What Is the Best Time to Exercise? (Based on Science)

My motto is that any time is a good time for a workout! However, choosing the right time to exercise can make a big difference to your results.

Different times of day have unique pros and cons, and there’s no one-size-fits-all answer. Morning is my personal favourite time to train, and science suggests morning exercise has major health benefits, especially for weight loss and fat loss. 

Plenty of factors affect the best time to train, though – and that’s why I’ve put together this article. Below, I’ll explore the best time of day to exercise and why it makes a difference. 

I’ll unpack how time of day changes our energy levels, body temperature, metabolic rate, and more. Basically, it’s everything you need to determine when you’ll get the most from your workouts.

If you want to optimise your workout schedule, read on!

Why Does Workout Timing Matter?

There are a few reasons why choosing the right time for exercise is important. The body’s circadian rhythm means our exercise performance varies throughout the day.

Exercise can impact the body differently depending on the time of day. Since our bodies are a complex ecosystem, training will affect our hormone balance, metabolism, mood and sleep differently depending on the time of day we work out.

Research also shows that habitual training time helps set our body clock. This effect is called the ‘temporal specificity’ of exercise – when you pick a regular time for training, your body becomes primed to perform best at that time!

Studies have backed up this idea – after five weeks of routine training, participants had a longer ‘time to exhaustion’ & slower oxygen deficit at their chosen time of day.

Over time, you may get maximum performance at your regular workout time, regardless of whether it’s morning or evening. If you regularly track your workouts, you might pick up on your patterns!

Wondering what time is best for your needs? Let’s dig a bit deeper.

What to Consider When Choosing a Time to Exercise

When it comes to choosing the best time of day to exercise, there are a few factors that you should keep in mind:

Your Body Clock 

Are you the kind of person that springs out of bed whistling Dixie, ready to attack the day, or does the snooze button has a neat thumbprint embedded in it? If opening one eyelid is too much to bear each morning, don’t kid yourself.   

We all have our own ‘body clock’ – some are larks (naturally thriving in the A.M.), and others are night owls. This isn’t just a turn of phrase, as science shows physiological differences in our sleep-wake cycle. 

Translation: if you’re not a morning person, scheduling a pre-sunrise workout only sets you up for failure. You’ll enjoy exercise more if you’re actually feeling motivated!

‘Peak times’ also vary from person to person depending on our individual chronotype (i.e. whether you’re naturally a ‘morning person’ or ‘evening person’). If you feel sluggish at certain times, you might avoid exercising at those hours – or a quick workout could be the boost you need!

Your Schedule

“I don’t have time” is one of the most common reasons we don’t exercise. You’ll have the best results if you schedule your training sessions when you’re least likely to have something “come up” last minute (every single day).

If you know your evenings are packed with kids’ activities, dinner preparation and the bathtime-bedtime routine, you’ll probably struggle to squeeze in a gym session after work. Working out on your lunch break instead can be the perfect solution for time-strapped parents! 

Personally, I love training in the early mornings before there’s anything or anyone else who needs my attention. 

Type of Exercise

Our strength, flexibility, focus, endurance and energy level fluctuate on a 24-hour cycle according to our circadian rhythm. Exercise is a versatile category, with some activities requiring lots of mental focus. Others focus more on strength, flexibility, or cardiovascular fitness – and there’s a separate peak time for each of these!

Workout styles can also affect us in different ways. If you’re new to training, a high-intensity workout in the morning might leave you too exhausted. On the other hand, yoga or tai chi fans might find it the perfect way to unwind after work. 

Your Fitness Goals

Before you decide when to work out, consider the results you want to achieve. For instance, if you’re looking to build muscle, you’ll want to work out when your strength is at a peak, and your body is ready for muscle repair. On the other hand, if your motivation is weight loss or fat loss, supercharging your metabolism is the priority.  

Below I’ll unpack the ideal time to work out depending on your fitness goal – keep reading!

So What Time of Day Should I Work Out?

It all depends on what works best for your needs! However, if I had to choose just one time of day for exercise, morning training would be my pick – and science is on my side. There are so many perks to working out first thing in the day!

If muscle gains, strength, or performance are your number one goal, afternoon or evening training may suit you better. 

Let’s take a look at how the time of day affects your workouts:

Best Time of Day to Exercise for Weight Loss

Morning is the best time to exercise for weight loss and fat loss, especially if you’re training before breakfast.

Training before breakfast burns fat more quickly, as your body burns glycogen (sugar) before fat. After an overnight fast, you’ll hit that point sooner in your workout. AM exercise also boosts your metabolic rate for up to 14 hours, giving your body a fat-burning boost throughout the day. 

The combination of these factors means morning exercisers lose more weight. Working out first thing in the morning also helps stick with it long-term – another essential factor in achieving any weight loss goal. 

Best Time of Day to Exercise for Performance

Are you looking to perform at your peak? Mid-afternoon or evening is the best time of day to work out for optimum strength and performance. You’ll also want to consider the sport or activity since different aspects of ‘performance’ (like strength, flexibility, or focus) have different biological ‘peak times’.

It’s all thanks to our circadian rhythm or ‘body clock’. For example, our cognitive abilities peak around 2pm, improving technical skills in sports like tennis and soccer. For cardiovascular capacity and fine motor control, we perform at our best in the morning.

On the other hand, we’re physically strongest when core body temperature is highest, from about 4pm to 6pm. The increased blood flow helps boost power and strength, adding maximum punch to our training sessions. 

Of course, if you’re already worn out after a hard day’s work, you’ll probably be stronger in the morning – so everyone will be different here.

Best Time of Day to Exercise for Muscle Gain

Aspiring bodybuilders take note – morning is NOT the best time of day to build muscle mass! Instead, for maximum strength and muscle growth, you’ll want to train in the afternoon.

It’s a common myth that morning training helps build muscle quickly, since this is when testosterone levels peak (between 7am and 10am). 

Testosterone is a crucial hormone for muscle repair in both men and women, so many people assume this will maximise their gains.

However, other factors are at play here – our cortisol levels (the ‘wakefulness’ hormone) are also highest in the morning. Cortisol counteracts muscle development, and this likely negates the benefits of the A.M. testosterone boost.

In theory, muscle gains are maximised in the late afternoon, when physical strength and hypertrophy (muscle growth) peak.

Best Time of Day to Exercise for Energy

If you’re keen to naturally boost your energy levels, lunchtime is the ideal window to work out. Swap your lunchroom scrolling session for a quick run outdoors and see how fast the afternoon flies! 

Exercise can be an even better energy booster than caffeine, so you’ll be buzzing at your desk instead of nodding off by 3pm.

Lunchbreak workouts are an excellent solution for busy lifestyles: it doesn’t eat into your personal time, you don’t have to worry about the kids, and you don’t have to wake up extra early. Plus, the calories you consume at lunch are burned by your hardworking muscles!

I know it’s hard to consider giving up your break, but I think there’s nothing better to clear your busy head than a great sweat session. It’s when I get my best ideas! Even just 20 minutes of exercise improves focus and memory, setting you up for a productive afternoon.

Key Takeaways 

You don’t need a health science degree to know consistency is the key to results. And while research points to morning workouts as the best option, it all depends on what works for you.

Consider your energy levels and how your body responds to different types of exercise, then pick a time of day that works for you. If you find a morning workout gives you maximum motivation to tackle the day, go for it! But if evening yoga helps you sleep better, that’s a great reason to keep it up. 

Whether it’s morning, afternoon or evening – as long as you’re doing it consistently, you’ll be reaping the rewards in no time.