Morning, Night, Or Noon? The Science Behind Running Times

Starting the day with a run, having a shower, and heading off to work may leave you feeling fresh and energized and like you’re hitting goals and ticking exercise off the list before your day has even begun. But does this mean that it’s the best time for your body? While everyone is different and prefers to exercise at different times of the day, there are some data that can’t be ignored.

Studies suggest that running in the late afternoon or evening is when our bodies are best set up to maximize our performance. Various factors from person to person and exercise time should be evaluated based on performance efficiency as well as motivation.

There’s more to the story–perhaps your performance might be higher in the evening, but does that mean it’s the best time for you? Well, if you aren’t motivated to go in the evening and running seems like a huge chore, then perhaps it’d be self-defeating to run at that time. Let’s find out more.

Is There Scientifically A Best Time Of the Day To Run?

Controversially, yes. While everyone is different and has their own preferences, there is actually a time of day when your body (on average) is more suited to running than at other times. This means that you are likely to perform better with the same or even less effort than at other times of the day. Studies show that evenings are the peak performance time. (source)

Our bodies have what are known as circadian rhythms, controlled by the hypothalamus in our brains. Most commonly, it is known as a body clock, but this simplifies what is actually happening. Almost every function in our body runs rhythmically on a twenty-four-hour basis.

This rise and fall in our core body temperature, reflex, breathing capacity, hormone levels, and energy stores mean that we can improve the performance of something we do if we choose to do it at the right time of day, that is, the time of time our bodies are most ready to perform that task.

Daylight, social contact, and mealtimes are all factors that contribute to determining our circadian rhythms, which means that people who work night shifts or other ‘irregular’ work shifts on a regular basis will have a different circadian rhythm to the rest of us who work daytime jobs, eat our meals and see other people during these hours. So for most of us operating on a “normal” schedule, running in the evenings is best.

The key point could very well be simply body temperature. In this study, they linked that alertness and reaction times were impacted up to 10% by a lower body temperature.

But My Circadian Rhythm Is Different!

Studies suggest that most people (over 92% in one study) follow the same 12-hour or 24-hour circadian rhythm.

You might initially be thinking “hey! That must apply to someone else–what about my weird sleeping hours and circadian rhythm?”

You could be right–you might have a different circadian rhythm than average–but even this is tricky to manage, since most people (source) follow the circadian rhythm pretty closely, so it’s probably rare if you are totally different from someone else.

Motivation And the Secret Of “Rating Of Perceived Exertion”

Performing exercise at your non-preferred time provides more stress on your brain.

The measure of how hard something is for exercise scientists is called the Rating of Perceived Exertion.

Have you ever heard the phrase, “she’s a morning person”, or “he’s a night owl?” For some reason that hasn’t quite been pinned down yet, some people prefer to do things in the morning, and others in the evening or the night.

I’m one of those morning people–I’m writing this post at 5:32 AM in fact.

Just because, however, I may prefer to exercise in the mornings doesn’t mean it’s the time where my body is at its peak performance.

However, the mornings are when it’s easiest for my brain to exercise. Exercising in the evening feels like it’s harder even if I perform better.

I feel better knowing that in these two studies (this one and this one) that this is confirmed. No matter how you perform, your brain thinks it’s harder to work out at your non-preferred time of day. So if you enjoy running in the morning, it’s probably going to be harder, mentally, to run in the evening.

So If I Perform Better In The Evening, Is That When I Should Exercise?

The answer is no! Just because your body may be better prepared to run in the evening doesn’t mean this is the right time for you.

For example, if you live in Texas, the temperatures in the morning during the summer can easily be in the high 70s low 80s (Fahrenheit) (between 24C and 27C for my friends elsewhere than the US). And in the evening, it could be a roasting 100F (37C).

Running in super hot conditions like this can be dangerous in the worst case, or just entirely de-motivating in the best case. I don’t like running in an oven, so I choose to run in the morning.

In fact, this study shows that our body’s capacity to run in hot weather is greatest in the morning–perhaps due to our lower starting body temperature.

Past that, if running feels harder in the evening for you, then it doesn’t matter how good it is for your body because you won’t want to go. Exercise at any time is better than no exercise. The difference in performance between morning and night is small, so don’t let it stop you from reaching your running goals.

The Why Behind Better Performance In the Evening

To understand why we might perform better in the evening, let’s talk about performance in the morning.

Why Your Body Performs Worse In the Morning

If you think about it, your body has just woken up from a state where your blood temperature is at its lowest–while you are sleeping. In fact, your body temperature drops by a couple of degrees every time you sleep (webmd).

When you wake up, your body still has a lower body temperature. Why does this matter? When your blood is colder, it holds less oxygen. Oxygen is essential for running and exercise in general, so that means our bodies could perform slightly worse.

Waking up doesn’t instantly raise our blood temperature. It’s a process our body has to perform every day and if you don’t do anything about it, it could take some time.

To counteract the lower body temperature, the recommendation from this study is to do a longer warm-up.

Furthermore, if you’re like some people, you don’t like eating right before running, so that means your body doesn’t have the same large source of available energy to burn while running.

Lastly, there is a higher risk of cardiac arrest (heart problems) in the morning (source). It’s not been proven whether that’s due to exercise in the morning, but the conditions are such in our bodies where we are most vulnerable at this time.

Why Our Body Performs Better In the Evening

Body temperature peaks during the mid to late afternoon, and athletes perform better at a higher body temperature. Muscles are more supple, lung function is at its highest point of the day.

While this is physically the best time of day for us to run, it can also be one of the hardest, mentally. Finding motivation after a long day of work can be difficult, but if you can overcome this psychological obstacle, then once you start running, you won’t feel like you’re pushing yourself as hard as other times of the day.

Advantages and Disadvantages of Running Morning, Noon, and Night

Okay, so you understand that some times of the day are physically better and other times are psychologically better, but here’s the overall picture. Ultimately, you need to pick out the time of day that works best with your schedule, and when you will benefit the most from the type of training you’re doing and for the mental benefits, you’re looking to gain from running.

Running Time	Advantages	Disadvantages
Morning	* Often leaves people refreshed and ready to start the day * Works best for people who are most motivated in the morning * Warming up your body will also give a boost of oxygen to the brain, making you feel ready for the rest of the day * Metabolism pushed to burn more calories * Testosterone, which is used for muscle building, is at its highest level during the day between 5:30 and 8 am. Testosterone helps our body create muscle proteins. (source)	* Feels more difficult for those not motivated in the morning. * Joints are stiff and muscles are inflexible before warming up, which could lead to injury
Noon	* Energy stores are up from breakfast and you are mentally and physically more awake than mornings * Psychologically good for a mental break and afternoon focus and productivity	* Can feel slow or have digestive issues after eating * Bodily functions in a natural lull, meaning it’s not physically the optimal time of day to be running and can still feel like hard work
Night	* The body is in performance mode, with most functioning at its optimal for running * Night-time fat burning is boosted * Mentally can be a great way to destress after a long day	* Running before bed can make it hard to fall asleep for some, as the body is energized by the workout. Some don’t have this problem, however. * Mentally can be difficult to motivate yourself after a long day when you are feeling psychologically exhausted

Do You Run Faster In the Morning Or At Night?

If you run on a normal schedule, meaning you sleep during the night and are awake during the daytime, then your body, on average, will run faster at night. The key is to run when your core body temperature is at its highest during the day.

This leads to a number of benefits in our bodies, including; an increase in our blood flow and more oxygen and energy being sent to our muscles; better lubrication of our joints; higher levels of energy and increased stamina; an increase in the speed of nerve impulse, improved breakdown of glucose and glycogen stores, and lower risks of injury.

As our core body temperature is at its lowest first thing in the morning when we wake up after a long period of rest, and gradually increases during the day, peaking in the mid to late afternoon, this is the best time to run, and our bodies will perform best at this time.

With less physical effort, we are likely to run at the same speed or faster than at other times of day, so if improving your time is what you’re aiming to improve on, then testing yourself consistently later in the day is the way to go.

Tips for Morning Runs

If you choose to run in the mornings, these tips will help you to make the most of fighting against your body’s urge to resist the run and to enjoy the run in a way that won’t leave you injured, wishing you’d stayed in bed a little longer!

• Caffeinate! If eating early in the morning is not what you feel like, caffeine has been shown to help in performance, if for nothing else, mentally.
• Eat a light snack before you run if you can. This will prevent you from running on an empty tank and help to boost your speed and energy levels on the run. Something simple, like a piece of fruit or a piece of toast half an hour before you run, can really help.
• Warm-up. Before you start sprinting for time, go for a slow jog–your body temperature is lowest in the morning so if you can start the upward tick of body temperature by a warm up, you are doing what you can to enhance your performance

Morning runs on an empty stomach can help you to burn calories throughout the morning, long after you have finished running. Running in the morning can also help you to feel productive as you start the day ticking something off your list, even if it means mean less sleep and potentially feeling physically tired the remainder of the day.

Tips For Lunchtime Runs

You’re not a morning person and have a social or family life in the evenings, so maybe running at lunchtime is your only option or the most efficient use of your time. 

Alternatively, you struggle to focus in the afternoons, and going for a lunchtime run helps to break up your day and encourages you to start with a clean mental slate for the afternoon. This can be a great way to increase your productivity if you struggle in general in the afternoons.

• Either eat a light snack late morning or else make sure that you eat after you’ve showered before getting back to work after your run.
• High-intensity runs can work really well at this time of day.

Tips For Evening Runs

Your body wants to run now, but your mind might not after a long day at the office. How to make the most of running at this time of day? Let’s find out.

• Get yourself out the door! This is equally an unmotivating time to run as the morning. All you’re likely to feel like doing is going home to collapse on the couch and chill. Remind yourself that no matter how much you don’t feel like running, you never regret it. Once the endorphins start flowing, you’ll be glad that you went, got rid of some stress, and decompressed from the day. It’ll help you relax during the evening.
• If you ate lunch, there’s no need to eat beforehand. Plan your run so that you’re eating dinner within an hour of ending your run in order to replenish your energy.
• Sometimes it helps me to not go home at all after work, but instead change into my workout clothes right after work and then going directly afterward. If I do this, the fridge and the couch are not able to tempt me.

Should I Stretch Before Or After Running?

There is no concrete evidence to support that stretching makes a remarkable difference in exercise. This study of multiple studies basically concludes that you can stretch if you want, but it’s not clear that it helps in performance, or even prevents injury or soreness (regardless of when you stretch, before or after exercise).

In fact, some argue that it could even harm performance and encourage injury, but either way there isn’t enough evidence to make a solid recommendation for everyone.

Is Running Twice A Day Bad?

The short answer is that running twice a day is not bad in itself if done correctly. If not done correctly, you can overexert yourself and increase the risk of injury and long-term damage to your body. The key aspect of getting this right is to allow for enough rest between your runs and to focus your training sessions differently, not just aiming to get as many miles as possible on each run.

For more tips about running twice a day and how you can balance your two daily runs for maximum performance (as well as some downsides), check out our article, here.

If you’re looking to increase your mileage, and that is your motivation for running twice a day, then it might actually be more beneficial for you to add an extra day of running in the week or to extend the mileage on your current training sessions. Particularly if you’re training for a marathon, building endurance is vital, so breaking up your long run isn’t ideal for your training.

Increasing your blood flow to active muscles and teaching your body to recover faster, as well as depleting your glycogen levels and burning fat faster, are two advantages of running doubles. (source) However, if you’re a beginner or intermediate runner, it can be less beneficial to improving your fitness than running fewer, longer runs and can be detrimental to your body If you don’t rest sufficiently between runs. (source)

Resting for six to eight hours between sessions, as well as properly taking a break on your off days, is very important.

Aside from being more time-consuming, running in the morning and the evening can build mental strength and take advantage of different parts of your circadian rhythm to improve your overall performance. Make sure that morning runs include a proper warm-up and that you eat enough to recover after each run to prevent injury and muscle loss with the increased runs.

How Long Should You Run For?

How far or how fast you run is totally a matter of personal preference and ability. You might be running to get some tone into your legs, or training for a marathon, or just to de-stress a few times a week. Whatever it is, there is no minimum or maximum number of miles that you should or shouldn’t be running. You know your body best and how much to push yourself.

If you are aiming to maintain a basic level of fitness, then 150 minutes of moderate exercise a week is advised. (heart.org) This could mean five thirty-minute runs a week or a fewer number of longer runs.

If you’re working towards a marathon or half marathon, which is distance-based, then you’ll want to aim for building up to within ten to twenty miles per week, depending on your goal. How long this takes you, or you end up running per week, is up to you and how hard you push yourself. Are you aiming to complete a race in a specific amount of time? Or just to finish it at all?

Check out our training plan for a half marathon, here for more specific weekly running goals so you can know how much to run per week.

For better levels of fitness, 300 minutes is suggested, which would mean an hour of exercise five times a week. However, note that these are just general guidelines, and this is moderate exercise. If you do intervals or push yourself hard during your runs, you can achieve similar levels of fitness in less time. 

If you’re aiming for a certain distance or amount of time per week, it will likely be easier achieved if you include some variety in your training. This may be a combination of outdoor running and treadmill running, or it may be mixing it up with running both flats and hills, mixing up the terrain on which you’re running or running with a partner or in a group.

If you haven’t tried trail running, this is an excellent way to add variety (and even motivation) to your training. Check out our post about trail running vs. road running to see more details. This variety helps to make the miles go faster, helps you to enjoy running more, and makes time pass quicker. Listening to music or podcasts while you run can also help to keep you both motivated and entertained on your runs and help you to go further or faster.

Some inspiration from Livestrong in this section.

Can You Run On An Empty Stomach?

You can run on an empty stomach, as your body will use its own fat stores first to give you energy.

More specifically, your body can burn fat stores on an empty stomach after depleting the stored glycogen levels.

It is a common myth that running on an empty stomach will make you lose muscle; though this is possible, your body will only start breaking down amino acids in your muscles after it has gone through the glycogen and energy in fat, by which point you would have had to be running for a long time and will most likely feel dizzy or lightheaded already.

However, for your body to use testosterone in the mornings to build muscle, it is imperative that you follow your run with a protein-rich meal afterward. The cortisol in your body acts as a depressant and is also highest in the mornings, and this could cancel out the positive effect that testosterone can have in muscle-building if the process is not helped with some extra protein. Side note, running releases endorphins, which make you happier, and override the cortisol levels in the mornings, which will likely leave you feeling happier in the morning after a run.

Why Timing Is Important

In terms of when you eat and when you run, this depends very much on what you eat. The basics go something like this: After eating, the body requires energy to be used for digesting food and directs blood flow to your internal organs to facilitate this process. This means that less blood flow is available for muscles and other parts of the body.

So if you decide to go running while your body is still digesting food, blood flow is redirected from your internal organs to your muscles to help you to move. This can result in cramps or indigestion, as your body doesn’t have the energy to effectively run both processes simultaneously.

Inspired from runnersworld

What you eat

Now that you understand this process, you understand why you need to wait after eating before you run and that how long you wait depends on what you’ve eaten. If you have eaten a large meal, then waiting three to four hours is advisable. If you have just had a light snack or small meal, then anything from thirty minutes to two hours will be sufficient. 

This comes down to the content of what you have eaten. Simple carbohydrates, such as a banana and a piece of toast with jam or a muffin, are digested quickly, and an hour should be enough time for this. If you’ve eaten protein, then you will need to wait a little longer. Of course, how long you’re running will also impact how much you eat beforehand, and some endurance runners also train their bodies to process fuel during a run.

Not only is what you eat and how long you eat before a run important, but it’s also important after a run too! For example, if you prefer to eat after a morning run or to run before dinner in the evening, it is important to know how best to replenish your body with fuel—eating something soon after a run is a good idea to replace your glycogen stores and electrolytes and also to stimulate muscle recovery. Aiming for a 3:1 carbohydrate to protein ratio somewhere between thirty and sixty minutes after your run is a good rule of thumb.

Can You Run Two Days In A Row?

Running two days in a row or more is totally possible if your fitness level and motivation allow for it! However, rest is important. If you are just starting out with your running, then having rest days in between your runs is a good idea to get your body used to a new routine while you build up fitness to avoid injury.

If you already have a reasonably good level of fitness, you might be running four or more times a week, in which case a rest day between each training session is not possible. If you are running more regularly, provided you’ve built up your fitness over time, your body can probably handle it.

However, it is important that you don’t push yourself to your maximum every run that you do.

A good strategy is to mix up your running schedule with a combination of longer runs (or runs where you push yourself harder) and shorter runs (or runs where you go at a slower pace). This strategy is a good way to add variety to your training program so that your body has some recovery time, even if your body is still working hard.

Conclusion

There are pros and cons to running at all times of the day. While your body is optimally geared towards running from mid to late afternoon to early evening, ultimately, you need to pick a time that works best for you – for your schedule, and for the mental and physical benefits that you want to get from running at different times of the day.

Whichever time you choose, it will always be a good thing, even if it is a harder time of the day to run – you can’t go too far wrong as long as you lace up and get out the front door!