When Is The Best Time To Exercise?

by Kevin Richardson

Everyone has their preferences and ideas as to when is the best time to exercise. Some like training first thing in the morning and starting the day with a good workout, others squeeze in their training sessions around lunchtime while most tend to train after work in the late evening or at night. The question remains however when is the best time to train and does the time that you train really matter in the first place?

Unfortunately, the answer isn’t as clear cut as one might expect as there is no real best time to exercise per se- only times that may be ideal based on your individual training habits. While the science of how our body works indicates that late afternoon workouts are usually best for optimum performance, the adaptive nature of our bodies are such that we can learn to operate at peak efficiencies at almost any time of the day by training ourselves to do so. In this article we will take a hard look at the pros and cons to training at different times of the day and hopefully it provide some insight into the best training times for you.

When Is The Best Time To Exercise- A Look At How Our Body Works

Your body works in accordance with what are called circadian rhythms which are in a sense very much like an internal clock that operate on a cycle of just about twenty four hours.[1] Fluctuations in our core body temperature occur in conjunction with the passage of the day- rising and falling between approximately 97.5 and 99.5 degrees Fahrenheit- (that’s 36.5 to 37.5 degrees Celsius for those of us on the metric system).

Our inner body clock is designed in such a way that it resets itself every day using light as a major frame of reference. It synchronizes both our moods and energy levels in a cyclical pattern based on what the time of day it is- a phenomenon that we all can easily relate to in our everyday life . for example, when you wake up your mental performance isn’t quite as sharp as it is after you have been awake for a couple of hours- regardless of how much coffee you drink!

 It takes time for us to ‘warm up’ and it is a process that happens gradually over time as we get sharper and sharper as the hours go by. This increase in mental acuity continues up to the early evening, at which point our ability to concentrate begins to decline. This pattern holds true not just for our mental capacities but for everything from peak muscular performance, anaerobic power output and our overall motivation to exercise in the first place.

So When Is The Best Time To Exercise?

From a strictly statistical perspective the human body under normal circumstances is at its physical best from 4 pm to 7 pm.

This may sound like a very clear cut answer to the question of when is the best time to exercise- but it isn’t. While it is true that our hormone levels peak in late afternoon thus giving our muscles peak potential in terms of flexibility and power output, the increase in performance in a real world setting is very slight. You see, being the ever adaptive beings that we are, you can train yourself to perform at your best at any time.

Several studies have found that when individuals are made to train only in the morning or only in the early evening (our theoretical peak time)  those that trained in the morning did better as a whole on physical performance tests early in the day while the evening trainers did better on their tests in the evening.[2] The same pattern applies to athletes as well as studies have shown that changes in time zones and time of performance significantly affects the outcomes of sporting events.[3,4]

When Is The Best Time To Exercise? Anytime!

Exercise, like light and change in environmental temperature seems to also have a powerful effect on synchronizing our internal clock.[5] So how does this apply to your training? Well if you have an event that will require you to be at your best, it would make sense that you time your training to coincide with the time of the event several weeks beforehand. Other than that, even though research shows that the ideal time to exercise is in the late afternoon, the advantages are slight and at the end of the day you will adapt anyway to whatever time you train.

From personal experience, I have trained both on morning and in the evenings (I do my leg workouts on Sunday mornings and the rest of my body during the week at around 6:30 pm or so as I have for the past ten years or so). Do I see any noticeable difference? Not at all, and with the poundages that I lift and the degree of intensity with which I train, any drop in performance would be very easy to detect! The same applies for the hundreds of people I have trained over the years as well- although well over 95% of them do prefer to train in the evening.

Is there a difference in the amount of body fat lost from training in the morning versus training in the evening? Again, my experience working with a large number of  clients hasn’t shown any difference nor is there any real science behind the idea of the morning being the best time to exercise in terms of losing body fat.

Practicality has to be taken into consideration before anything else so if you are only able to train on mornings, then that’s when you should train- if you find it more convenient to train on evenings- then that’s your ideal time to exercise. The key to success in any athletic endeavor or fitness program is consistency- so find a time to exercise that fits into your life in such a way that you can stick with it and you’ll always be successful!

References:

1. Charles A. Czeisler MD, PhD (1999). “Human Biological Clock Set Back an Hour”. Harvard Gazette 1999

2.  Atkinson G, Reilly T. Circadian variation in sports performance.Sports Med. 1996 Apr;21(4):292-312.

3. Smith RS, Guilleminault C, Efron B. Circadian rhythms and enhanced athletic performance in the National Football League. Sleep. 1997

4. Winter WC, Hammond WR, Green NH, Zhang Z, Bliwise DL. Measuring circadian advantage in Major League Baseball: a 10-year retrospective study. Int J Sports Physiol Perform. 2009

5. Reilly T. Human circadian rhythms and exercise. Crit Rev Biomed Eng. 1990