When Is the Best Time Of Day To Train?

Are You Missing Out On Gains?

By kevin masson • Published Sep, 21, 2019

When it comes to strength training, you have probably heard multiple theories as to what the best time of day to train is. Some folks are positive that their approach is the best, while others don’t really make a distinction, instead working out whenever is most convenient for them, and before we even get into the science of it, if you have a busy schedule and you do not have the luxury of choosing when to workout, let me tell you that any workout beats no workout. This topic is for the slightly more advanced lifters or the ones that love biohacking and get the most out of their body the natural way. Let’s begin!

The question revolves around the states and hormone levels that your body goes through during its 24-hour cycle, or circadian rhythm, which will often dictate the value that you will get out of your workout session. This means that it’s certainly possible to work out at any point in the day and get some benefit out of it, but in order to get the most out of each session, you will have to plan ahead.

There’s quite a bit of science at play, and the effects of lifting weights in relation to our circadian rhythm have been studied numerous times. The trick is to create an optimal workout schedule and attune it to your circadian rhythm. Not only will this help you get in shape more rapidly and become stronger, but it is also likely to increase your muscle gain. You might even be less prone to injury while training during certain times of the day. These are only some of the reasons why it’s important for you to pay more attention to when you work out. In this article, we’ll take a look at some of the science behind this issue and cover a few pros and cons of working out during the three main times of the day.

The Hormones

So, what is the circadian rhythm and what does it have to do with anything? In the simplest terms, the circadian rhythm is a 24-hour cycle of all the biological activity going on in your body. One aspect of this cycle, for instance, is your sleep-wake cycle. The circadian rhythm, especially when mentioned in discussions about sleep, is often also described as your “internal clock.” This is an apt description, as a healthy circadian rhythm does indeed function as a sort of clock; depending on light and darkness and triggering specific internal processes at particular times of day and night.

Because of its relation to daylight and darkness, your circadian rhythm can be disrupted and adjusted by your lifestyle. The circadian rhythm is the most normal in the average person who tends to sleep between 11 PM and 7 AM. For the rest of this article, we will assume that you too practice this average sleep-wake cycle. Apart from sleep, your circadian rhythm regulates three other factors that are important for any kind of training. These factors include your body temperature, energy metabolism, and levels of relevant hormones like testosterone and cortisol.

As you may or may not know, the ratio between your testosterone and cortisol levels is an important factor to consider when building muscle. Testosterone bolsters anabolism in your body, which is essentially the process of building muscle from protein and other nutrients. On the other hand, cortisol, which is a stress hormone, has the opposite, catabolic effect. This is because one of cortisol’s properties is that it assists in the regulation of your blood sugar by breaking down your muscle tissue. In essence, testosterone improves anabolism in your muscle tissue and helps you grow while cortisol causes catabolism and inhibits that growth.

Putting aside ways in which the levels of these hormones can be altered intentionally and strategically, it’s important to understand that they also naturally oscillate in the course of your circadian cycle. Your body’s production of testosterone tends to pick up in the evening and at night. This leads to a high testosterone level early in the morning, which then gradually decreases into the late afternoon before its production picks up again. Cortisol acts differently in that it’s also high when you wake up but decreases all throughout the day, but its production is low during the night. On top of all that, keep in mind that exercise causes an increase in both of these hormones to varying degrees at different times of the day.

As evident from this information and as demonstrated in numerous studies, the sought-after, high testosterone-cortisol ratio is the most pronounced in the afternoon and evening hours, assuming that your circadian rhythm is on point. This was found in a 2004 study by the Australian Charles Sturt University, a 2013 multinational study by Australian and Scottish researchers, and in other instances. What’s also interesting is that these hours of the cycle appear to be the time when intense exercise produces the lowest amount of cortisol and the highest levels of testosterone, which is perfect for strength training.

All of that means that your workout session will have a natural advantage which will, in turn, be amplified by the exercise itself. This desirable hormonal ratio and your body’s reaction to exercise are major advantages to evening workouts. On top of that, it’s also possible that the decrease in cortisol after the workout spike will be faster late in the day, which means your body will suffer less long-term stress after working out. While we’re still unsure as to how exactly these hormonal fluctuations affect muscle growth, the strong correlation is there. As such, reliance on high testosterone levels is a widely accepted approach to muscle building.

Other Factors

As mentioned though, there are numerous other factors to consider. One of the most important things to consider is your core body temperature, which is the temperature of your central organs. Just like your hormones, the core body temperature also goes up and down through your 24-hour cycle. With a healthy circadian rhythm, your core body temperature should reach its lowest point during the night, begin to rise rapidly when you wake up and reach its highest value in the evening.

As it happens, studies such as the one conducted at the University of the West of Scotland’s Department of Exercise and Sports Science have found that a high core body temperature improves our metabolism, muscular blood flow, joint mobility, and much else. These things are, of course, all important for strength training since you will be at your strongest and most flexible stage when your core body temperature is at its highest level.

The slight but numerous variations among people whose circadian rhythms fall in the range of normalcy can certainly be an important factor in deciding when your performance will be the best. You should try and understand your rhythm as well as you can be keeping track of parameters such as your body temperature. Something else that’s always significant is age. Older people generally tend to enter their window of peak performance sooner than younger folks. This is generally true both for hormone levels and core body temperature.

Finally, it’s worth reiterating that cortisol is a stress hormone. External stressors in your life can throw your hormones off balance and bring the cortisol up significantly. Prolonged stress can thus ruin your testosterone-cortisol ratio and severely impede on your workout performance. The time of day when you decide to lift will matter much less if your hormones are chronically unbalanced. You should try to be less stressed out at least during one period in your day when you work out. Having successful workout sessions and great performance can alleviate your stress levels outside of just your exercise, which is a major reason why many folks exercise in the first place.

When To Actually Work Out

And so, the dilemma is usually the simple question of morning versus late in the day. Based on most of what you’ve just read, a late afternoon or evening lifting session seems to be a no-brainer. However, things aren’t always that simple.

First of all, not everyone’s circadian rhythm is the same, and yours might be inconsistent or just significantly off base. If you want to follow the programs and advice that apply to regular folks, it might be best to first get your internal clock in order. Sleep is crucial if you want greater gains. Adjusting your circadian rhythm to “normal” isn’t just about making it easier to use advice, though. Consistency and regularity are the best friends of a productive workout routine.

With that said, research does seem to suggest that working out, particularly via strength training, will provide the best performance in the early to late evening. Being at your strongest phase during this time will allow you to work out longer and get more out of each session while peaking anabolically.

Among the studies that have looked into workout performance in the evening versus the morning, most of them have reached conclusions in favor of the evening. For instance, a 2016 study conducted by a team of experts from Europe, the US, and Australia, led by Finnish experts from the University of Jyvaskyla, used two groups for their research. Both groups engaged in both strength and endurance training for a period of 24 weeks, but at different times of the day. The morning group worked out between 6:30 and 10 AM, while the evening group did so from 4:30 to 8 PM. The differences in overall performance weren’t too striking, but the evening group did show a greater increase in muscle mass. This is huge if your goal is to indeed put on more lean body mass.

An Indian team of researchers in New Delhi had published similar results some two years prior in the Indian Journal of Physiotherapy and Occupational Therapy. These researchers focused on differences between eccentric and concentric training as well, and they found the best possible results with eccentric exercise regimens in the early evening. As you may, know eccentric time under tension has been shown to have a great micro-damage on muscle tissue, which in turn leads to greater gains with recovery.

At any rate, we’ll need quite a bit more research to truly understand what’s at play and how to make the most of our internal processes, but the effect of our circadian rhythms on workout performance and muscle growth is all but apparent. This means that the correlations are strong, but the causal relationship is yet to be proven beyond any doubt. In all, late afternoon and evening hours tend to be the best option for weightlifting in most cases, but not always. We’ll take a look at some more factors that should help you decide.

Morning Vs Afternoon & Evening

As you can see, while there are strong indications that the evening tends to be a peak-performance period for most people, nothing is exactly final or clear-cut. There are more factors and parameters to consider in how your body functions in the morning and evening, so let’s take a look at some additional pros and cons.

Some of the clearest advantages or pros of mornings are the high testosterone levels and high alertness. We already discussed the anabolic properties of testosterone, but being alert and highly focused also has many benefits and can make you more efficient. As you might have deduced by now, working out in the morning will mean that you’re exercising with high testosterone and little to no food in your system. This could potentially impact your strength or at least your strength-endurance as you are more likely to deplete your glycogen stores. While most people tend to be highly alert in the morning, a workout session can make them even more focused and energetic, which is another benefit to such a routine. Over time, morning exercise can lead to an overall improvement in mood as well, which is why many folks do it.

One of the most immediate and obvious cons of morning weight training is that it will require you to wake up earlier, which requires planning if you are to avoid having to rush to work, miss breakfast, or lose sleep. Of course, working out in the morning can make you miss out on your peak-performance hours if you decide to stick to just this one daily session or if you are too tired to exercise in the evening.

The early afternoon is usually the period when we are the least active, while the following hours tend to be a general crossover between the morning and evening when it comes to all those important factors we discussed. This is why the afternoon is a real sweet spot for many people. It also happens to be the time when your pain tolerance is the highest, which can motivate you to push a bit further than you would otherwise. As for the evening hours, you’re now acquainted with most of the pros, but, despite everything, there are certainly cons as well.

First and foremost, evening exercise, in general, has the potential to interfere with your sleep. The later and more intense the exercise is, the higher the chance of sleep interference becomes and, of course, strength training is one of the most intense exercises out there. Add pre-workout or another stimulant to that and you can kiss goodbye to a goodnight rest. Even if you tell yourself it doesn’t impact you, it does. Your heartrate will stay elevated longer and your overall time under REM sleep (deep sleep where recovery happens) is drastically impacted.

Another potential problem has to do with motivation, as a long and hard day can completely change your perspective by the time your gym plans come around. Sometimes, it can feel next to impossible to hit the gym after everything you’ve had to put up with at work and elsewhere. As such, evening workouts perhaps have the greatest skip potential of all the options, and this can be a real problem if you already struggle to stay motivated. Because of everything we’ve discussed and because of the work schedules of most people, gyms tend to be the most packed in the later afternoon and evening hours, which is always a con if you don’t have many options where you live.

All told, lifting weights in the afternoon can definitely come recommended, but it’s hardly ever a necessity. All of the positive effects that we’ve discussed can vary a great deal from one individual to the next and they are often not worth the hassle and the stress if training in the evening means you have to go out of your way to make it to the gym. Trying to strike the perfect moment is a good idea, but it’s especially important to listen to your body. The small percentage increase in performance can end up completely overshadowed by your exhaustion, lack of motivation, schedule-induced stress.

Take-Away Points

Morning

Pros: Greater mental focus and motivation, good for muscle building due to morning testosterone peak.
Cons: May impact sleeping time due to waking up earlier, may also impact overall training time if nutrition is not on point.

Afternoon/ Evening

Pros: Best potential for breaking plateaus because pain threshold is highest and the limits of the body might be able to be pushed further than usual.

Strongest performance as this is the time of day when the body is in peak condition for physical activity.

Overall creates greater muscle gains due to adding second testosterone peak during the day.

Cons: Lack of motivation after a busy day. If training is in late evening this will drastically impact sleep quality and potentially negatively impact recovery.

Conclusion

What you have to focus on is consistency, a healthy and strong diet, and getting enough quality sleep. New research will give us more information in time, but, as of right now, the things I just listed are likely to have the strongest impact on your workout performance and muscle gain. Keep in mind that early birds and night owls are indeed a real thing as well. Instead of forcing things, you should adapt your training regimen to fit in as well as possible with work, leisure, and sleep before making adjustments to try and make the absolute most of your unique circadian rhythm.