Timing of exercise – does it matter when you exercise?
The answer is more complicated then it seems. Our days are driven by what is called circadian rhythm. This means that we have a tendency to either be early risers or night owls by nature. The first school of thought in regards to timing of exercise, is that we should follow our circadian rhythm. By exercising when we are naturally at our most energetic, we will tend to be more consistent with the routine. For instance, if you are not an early riser and you try to wake up every morning to exercise you will not perform at your highest and you will tend to give up on that routine.
Studies do however show that it does seem to matter what time of day you exercise depending on what your overall fitness goals are. Studies have shown that the most effective time to exercise in order to lose weight, is actually within 30 to 60 minutes of waking up. After fasting the entire night while sleeping, your glycogen stores (which is your stored sugar) are low. Thus, you will burn through them faster and get to burning fat. Studies also showed that those individuals that worked out in the morning tended to be more consistent with exercise. Likely because they got their exercise routine out of the way early and didn’t find excuses or lack of time throughout the day.
If building muscle (even lean muscle) is your goal, then exercising in the late afternoon/early evening tends to be better. Testosterone levels rise at this time of day and basal body temperature is elevated as well. Both of these factors allow for more strength and endurance during exercise.
My recommendation, find the time of day that you will be most consistent with. No matter what is happening with your testosterone levels, basal body temperature, or glycogen stores, if you aren’t going to consistently exercise just because it’s not the best time of day for you, then you are not going to reach your fitness goals!