People often ask me what time of day is ideal for training. This is usually because they are curious as to when they can burn the most calories or get the absolute most out of their fitness. The answer, to me, is not simple. It involves physiological and lifestyle aspects combined. Bodybuilding.com recently had a competition for people to write in and address some of these issues, and I really liked a few of the points that the writers made. I will attempt to lay out an outline below using some of these comments as well as my own thoughts.
To begin, let’s start with the physiological components that play a role in this debate. For this, we visit the endocrine system. There are 3 main hormones that play a vital role in this issue. They are: Cortisol, Growth Hormone, Testosterone.
This is produced in response to stress and low blood-glucose concentration (don’t confuse this with Cortisone). For the general discussion on this topic, it is a bad hormone, and we don’t want it (it is necessary in the body for other things). It promotes fat storage and muscle breakdown, while reducing bone formation. Cortisol levels are highest during the first 2 hours after you wake up, and decrease gradually after that. However, this isn’t a problem because, during your workout, your cortisol levels will spike anyways.
Growth hormone (HGH in people), is not based on time of day, but instead, how many hours you sleep every day. Growth hormone promotes muscle growth, so getting a good long night sleep will certainly help. Effects of growth hormone are typically described as anabolic, or building up. When children grow suddenly, it is the effects of HGH.
Testosterone is the principle male sex hormone, but is also produced in the ovaries of females. It is responsible for bone density, bone maturation, and muscle mass production, which is why steroids work so well. Testosterone levels peak in the morning, which means it is best to workout in the morning for both fat loss and muscle building.
Next, let’s look at two important parts of physical fitness.
STRENGTH & FLEXIBILITY:
More strength for lifting means more muscle stimulation, which means more growth. As a result, your strength levels are an important factor if you want to build muscle, considerably less if you want to lose fat.
Flexibility is also important for muscle building because more flexibility means less chance of injury and larger range of motion, which both mean more muscle mass. Flexibility is less important for burning fat. Strength and flexibility peak during the late afternoon.
Athletes seem to perform best in the late afternoon, when strength, body temperature and flexibility peak.
Now, we address the time of day when one might workout.
Morning – Best potential for building muscle because testosterone is critical in protein synthesis and for rebuilding muscle fiber damaged in weight training. There is also greater mental focus, which may allow for greater mind-muscle connection and greater efficiency of muscle work done. Morning exercise may help in reaching this goal partly due to higher than normal testosterone. It also helps that your body has not had much food to process yet, and may turn to fat for energy instead. Exercise has shown to increase serotonin levels. Low serotonin has been shown to be related to depression. Exercising in the morning could possibly help elevate mood slightly for the rest of the day.
Afternoon – Best potential for breaking plateaus by employing muscle shocking techniques because pain threshold is highest and the limits of the body might be able to be pushed further than usual. This time of the day is a good balance between all the issues discussed in both morning and evening sections.
Evening – Best potential for strongest performance. This is the time of day when the body is in peak condition for physical activity. Working out increases ability to absorb nutrients on a cellular level. If adequate nutrition is not in place after a workout, the body might soon be left hanging for an eight hour fast while you sleep.
Conclusion (possibly): weight training is best in the afternoon based simply on strength components.
In this same article on bodybuilding.com one of the writers refered to morning people as “larks”, and afternoon/evening people as “owls”. I like these terms, so that’s what we’ll use here.
LARKS VS. OWLS:
There are some that rise from sleep earlier. They wake up enthusiastic and full of energy. Such people are called “larks.” Another type of person, the “owls,” wake later and more slowly than others, taking a few hours to get functioning and feel alert. Generally speaking, the owl will perform better in the late afternoon, while the lark will perform better in the morning.
Both these types of people actually form a minority, though. Most people, about 60% to 70% of the population, are indifferent. This means they fall somewhere in between the lark and the owl.
By doing a workout in the morning, it will be out of the way, out of mind. There will be less worry about missing a workout and less stress in anticipation of your performance if it gets done sooner in the day. It can set the tone of your day, giving you a positive feeling of accomplishment before you really even begin your day. If your workout is done early in the day, other events that may come up suddenly for work or family, will not effect your training, as it’s already out of the way.
The pro’s are that is you are an “owl” you are more awake and alert during this time of day. A morning workout could be useless because you’re just not awake enough yet, so the effort is a lot less. Typically, afternoon or evening group exercise classes are bigger since more people prefer to sleep in or can’t make the early am’s due to their schedule. This may be a pro for you, if you like a big group to get you motivated, or it could be a negative if there is limited equipment and other people slow you down. If you are working out too late, this can affect your body’s natural time of slowing things down for sleep. Another con is that if you feel tired or drained after work you are more likely to skip an afternoon/evening workout. How worn out you get from school, work, or other daily activities play a role in your evening weight training efforts.
Is it a good idea to switch between morning, afternoons, and evenings? Alternating, according to many people, is not a super idea. This is due to the body tending to prefer routine. Digestive habits may be on a certain cycle for some people and messing with your natural system may throw you off. For long term fitness program adherence, sticking with a daily routine has proven the best route.
For me, I consider the “lifestyle” factors more important than the physiological factors. It’s important to be disciplined so that when your motivation dies, you still carry on with your workouts. Whatever time of day works best for you and keeps you coming back, stick with that.