Start this argument at the footy club and you’ll be there all night. The early birds reckon a 5am run sets up the whole day. The after-work crowd say they’ve got far more in the tank once the day’s done. And there’s always one bloke who swears you’ll never sleep if you train at night.
As it turns out, they’ve all got a point, and none of them is completely right. There’s been a fair bit of good research on exercise timing in the last few years, including a big study out of the University of Sydney, and it paints a more useful picture than the usual “just do whatever suits you”.
Quick answer
The best time to work out is whatever time you’ll keep doing week after week, because consistency matters far more than the hour on the clock. But there are real differences between morning and evening training, and depending on what you’re after, it can be worth tilting your routine one way or the other.
| If your main goal is… | Lean towards… | Why |
|---|---|---|
| Lifting or running your best on the day | Late afternoon or early evening | Strength and power tend to peak when your body temperature does |
| Building strength over months | Whatever time you can stick to | Morning and evening trainers end up with similar gains |
| Long-term health | Any regular time, with evening looking promising | An Australian study of adults with obesity linked evening activity to the lowest health risks |
| Not wrecking your sleep | Anything except hard sessions in the last hour before bed | Moderate evening exercise doesn’t hurt sleep |
| Training outdoors in a Queensland summer | Early morning or after sunset | Avoid strenuous exercise between 10am and 3pm |
Strength and performance
Your body temperature runs on a daily cycle. It bottoms out in the early hours of the morning and peaks in the late afternoon and early evening, and warmer muscles simply perform better.
A large meta-analysis of 63 randomised controlled trials, summarised by independent research group Examine, found grip strength, jump height and short, flat-out sprint performance were all higher in the late afternoon and early evening than in the morning. Where studies measured grip strength, the peak usually landed somewhere between 2pm and 9pm.
The early risers have a fair comeback, though. When people train at a regular time for weeks and months, morning trainers and evening trainers build similar amounts of strength and muscle. There’s also evidence, reviewed in the Journal of Strength and Conditioning Research, that your body adjusts to when you usually train, so regular morning trainers can push their morning performance up closer to that afternoon peak.
Early bird or night owl?
There’s another wrinkle. Researchers at the University of Birmingham tested 20 competitive athletes at six different times of day, after sorting them into early types, in-between types and late types (night owls) based on their natural sleep patterns.
The early types peaked around midday, the in-betweens just before 4pm, and the night owls not long before 8pm. The night owls were hit hardest by early sessions, performing about 26% below their peak first thing in the morning.
It was a small study of athletes, so it’s not gospel for the rest of us. But if you’re a natural night owl dragging yourself out for 5am sessions and wondering why you feel flat, this could be part of the reason.
Health: an Australian study backed evening exercise
In 2023, a team at the University of Sydney’s Charles Perkins Centre, led by exercise physiologist Angelo Sabag, published a study in the journal Diabetes Care. Using activity tracker data from almost 30,000 adults with obesity in the UK Biobank, they grouped people by when they did most of their moderate-to-vigorous activity: morning, afternoon or evening.
People who did regular bursts of moderate-to-vigorous activity at any time of day did better than those who didn’t. But the evening group, exercising between 6pm and midnight, had the lowest risk of dying over the study period, along with the lowest rates of heart disease and of the small blood vessel problems linked to diabetes.
The researchers think it comes down to blood sugar control. The body is more resistant to insulin later in the day, and evening activity may help counter that, particularly in people who already have trouble managing their blood sugar.
A few things to keep in mind. The people in the study were older adults with obesity, with an average age of 62. It found a link rather than proving cause and effect, and evening exercisers may differ in other ways too. Morning exercise still came out well ahead of none at all. The lead researcher also made the point that short bursts count, even something like taking the stairs.
Does exercising at night wreck your sleep?
For most people, no.
Researchers at ETH Zurich reviewed 23 studies on evening exercise and sleep for the journal Sports Medicine. They found evening exercise didn’t harm sleep in healthy adults, and people actually spent slightly more of the night in deep sleep after an evening session. Moderate exercise caused no problems even when it finished just 30 minutes before bed.
The exception was vigorous exercise finishing within about an hour of bedtime, which may make it harder to drop off. Their rule of thumb is that it’s vigorous if you’re working too hard to hold a conversation. So hard intervals at 9:30pm with lights out at 10 probably isn’t a great idea, but an evening walk, a gym session or social touch after work should be fine. If you do find yourself lying awake afterwards, the researchers’ advice is to just shift your session a bit earlier.
Is morning best for fat loss?
You’ll see plenty of claims that training on an empty stomach first thing is the trick to burning fat. None of the big timing studies above actually tested that, so I wouldn’t build your routine around it. For weight loss, what you eat and how much you move across the whole week matter a lot more than what time you do it.
Training in the Queensland heat
In theory, late afternoon is ideal for performance. In practice, 3pm in a Brisbane summer is more like training in a sauna with the door shut.
Queensland Health advises against strenuous activity during the hottest part of the day, usually between 10am and 3pm. In summer, that pushes outdoor training to early morning or after the sun’s gone down. Drink plenty of water, stick to the shade where you can, and pull up if you get a headache or start feeling dizzy or sick.
There’s nothing wrong with being a morning trainer in summer and an evening trainer in winter. It’s just working with the climate.
Make it fit your day
For a lot of tradies and site workers, the natural window is straight after knock-off, when you’re already warmed up, it’s still light and the evening’s ahead of you. Office workers might do better with a lunchtime walk or an early session before the commute. Whatever suits your day best, the research says it’ll do you good as long as you keep turning up.
And if all you can fit in is ten minutes, that still counts. A few sets of push-ups while dinner’s cooking gets you towards the two days of strength work Australia’s guidelines recommend.
Cheers.