Morning Run or Night Run?

Running is a versatile sport in that it can be a way to manage stress, improve overall health, and can be a way to satisfy one's competitive edge. Running is also an activity that does not require much equipment and many love the sport for the ease of in which it can be done, practically anytime and anywhere. So when is the best time to run? Does running in the morning or evening differ in benefits? Can either or be riskier? We investigate the answers to these questions and more about morning versus night runs and the pros and cons of each.

Many morning runners will claim they are free from the hustle and bustle of the outside world, that a morning run is a great way to boost energy levels, that they are less stressed throughout the day, and, for many, it is the only time of day they have free to balance an exercise program with work, family, and life. While at the same time, evening runners will boast that their energy levels are higher later in the day resulting in overall better performance. They too may also claim it is the only time in the day that fits exercise into their schedule. 

To be or not to be a morning or night runner: 

It can be assumed that most people will pick the time of day to run that suits them and their schedule the best. Additionally, environmental factors may play a role as in the weather, traffic, or safety measures in regards to lighting and personal protection. You could ask a hundred different people whether they would prefer to run in the morning or at night and you'll probably find that the responses are evenly split. There are many subjective factors in why someone would prefer to run in the morning versus at night but that doesn't necessarily mean one time is better than the other. So we turn to science to see if there are positive or negative health benefits in the comparison between the two times of the day.

For example, this 2016 Study from the Journal of Human Kinetics looked at several athletes chronotypes or their circadian rhythm, otherwise known as a person's innate activity of when they are most alert and the preferred time of day of when to sleep, and whether that played a role in the time of day they participated in their sport. Their findings were that morning people preferred to do sports in the morning. In summary, sleep/wake cycles and energy levels ultimately determine when you will choose to run. 

Tell me more about Morning Run Benefits:

This 2014 Study out of Vascular Health and Risk Management found that people who regularly participated in a moderate aerobic activity at 7:00 in the morning had overall improved daily systolic blood pressure regulation and improved quality of sleep. This means for some individuals that running in the morning could be an alternative to pharmacological treatments for high blood pressure and sleep irregularities. 

But the cons:

Unfortunately, this 2010 Study from the European Journal of Applied Physiology determined that upon waking blood pressure is higher and morning exercise could lead to potential risks of heart attacks and strokes amongst those with underlying conditions. 

And now for the Night Run Benefits:

This 2019 Study from the European Journal of Applied Physiology tested male endurance runners in three different groups 1) high-intensity workout, 2) long endurance run, and 3) no exercise at all 3.5 hours before going to bed to determine if running interrupted sleep. The results found neither high intensity and low-intensity workouts negatively affected sleep and, in fact, positively improved sleep behaviors. 

In regards to performance, this Trial for the International Journal of Sports Medicine tested the timing of elite class male runners on 80m short distance sprints multiple times a day over 5 days. The peak performance always occurred between 17:00 and 21:00 h. Thus, evenings tend to provide the optimal timeframe for high performance. 

However...

While this 2020 Study from Scientific Reports concurs with the previous study that peak performance in natural environments does occur in the evening, the study also found that adapted mornings where the environment was hot, adequate warm-up occurred, the athlete practiced intermittent fasting, and if the activity was regularly practiced in the morning that peak performance could also be achieved in the morning. This essentially means humans can adapt so there is no need to change the time of day you decide to run to reach peak performance. 

Additionally, in regards to weight management, this 2014 Study form the Journal of the International Society of Sports Nutrition found there was no difference in body fat loss and body change composition based on if an individual had fasted or not previously to aerobic exercise. Meaning, if you would like to exercise in the morning fasted or later in the evening after having had fuel, the results of body fat loss will occur positively with exercise either way.   

So is running at one time of the day better than the other? 

Not really. A 2019 Randomized Controlled Trial sought to determine if morning or evening workouts factored in adherence and physiological adaptations for overweight adults in a 12-week intervention. The results found that morning workouts had a slightly higher adherence (94%) compared to (87%) for the evening group. However, the health benefits of cardiovascular and respiratory fitness improved for both the morning and evening groups. 

So in conclusion, running can provide many positive health benefits for you both physically and mentally regardless of the time of day you choose to go for your run. The decision to run in the morning versus the night is mostly based on feel and schedule. Positive physiological changes such as weight loss, lowering blood pressure, and improving sleep quality will occur with both morning and night runs as long as you are consistent.

So, are you a diehard morning runner or night runner? Or do you run when you can? According to science, there is no right or wrong time to run!