Did you know that not only your body is going through a daily rhythm, but all your body functions do so too? These body functions, such as your muscle tissues, hormones, or core body temperature are key factors for your exercise performance and success. Some peak at different times than others. And the optimal time for you to exercise depends on which of these you need to be in your favor based on what you want to achieve with your exercise.

When is the best time to exercise based on your circadian rhythm? The best time to exercise depends on the type of exercise and its purpose. In the morning, you can best boost your mood, burn more fat, build muscle mass, and improve your sleep – great for easy aerobic and strength exercises. In the late afternoon/ early evening, you perform your best and are the least injury-prone – great for intensive exercises.

Read on to get a full understanding of:

• Why the timing of exercise is important in the first place
• Why the best time to exercise is either in the morning or in the late afternoon/ early evening
• What specific advantages are to exercise at these times and what that means for you
• Why exercise during the day is your second-best and at night your third-best choice
• What additional factors you should consider, from habit formation to time adaptations to intermittent fasting advantages on exercise
• My personal experiences and your key takeaways

Let’s start with the basic understanding of why exercise timing plays such a vital role and directly connect it with the purpose behind why you want to exercise in the first place.

The Role of Exercise Timing

Why Is the Timing of Exercise So Important

There is no single best timing for exercise for all purposes. But there is a best time for each specific purpose of exercise. So, the first thing is to figure out your purpose behind your exercise, your reason why you want to exercise. Then we can have a look at which timing works best for your individual situation.

But why does timing play a role for exercise in the first place? In short, because it plays a role for everything in your body. And that includes exercise.

Your body controls and optimizes all your functions and allocates a specific time frame to each. This is important because your body cannot do everything at the same time. And this daily rhythm of optimizing the timing of all your body functions is called your circadian rhythm.

Through your circadian rhythm, your body also optimizes functions that are important for your exercise performance. Your body temperature, for example, is a strong indicator of sports performance and has a circadian rhythm. The same is true for your testosterone levels, your muscle tone, your coordination, or your perception of exertion. And for many more factors that are directly or indirectly linked to your exercise.

At the same time, your timing of exercise also has an influence on your body. It can help strengthen your circadian rhythm (aka the timely optimization of all your body functions) if done at the right time. It is more effective to help you boost your mood, improve your sleep, optimize your weight, or build muscle mass at some times than others.

So, to help you figure when the best time for you to exercise is, there are two questions that you should ask yourself:

1. What do you want to achieve while you are exercising?
2. What else do you want to achieve with your exercise?

With your answers to these two questions in mind, have a look at the table below.

Firstly, there are two clear winning time-slots for you to exercise: in the morning and during the late afternoon/ early evening. So let’s have a quick look at these first and the reason why you might want to choose one over the other:

Exercise in the morning to:	Exercise in the late afternoon/ early evening to:
Boost your mood	Perform your best
Build muscle mass and strength	Avoid injury
Improve your sleep	Enjoy the workout more
Control your appetite during the day	Reduce late-night cravings
Burn more fat

If you can’t exercise in the morning or during the late afternoon/ early evening, then during the day is the second-best time for you to exercise. And in many ways, the benefits you receive are intermediary. Though you won’t be able to receive any of these benefits to their full extent.

What if neither of these times works for you? Then exercising in the late evening/ at night is your third-best choice – and much better than nothing. While you won’t get many of the above circadian benefits, you still get one of them. And this one is connected to your insulin sensitivity and blood sugar levels.

In the Morning

What Are the Benefits of Exercising in the Morning

Exercise in the morning is a great way to kick-start your day. And to strengthen your circadian rhythm from the beginning of the day. Especially if you exercise outside.

Just to recap, exercise in the morning is especially beneficial for you if you want to:

• Boost your mood
• Build muscle mass and strength
• Improve your sleep
• Control your appetite during the day
• Burn more fat

And in general, the types of exercises that are especially suited for you in the morning are easy aerobic exercises (think about endurance exercises at a rather easy pace) and strength exercises.

Let’s have a look at the above benefits in more detail now, one at a time.

Boost Your Mood

How to Time Your Exercise to Boost Your Mood

Exercise will boost your mood for the rest of the day. Post-exercise your brain is more relaxed, your ability to experience happiness is increased and your proneness to depression and anxiety is reduced.^​1​

Some studies show that already a single bout of exercise can boost your mood.^​2​ And the good news is that this is also the case if you distract yourself for example by watching TV or even reading.^​3​ So, in case you don’t enjoy exercise itself yet, just distract yourself with something that you do enjoy.

Other studies show that it is especially regular exercise that boosts your mood. Your mood improves post-exercise no matter if you regularly exercise or if you don’t. However, the more regularly you exercise the more you will boost your mood.^​4​ And that difference might even be more than you think. According to some studies, you will boost your mood around twice as much if you regularly exercise.^​5​

Either way, the outcome is clear: exercise boosts your mood for the rest of the day. And when it comes to the timing of when you exercise, let me quote Daniel H. Pink, author of “When: The Scientific Secrets of Perfect Timing” here:^​6​

“When we exercise in the morning, we enjoy its aftereffects the whole day. When we wait to exercise until the evening, we’ll sleep through a good portion of those aftereffects”

Daniel H. Pink

There you have it. Exercise in the morning if you want to boost your mood for the whole day. And it also strengthens the circadian rhythm and the production of those hormones that make you happier. While it weakens those that make you more prone to depression and anxiety.

And if you exercise outdoors, then you also tap into another circadian component that helps you to boost your mood. And this is the circadian interplay of your “sleep hormone” melatonin and your “stress hormone” cortisol.^​7​

Through bright light, like natural sunlight, your circadian rhythm gets the signal that the night is over and the day has started. That means that it shuts down the production of melatonin (that would keep you sleepy) and ramps up the production of cortisol (that energizes you and is beneficial in the morning). The result? You will feel more energized and less sleepy!

Build Muscle Mass and Strength

How to Time Your Exercise to Build Muscle Mass and Strength

Speaking about strengthening and the circadian rhythm. There is one hormone that is more than most associated with strength: testosterone. Testosterone helps you increase your muscle mass and strength (especially through muscle hypertrophy).

Like all other hormones, testosterone also has a circadian rhythm. And it’s levels peak in the morning. To be more precise, depending on your age, your testosterone levels are ten to twenty-five percent higher in the morning than in the afternoon.^​8​

Now, if you want to use exercise especially to build muscle mass and strength, then make use of the circadian rhythm of your testosterone and schedule those workouts in the morning. At the time when your testosterone levels peak.^​1​

Improve Your Sleep

How to Time Your Exercise to Improve Your Sleep

Your central circadian rhythm is controlled by light. And one of the main problems is that you don’t get enough natural light during the day. Which weakens your circadian rhythm. Which then cannot optimize all your body functions.

If you spend most of your time indoors, then you are most likely to only get a fraction of the light exposure you need. To be more precise, it is about 200 times weaker than if you were spending your day outdoors. This is one major factor why you have a weakened circadian rhythm because it expects and needs those natural light intensities. And with a weakened circadian rhythm, you also delay when you are able to fall asleep and you reduce your sleep quality.^​9​

Get to know all about it in this post about “How Does Your Circadian Rhythm Work.”

It is especially beneficial for you to receive more natural light in the morning. And if you exercise outside at this time, you start your day right, with just as much natural light as your body needs to set you up for a strong circadian rhythm.

Proven types of exercise at this time that improve your sleep quality start from just a brisk walk^​1​ and go up in intensity to aerobic exercises like running or cycling^​10​. 

Just to be clear, also exercise in the late afternoon/ early evening helps you improve your sleep quality. But the current research indicates that especially the early morning is the best time for this. Especially between thirty minutes before to two hours after sunrise. Or directly after waking up if sunrise is either too early or too late.

Control Your Appetite

How to Time Your Exercise to Control Your Appetite

Now, this one might be a little surprising to you. But exercise can help you to control your appetite and help you feel less hungry during the day.

In one study, the effects of aerobic exercise on appetite were compared between two groups. One group exercised in the morning. And the other group exercised in the evening. The result? Calorie consumption decreased significantly more in the morning group than in the evening group. And also significant changes for example in body weight and body mass index were found in the morning group. And that after only six weeks.^​11​

Another study aptly titled “Exercise-induced suppression of appetite“ found that people who regularly exercise in the morning report that they feel less hungry for the rest of the day.^​12​ While one more concluded that already one bout of morning exercise significantly increases the “neurologically determined food motivation” aka your drive to eat.^​13​

And here is how exercise in the morning helps you to control your appetite and reduce your hunger. You have a hunger hormone, called ghrelin, and you have satiety hormones. All of which are under your circadian control. Now, when you exercise in the morning then you strengthen that circadian control. And this reduces your hunger hormone and increases your satiety hormones. Both of which help you to control your appetite and reduce your perception of hunger.^​1​

Burn More Fat

How to Time Your Exercise to Burn More Fat

When you wake up in the morning and don’t eat (read: don’t consume any calories) before exercising, you will burn significantly more fat as your energy source. And research has shown that you may even burn twenty percent more fat if you exercise in a fasted state as compared to post-food.^​14​

The reason is that you will use more fat stored in your tissues for your energy. In general, you have two different energy sources available. Glycogen (which is stored in both your muscles and liver) and fat. Glycogen is limited, rather inefficient, but can supply massive amounts of energy quickly. Fat is nearly unlimited (even for the leanest of athletes), much more efficient, but can’t supply massive amounts of energy that quickly.

Overnight, your glycogen stores will deplete to a point. While your fat stores stay virtually the same. To conserve your limited glycogen stores, which need to be saved for vital fight-or-flight situations, your body naturally uses more fat for energy. This is the main reason why you burn more fat when you train in a fasted state.

Now that we are speaking about burning more fat, let’s have a look at one other factor. Your training intensity. The more intensive your exercise is, the relatively higher is the amount of glycogen (and the lower the amount of fat) that you need to burn. Inversely, this means that training at a lower intensity helps you burn off more fat.

But there’s more to it. Over time your body adapts and becomes more efficient at burning fat for energy. Meaning that you will be able to relatively burn more fat at higher and higher intensities.

Do you want to increase your fat burning capacity even further? Exercise in cold air!

Here’s why. And it has to do with two of the different types of fat that you have. White fat and brown fat. Now, brown fat is richer in mitochondria density than white fat. Mitochondria are what enable your body to burn fat as fuel. And the higher your mitochondria density, the higher your capacity to burn fat for fuel. Now, cold air activates brown fat and converts white fat to the intermediary beige fat.^​15​ As a result, you can simply burn some fat by being exposed to cold temperatures.^​16​

Late Afternoon/ Early Evening

What Are the Benefits of Exercising in the Late Afternoon/ Early Evening

One of the big advantages of exercising in the late afternoon until before dinner is that you can make use of the peak performance state your body is in. Which is also the state where you are least prone to injure yourself. Both of these are connected to the circadian rhythm of your core body temperature. Which peaks at this time.

Just to recap, exercise in the late afternoon/ early evening is especially beneficial for you if you want to:

• Perform your best
• Avoid injury
• Enjoy the workout more
• Reduce late-night cravings

And in general, the types of exercises that are especially suited for you in the early afternoon/ late evening are exercises at your peak performance level and endurance exercises that involve high intensities. In addition to those two, you can do any exercise that you want to perceive as relatively easier. 

Let’s have a look at the above benefits in more detail now, one at a time.

Perform at Your Best

How to Time Your Exercise to Perform at Your Best

The circadian rhythm of quite a few of your body functions that are important for your exercise performance peak in the late afternoon/ early evening. Like your core body temperature, your strength, your motor skills, or your reaction time. And while it is easy to connect your strength, motor skills, and reaction time to your performance, the same is also true for your core body temperature. It is highly associated with your exercise performance.^​17​

Lung function is at its peak during the late afternoon/ early evening. At this time your circulatory system can distribute more oxygen and also nutrients.^​18​ Also, blood flow and blood pressure are advantageous for exercise in the afternoon. This combination helps you to get better oxygenation of your muscles.^​19​

In short, if you exercise in the afternoon, you are not only less prone to injuries but you will also perform better. To be more precise, your exercise performance can be as much as twenty-six percent higher during this time of the day than at other times.^​20​

Let’s have a look at three case studies that showcase the peak exercise and sports performance in the late afternoon/ early evening:

1. A disproportionately high number of Olympic records were set in the late afternoon and early evening (especially in running and swimming).^​21​
2. In the NFL, Monday Night Football matches with a start time of 9 pm EST were analyzed for matches between West Coast and East Coast teams for the 1970 to 1994 seasons. 9 pm on the East Coast (EST) is 6 pm on the West Coast (PST), which puts the West Coast teams at a circadian advantage as they were able to play closer to their peak performance time of day. The result? West Coast teams won more often and by more points per game. The performance effect was so strong that their home-field advantage was enhanced and their away-field disadvantage essentially eliminated.^​22​
3. 121 athletes at different levels performed fitness tests at different times of the day. How did the time of day affect their performance? Well, these athletes performed the worst early in the morning (at 7 am), had intermediate performance values during the day (10 am and 1 pm) and at night (10 pm) and performed best in the late afternoon (4 pm) and early evening (7 pm). With performance variations as large as twenty-six percent.^​20​

It seems as if all your body functions align for your peak exercise performance in the afternoon. And next to a peak performance with minimized injury risk, there is one more benefit for you. You perceive this exercise easier than during other times of the day.

Avoid Injury

How to Time Your Exercise to Avoid Injury

All other things being equal, one key indicator of how prone you are to injuries is how well you are warmed up before exercising. Your body temperature has its lowest point while you are sleeping and rises steadily during the day until it peaks in the late afternoon/ early evening. Most people reach their core body temperature peak between 4 pm and 7 pm. When you warm up, you essentially do the same and raise your body temperature and your muscles become warmer. And when your muscles are warmer, they are also more elastic, which makes them less prone to injury.^​17,23​

Also, your strength, motor coordination, and reaction times are at their peak during that time. And these are additional factors that further reduce your chances to get injured.^​20​

You should especially consider moving your exercise session to the afternoon:

• If you have a track record for getting injured.
• If you want to plan an exercise session that carries a comparatively high risk for injuries (like intensive run sessions).
• If you generally want to minimize your chances to get injured.

Enjoy Your Exercise More

How to Time Your Exercise to Enjoy It More

What is another side effect at the time when, among others, your strength, motor coordination, and performance peak? You will perceive your exercise routine as relatively less exhausting than if you did the same during any other time of the day. Simply put, you will be able to enjoy your exercise more.^​6​

When your muscle tone is at its highest and you are at your peak strength, any exercises involving strength are relatively easier. When you are at your peak motor coordination, any exercises involving coordinative tasks will be relatively easier. When you are at your peak reaction time, any exercises where your reaction is imperative will be relatively easier.^​19​

So, if you are not planning on doing an easy exercise, then your afternoon would be your best time. In this way, you could combine a lower injury risk with a higher performance that feels relatively easier. Doesn’t sound too bad, right?

Reduce Late-Night Cravings

How to Time Your Exercise to Reduce Late-Night Cravings

You have seen above that exercise can help you to control your appetite. If you exercise in the morning, you will have those positive effects during the day and beyond. But if you want to specifically target your late-night cravings, exercise in the evening might be just the right time for you.

So, if you normally eat way later or eat much more in the evening than you want to, don’t reach for any pill or other quick fix. Just exercise. Knowing that exercise helps you to reduce your appetite afterward.^​12,24​

Exercise also has another function that is especially helpful for you in the evening: It helps your muscles to take up glucose (the sugar in your blood that comes from any food or drinks with carbohydrates) in a way that is not dependent on insulin.^​25​

Insulin sensitivity has a circadian rhythm that peaks in the morning and steadily goes down during the day until it reaches a low at night. The higher your insulin sensitivity, the less insulin you need. This is, relatively for you, the case in the morning. In the evening and at night, your insulin sensitivity is lower, meaning that your body needs relatively more insulin. And if you consume a lot of carbs at that time, insulin alone might not be sufficient anymore to prevent your blood sugar levels to spike too much.^​26,27​

And here comes exercise. Already as little as twenty-five minutes of exercise will boost your muscles’ ability to take up glucose from your bloodstream. Making you less dependent on insulin at a time when insulin is least efficient for you.

During the Day

What Are the Benefits of Exercising During the Day

If you can’t exercise in the morning or during the late afternoon/ early evening, then during the day is the second-best time for you to exercise. And in many ways, the benefits you receive are intermediary. Though you won’t be able to receive any of these benefits to their full extent.

You will be able to boost your mood for the rest of the day, just as with morning exercise. The main difference is just that the rest of the day is now shorter.^​1​

You will be able to strengthen your circadian rhythm and improve your sleep if you exercise outdoors and get plenty of natural sunlight exposure.^​9​

You will be able to better control your appetite following the exercise. Still knowing that exercise helps you to reduce your appetite afterward.^​12,24​

However, you will not tap into the peak of your testosterone levels that would help you to build strength^​8​ or the peak of your core body temperature, motor skills reaction time, strength, lung function, and blood flow that would help you to perform at your best, avoid injury, and enjoy your exercise a bit more^{​17–20​}.

Late Evening/ at Night

What Are the Benefits of Exercising in the Late Evening/ at Night

Your third-best choice – and much better than nothing – is to exercise in the late evening/ at night. While you won’t get many of the above circadian benefits, you still get one of them. And just like in the morning, easy aerobic exercises (think about endurance exercises at a rather easy pace) are best suited.

Do you remember how exercise in the late afternoon/ early evening not only helps you with your cravings but also with your insulin sensitivity? This is also the main advantage that you can get when you exercise in the late evening/ at night. Besides the positive effects of exercise itself, obviously.

Insulin release and insulin sensitivity are both lower in the evening and at night. This means that your blood sugar will spike more than during the rest of the day after a carbohydrate-rich meal.^​26,27​

Now, when you exercise, your muscles use up parts of their stored glucose. And, as a result, soak up blood glucose (your blood sugar) to top up their storages again. In this way, you can reduce the blood sugar spike after your dinner if you exercise. Or, as Satchin Panda, one of the leading chronobiologist, puts it:^​1​

“For those at risk of type 2 diabetes, any physical activity in the evening is like taking a diabetes pill to reduce blood sugar.”

Satchin Panda

Besides, any easy exercise or physical activity will also help you with your digestion. When you slowly move your body, also your food moves down your digestive tract. This reduces your chance of acid reflux and heartburn at night.^​1​

When it comes to sleeping at night after exercising, there are two things to consider.

On the one hand, exercise generally promotes better sleep quality. And no matter if you do easy or vigorous, high-intensity late-night exercises, none of these were found to worsen or disrupt your sleep.^{​28–30​}

On the other hand, late-night exercise can disrupt your circadian rhythm in two ways. One, if the exercise is too intensive then your body produces too much cortisol (to keep you energized) and suppresses the production of melatonin (to help you sleep). Two, intense exercise also raises your core body temperature and heart rate too much. But both need to be at their lowest point for optimal sleep.^​1​

The way for you to overcome this is to choose easy aerobic exercises instead of intensive exercises in the evening. And also to take a hot shower before going to sleep that will divert blood to your skin and effectively cool down your core body temperature.

Additional Factors

Which Additional Factors Should You Consider

Ok, above we’ve covered the general basics for you to decide at which time of day you want to do which exercise. But there’s more to it:

• Your success depends on whether you can make your new exercise a sustainable habit.
• There are chronotype variations in timing and, over time, your body will adapt to the time you regularly exercise.
• And also your eating timings can positively influence your exercise performance.

Let’s have a look at these points now.

Make Exercise a Habit

How to Make Exercise a Habit

The question of when to exercise to make it a habit is not that straightforward to answer. Because it has two different answers based on your personal situation.

Do you generally find it difficult to make time for exercise? Then exercise in the morning might be the right time for you. Studies suggest that you will be more likely to follow your exercise routine if you schedule it at this time.^​31​

Do you have the time but find it harder to motivate yourself in the long term? Then exercise in the late afternoon/ early evening might be the right time for you. Although it is generally more challenging to find time to exercise in the afternoon/ early evening, studies suggest that you will be more motivated to regularly exercise at this time compared to morning exercise.^​32​

How often should you expect to exercise until it becomes a habit? Well, studies found that if you exercise at least four times a week (bear in mind that those could also be short sessions), then you need at least six weeks to establish your exercise habit. And the most important part of this habit formation was simply to consistently follow an exercise regime.^​33​

Finally one word about your ability to boost your mood. We’ve seen above that already one single session of exercise can boost your mood. But guess what? Over time your mood will be boosted even more. Any given exercise session will boost your mood about twice as much if you regularly exercise as compared to non-regular exercising.^​5​

Your Body and the Time of Day

How Your Body Adapts to the Time of Day

Two more factors that play a role for you to choose the right time to exercise and those are the habit when you regularly exercise as well as your chronotype (more about that below).^​34​

Firstly, it is important to know for you that your body adapts to when you regularly exercise. You will achieve greater adaptations to your exercise, and greater improvements during exercise, at the time of the day when you regularly exercise.^​35,36​

That being said, there are mixed results of how your chronotype influences your optimal exercise time. In short, your chronotype is the expression of your natural sleep-wake-cycle that is based on your circadian rhythm.

You can read all about it in this post about: “What Are Chronotypes and How to Find Out Yours”

Ok, back to how your chronotype influences your exercise.

One study examined the peak power output of cyclists either in the morning (at 7:30 am) or in the late afternoon/ early evening (at 5:30 pm). And they did this study especially with cyclists who had an early chronotype. The result? These cyclists all performed better in the afternoon time-slot. Also taking into account a substantial warm-up to increase core body temperature.^​37​

Other studies found that if you are an early chronotype, you have a relative advantage of competing in the morning against later chronotypes.^​38​ And that early and intermediate chronotypes reach their peak performance levels earlier in their day (about six to seven hours after waking up) than later chronotypes (who need a little more than eleven hours after waking up).^​20​

What does this last part mean for you specifically? Everything stays the same for you if you aren’t an early chronotype. But if you are a rather early chronotype, then try out different exercise times for different days of the week. Your peak performance time might already come around lunchtime and not just in the late afternoon/ early evening. So why not give it a try and find out for yourself?

Intermittent Fasting and Performance

How Intermittent Fasting (Time-Restricted Eating) Improves Your Exercise Performance

You have seen above that exercising in a fasted state helps you burn more fat for fuel. Or, stated otherwise, become more efficient in burning your nearly unlimited fat stores and preserving your limited glycogen stores. Both of which are a competitive advantage for endurance events.

But there’s more to it. Let’s have a look at two studies, one involving mice and the other us humans.

When mice were put on a feeding cycle of only eight to ten hours after which they fasted for fourteen to sixteen hours, what do you think happened? Well, compared to their peer group that was able to eat when they want, these mice that were fasting intermittently had an:^​39​

1. Improved muscle mass
2. Increased endurance exercise capacity
3. Improved motor coordination

One explanation is that many genes that are involved in repairing muscle and growing muscle follow a circadian rhythm and also the feeding cycle. They have their peak production during the day. And muscle repair and rejuvenation were boosted by both a strong circadian rhythm and a clear feeding-fasting cycle. Both of which were strengthened through their feeding cycles.

Now, you are not a mouse. But if you could choose three outcomes from your exercise, I bet at least one of the above would be on your list.

So, let’s have a look at a human study now. Endurance athletes that were already in excellent shape and body composition adopted an intermittent fasting schedule where they ate for eight hours and fasted for sixteen hours. The outcome of this study after ten weeks?^​40​

1. No significant change in muscle mass
2. Significantly reduced fat mass 
3. Many markers of good health improved

Now, if you could choose three outcomes from your exercise again, all three of your desired exercise outcomes would probably be present on both of these lists combined.

Personal Experiences

My Personal Experiences

Now that I shared all those information about how you optimize the timing of your exercises, I guess it’s time to show you how I try to implement this.

I always try to start my day with some form of easy exercise. For me, this could be a swim or an easy run or bike session. And if none of these are scheduled in my training plan for the morning then I am simply going for a short walk. All ideally outside.

And I can feel the positive impact my morning exercise or movement has on my mood. Especially when I am skipping it one day and feel significantly less energized during the day.

Whenever there is a hard exercise session on my training plan, I try to schedule it for the late afternoon/ early evening. And from all the positive effects mentioned above, I can especially contribute to the reduced perception of effort. Those intensive sessions feel especially mentally less challenging and draining. And I look much more forward to these as compared when they are scheduled in the morning.

Speaking about morning exercises, I’ve also implemented fasted sessions. And my body has adapted quite well to these over time. Given that I do intermittent fasting where I only eat for a very few hours every day and follow a keto diet, my fat metabolism is already quite high. And through this, I was gradually able to improve both the intensity and duration of fasted workouts while still keeping them as an easy aerobic effort.

My longest fasted exercise session, for example, was a five-hour bike ride in the Swiss mountains. Without any calories before or during the session. And I never felt like I was running out of energy or badly needed to eat. I didn’t even feel the urge to immediately eat when I arrived back home. I showered, prepared some nice food, and then ate more than enough.

Why am I sharing this with you? To show you from my experience how you can implement your workout sessions to make them work for you. And to also highlight that you will adapt over time. Maybe even much more than you ever thought possible.

Key Takeaways

Key Takeaways

Finally, there are six key takeaways that I want to share with you:

1. Your body goes through a circadian rhythm every day that controls and optimizes all your functions. Through your circadian rhythm, your body optimizes the timing of those functions that are important for your exercise. This is why the time when you exercise plays an important role. And the best time to exercise depends on the type of exercise and its purpose.
2. In the morning, the types of exercises that are best suited for you are easy aerobic exercises (think about endurance exercises at a rather easy pace) and strength exercises. This time is especially beneficial for you if you want to:
   • Boost your mood
   • Build muscle mass and strength
   • Improve your sleep
   • Control your appetite during the day
   • Burn more fat
3. In the late afternoon/ early evening, the types of exercises that are best suited for you are exercises at your peak performance level and endurance exercises that involve high intensities. And any exercise that you want to perceive as relatively easier. This time is especially beneficial for you if you want to:
   • Perform your best
   • Avoid injury
   • Enjoy the workout more
   • Reduce late-night cravings
4. During the day is the second-best time (after both morning and late afternoon/ early evening) for you to exercise. And in many ways, the benefits you receive are intermediary. Though you won’t be able to receive any of these benefits to their full extent.
5. In the late evening/ at night is the third-best time for you to exercise. While you won’t get many of the above circadian benefits, you do get the benefit of better controlling your blood sugar levels that would especially spike after a carbohydrate-rich dinner, at a time when your insulin sensitivity is at a low point.
6. There are additional factors that might help you to choose the right exercise timing:
   • Habit formation: It is generally easier to implement exercise in the morning, but easier to stay motivated to exercise in the afternoon.
   • Time of day adaptations: Your body will adapt to the time when you regularly train. And if you are an early chronotype, try your most intensive exercises around lunchtime.
   • Intermittent fasting (eating for eight hours, fasting for sixteen): Studies show that intermittent fasting strengthens your circadian rhythm and is promising to help you to reduce fat mass, improve muscle mass, improve endurance, improve motor coordination, and improve markers of good health.

And now back to you: If you reflect on your typical day and your motivation to exercise, do you already know which time would be best for you? Or better, at which times during the week you want to implement which exercises?

Stay fit,

PS: If you found this information useful, spread the word and help those who would benefit most from it 🙂

References

References

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   Panda S. The Circadian Code. Rodale Books; 2018.
2. 2.

   Yeung RR. The acute effects of exercise on mood state. Journal of Psychosomatic Research. February 1996:123-141. doi:10.1016/0022-3999(95)00554-4
3. 3.

   Russell W, Pritschet B, Frost B, et al. A comparison of post-exercise mood enhancement across common exercise distraction activities. Journal of Sport Behavior. 2003;26(4):368-382.
4. 4.

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