for hot flushes and night sweats found five trials with 762 women between them. Compared with doing nothing new, exercise made no measurable difference to how often flashes came or how intense they were.
The reviewers rated the evidence as low quality, because the trials reported their methods poorly, disagreed with one another and were imprecise. They could not tell whether exercise did better or worse than yoga. In one trial of only 14 women, hormone therapy reduced flashes more than exercise did. Their conclusion was that there is not enough evidence to say whether exercise works as a treatment for these symptoms, which leaves the question open in both directions.
The MsFLASH trials of yoga and aerobic exercise
The largest single test came from MsFLASH, a US research network funded by the National Institutes of Health. Women aged 40 to 62 with at least 14 hot flashes or night sweats a week were randomly assigned to yoga, aerobic exercise or their usual routine for 12 weeks. Each kept a daily diary of every flash, counting the night ones on waking, so the trial measured exactly the question on this page. The women were in good health, none had a BMI over 37, and anyone who already exercised regularly or practised yoga was left out, so the groups started from the same inactive baseline.
The yoga trial was demanding: a 90-minute class each week, with cooling breathing exercises, restorative poses and a guided relaxation, plus 20 minutes of practice at home on the other days. The women started at around seven or eight flashes a day. After 12 weeks the yoga group had, on average, 0.3 fewer a day than the usual-activity group, a gap small enough to be chance. How much the flashes bothered them did not change either. What did change was sleep: the yoga group reported fewer insomnia symptoms at the end, a result that passed the trial's statistical bar.
The exercise arm put 248 inactive women on moderate aerobic sessions three times a week. According to a summary of the exercise trial, flashes fell by about the same amount in both groups. Fitness went up in the exercisers, and their sleep quality and insomnia scores improved slightly without reaching significance. Flashes dropping in the comparison group too is common in these trials, partly because symptoms vary month to month and partly because women who join a trial pay closer attention to them.
Studies that did find fewer flashes
The picture is not uniformly negative. At Liverpool John Moores University, 21 women with hot flushes after menopause took part in 16 weeks of supervised training or acted as a comparison group, and were brought into a lab where gentle heating set off flushes on cue. In the paper on flush frequency, the women who trained became fitter and reported fewer flushes a week than the comparison group. Their resting core temperature fell slightly, and sweating and skin blood flow switched on earlier as they warmed up, which the authors read as better control of body heat.
That study is small, and in the companion paper most women chose for themselves whether to train, which lets motivated women cluster in one group. It still shows how this programme differed from the big trials. The Liverpool programme was supervised and pushed fitness up measurably. MsFLASH used moderate sessions over a shorter period, and a programme that only nudges fitness may be too light to change temperature control.
Observational studies add another strand. Penn State researchers, whose work is described in the exercise before bed article, found that women with mild to moderate flashes had slightly fewer in the day after being active, while a few individual women had more. Studies of this kind show what tends to go together and cannot prove that the activity caused the change.
Does exercise help night sweats?
Night sweats are hot flashes that happen in sleep, and the trials counted them together, so the answer is the same: no reliable drop in how many come. The sleep around them is a different matter. Both MsFLASH arms pointed towards better sleep, and yoga reached a clear result on insomnia symptoms. For a woman whose real complaint is lying awake after a night flash, that may matter more than the count itself.
The menopause insomnia page covers the treatment with the strongest trial record for that, CBT for insomnia.
What the NHS, the NIA and the Menopause Society say
Official advice reads differently depending on whether it is a self-help list or a treatment guideline. The NHS page on things you can do for menopause symptoms includes exercising regularly among the ways to try to ease hot flushes and night sweats, along with a cool bedroom, lighter clothing and cutting down on triggers. It names yoga and tai chi as relaxing things to try, and weight-bearing exercise for bone strength.
The US National Institute on Aging's page on what you can do about hot flashes leaves exercise off its list and mentions a healthy weight instead.
The Menopause Society's 2023 statement on non-hormone treatments goes furthest. As Healio's report of the statement sets out, it lists exercise and yoga as not recommended for treating hot flashes, because the pooled trials found no effect. It recommends CBT, clinical hypnosis and weight loss among the non-drug approaches with better evidence. These positions fit together: exercise is good general advice for midlife health, and the evidence that it lowers the flash count is too thin to promise it.
Finding out what exercise does for your own flashes
Averages hide women who do respond, and women who get more flashes after a workout. If you want to know which you are, count before you change anything. Two weeks in the printable night diary gives you a starting figure, with each flash marked mild, moderate or severe. Then keep the diary going through about 12 weeks of regular exercise, the length of the big trials, and compare the first fortnight with the last. Keep other changes to a minimum in that time, as the two-week trigger test explains, or you will not know what made the difference.
If a hot gym or a late hard session seems to bring flashes on, cooling down properly before bed usually matters more than dropping the exercise. If the flashes are frequent enough to wear you down despite these changes, a GP can talk through treatments; the hot flashes at night section has more on what else helps.
My take
I wouldn't start exercising to get rid of hot flashes, because the Cochrane review and both MsFLASH arms say most women will be disappointed on that count. I would start for the sleep, the mood and the bones, which is where the evidence is stronger, and treat any drop in flashes as a bonus. If yoga appeals, the MsFLASH result on insomnia is the best reason I found to try it. And I'd judge it by a diary kept for three months, since the one study that found fewer flashes was also the one where women got measurably fitter.