Morning Running vs. Evening Running: Which is Better?

The benefits and drawbacks of morning and evening running are quite distinct, and the choice between them largely depends on individual preferences. Let's analyze the differences between morning and evening runs and determine the most suitable time for running during the day. Ultimately, the best time to run varies from person to person.

To discuss morning and evening running, let's first define the time frames for each. The typical running time frames are early morning (6-7 AM), late afternoon (3-5 PM), and evening (6-8 PM). Keep in mind that the following discussion is based on these time frames. Other time frames will be briefly mentioned later.

It's important to align your exercise routine with your body's circadian rhythm, as different times of the day can impact your running performance. So, let's address some key questions to help clarify the confusion:

Why should you follow your circadian rhythm?
Are mornings or evenings better for running?
Are other times of the day suitable for running?

Why Should You Follow Your Circadian Rhythm?

Running is one of the healthiest activities you can engage in, offering benefits such as weight management, reduced risk of heart disease, and improved cognitive abilities. However, the timing of your run can influence these benefits because your body follows its circadian rhythm or biological clock.

Circadian rhythm is a 24-hour cycle that governs various physiological parameters in your body, including body temperature, hormone levels, respiratory capacity, reaction time, muscle strength, and energy storage. Core body temperature, in particular, plays a significant role in your running performance. Research suggests that running when your core temperature is higher yields several advantages, such as increased blood flow, better oxygen and nutrient delivery to muscles, improved joint lubrication, enhanced endurance and energy levels, reduced risk of injury, increased nerve conduction speed, and improved glycogen and glucose breakdown.

Studies have shown that athletes perform better when their core body temperature is elevated. Therefore, the ideal time for exercise is in the late afternoon to evening, roughly between 5 PM and 8 PM. Now, let's return to the question of morning vs. evening running and delve deeper into the advantages and disadvantages of each.

Morning Running:

From an environmental perspective, early morning running offers quieter outdoor conditions, less traffic, and better air quality. Therefore, the external conditions for morning running are optimal, making it a comfortable choice. Additionally, morning running has two significant advantages: it can effectively lower blood pressure (supported by research) and enhance mood, thanks to the release of endorphins.

However, from a physiological standpoint, early morning is not the most suitable time for running. It contradicts the body's circadian rhythm, as core body temperature and other circadian markers, including lung function, are still at lower levels during this time. Research suggests that various bodily functions, including muscle strength, may not be at their peak in the early morning. Furthermore, early morning runners may face challenges such as inadequate sleep, incomplete digestion of food, reduced muscle strength, and joint stiffness.

Evening Running:

Physiologically, running in the evening aligns better with the circadian rhythm. Core body temperature is still elevated during the evening (6-8 PM), allowing the body to reap the benefits of this natural peak. Studies have shown that the body is in optimal condition for running during this time, with circadian rhythms approaching their daily peaks, especially for lung function, a crucial factor in running performance.

However, psychologically, running in the evening (6-8 PM) can be challenging for many people. This time corresponds to the end of the workday, and fatigue from a full day's work can make it difficult to find the motivation to exercise. From a mental perspective, it may not be the most convenient time because mental alertness tends to decline as the day progresses. Nevertheless, if you can muster the motivation to run during this time, you may find it more enjoyable and potentially experience better training results.

Are Other Times of the Day Suitable for Running?

You might be wondering about running at other times of the day, such as in the morning (9-11 AM), around noon (12-2 PM), or in the early afternoon (2-4 PM), or even later at night (9-11 PM). Here's a brief overview of these options:

Morning (9-11 AM):
Physiologically, this time frame is better than early morning for running. Lung function and core body temperature have improved compared to early morning. To support your morning run, it's advisable to have a meal rich in protein and carbohydrates before running to boost energy levels. Morning running can be suitable for those who can spare time during weekdays or prefer weekend runs. It can also help with muscle development and strength training.

Noon (12-2 PM):
Running at noon is popular in some countries, as it aligns with the lunch break. However, this time frame isn't ideal for running from a physiological perspective, as many circadian markers, including core body temperature and lung function, experience a temporary dip. Nevertheless, if you have limited options and want to maintain a consistent running schedule, a lunchtime run can be accommodated. It may also help improve your afternoon work productivity.

Early Afternoon (2-4 PM):
Similar to the late morning, early afternoon provides better physiological conditions for running compared to early morning. Most circadian markers are at higher levels during this time, including lung function and core body temperature. While not the optimal time, it's a reasonable choice for running, and your muscles and overall body condition should be relatively relaxed. Running in the early afternoon may also positively affect your work performance in the later part of the day.

Late Night (9-11 PM):
Late-night running is a common choice for individuals with busy schedules who can only find time to exercise at night. From an environmental perspective, the conditions for nighttime running are similar to evening running, with quieter streets but potentially poorer air quality. Physiologically, late-night running aligns well with the circadian rhythm, as core body temperature remains elevated. However, it's important to avoid overly long or high-intensity runs in the late evening, as excessive exercise can lead to heightened alertness, making it challenging to fall asleep.

In summary, the best time to run depends on various factors, including your individual preferences, work schedule, and how your body responds to different times of the day. Morning, late afternoon, and evening are all viable options, each with its own set of advantages and disadvantages. Ultimately, the most important thing is to establish a consistent running routine that fits your lifestyle and helps you achieve your fitness goals. Additionally, for nighttime running, it's crucial to prioritize safety by wearing reflective gear, using a flashlight, croc lights, and being aware of your surroundings to ensure a healthy and secure running experience.