Everyone has workout schedule preferences, and many have various theories as to why they think their schedule is best.
Some of us like to wake up early and start our day with working out, whereas others prefer to train later in the afternoon or in the evening.
Are certain times better than others for building muscle, though? Is the time of day that we train important at all?
Let’s find out!
Generally speaking, most people are weakest in the morning, and strongest in the late afternoon and evening.
One study found that maximal power output during cycling sprints was higher in the early afternoon than the morning. Another cycling study found that power output was about 6% higher at 6 PM than it was at 6 AM.
These effects have been seen with weightlifting as well.
Research conducted by The College of William & Mary looked at the time-of-day effect on training with ten healthy, untrained men. Subjects performed strength tests at 8 AM, 12 PM, 4 PM, and 8 PM, and force production was greatest in the evening.
Other studies demonstrated similar findings. Research conducted by the University of Bourgogne found that subjects’ non-dominant quadriceps were strongest at 6 PM. A study conducted by the University of Jyväskylä showed that peak leg torque was lower at 7 AM than 5 PM.
The bottom line is if you do your strength training in the late afternoon or early evening, you’ll probably perform a little better than the early morning.
It’s worth noting, however, that using caffeine before your early morning training can boost your performance to afternoon levels.
Furthermore, research has shown that if you consistently train at a certain time of the day, your body will eventually adapt and perform best at that time.
Personally, I like to train early in the morning, even if I’m a tad weaker than I would be training later in the day. The weights are completely free at 7 AM, and I get a huge energy and mood boost that lasts the entire day. And I’ve never had trouble making gains on this schedule.
Some people hear that testosterone peaks in the morning and drops at the end of the day, and worry that training in a lower-T environment could be problematic.
Well, while it’s true that testosterone reaches its daily low point in the evening, research has shown that the exercise-induced rise in testosterone can actually be greater in the evening than the morning.
There’s also the hormone cortisol to consider, which is released in response to stress, and which is a “catabolic” hormone (meaning it breaks substances down, including muscle and fat).
Resting cortisol levels are highest in the morning, before waking, and progressively decline as the day goes on, reaching a low point in the evening. Research has also shown that the cortisol response to exercise is lower in the early evening (7 PM) than the morning.
Because higher levels of testosterone and lower levels of cortisol means a more anabolic environment, researchers from the Charles Stuart University theorized that the evening may be the optimal time to perform resistance exercise.
How does this theory hold up in practice, though? Will we actually make better gains by training in the evening?
The short answer is probably not.
How can that be, though? Surely more strength and a more anabolic hormone profile must result in more muscle growth, right?
Let’s first talk about the hormone profile. Higher testosterone levels and lower cortisol levels sounds like a recipe for building more muscle.
It’s not though.
Research conducted by McMaster University demonstrated that natural (the key word here) variations in exercise-induced spikes of hormones doesn’t affect–positively or negatively–muscle growth and strength progression.
This is why testosterone boosters, even if they worked (most don’t), are a waste of money if you’re looking to build more muscle. And this is why the relatively small, natural hormonal fluctuations that occur throughout the day aren’t likely to affect much either.
Similarly, small, temporary (remember that your body will adapt to your training time) differences in strength don’t matter much, either.
A study conducted by the University of Jyväskylä lends some insight on the matter. The subjects participated in a 10-week training program, with one group performing their workouts in the morning (between 7 – 9 AM) and another performing their workouts in the afternoon (between 5 – 7 PM).
At the end of the 10 weeks, researchers found no significant difference between the strength and hypertrophy gains between both groups. The morning group gained an average of 2.7% muscle in their quad, and the afternoon group gained an average of 3.5%.
The .8% difference wasn’t enough to register as statistically significant, but it’s possible the difference would have been larger, or smaller, with more people, or longer training.
All things considered, choosing the right workout schedule is like choosing the right dietary protocol: the best one is the one you’re going to stick to.
The bottom line is you can be very flexible with your workout schedule. It is, however, smart to stick to a schedule once decided upon so your body can fully adapt to the training time.