I get a lot of flack for training before or as the sun is rising. I don't see a need to defend myself, but I will explain why I subject myself to what seems like a terrible experiment to most. First let me say I haven't always been this way, I used to train after work, but then I met my training partner and decided to switch to mornings for camaraderie (I am glad I did because my training partner rocks). It took me several weeks to adapt to the early morning routine--but I did--and I realized that it has a lot of merit. Here's why:
Avoid schedule and time constraints. It's hard to predict what the afternoon will bring. Sometimes work will keep you longer than expected, things come up, and schedules change throughout the day. Consistency is an important aspect to training, especially if your diet and caloric intake corresponds with certain workouts. If afternoon constraints can be an issue then the morning is a great alternative because chances are you have nothing to do but sleep in the morning (which you could be doing at night).
Beat the crowds. Ever have to wait for a squat rack because someone is doing curls? The morning is the best time to avoid crowds, idiots, and mirror-muscle lifters.
Low stress and higher energy. After a day of work stress can compile and whether you realize it or not it can effect your workout. Also, after you have been awake for at least 8 or more hours your energy level starts to decrease significantly, and energy is key in the gym. In the morning, after eating breakfast and warming up, energy levels are at their highest and stress is at it's lowest.
Optimal hormone levels. Cortisol levels peak mid-day and are on a slope in the afternoon and the morning, so as far as cortisol goes, training time doesn't matter unless you train in the middle of the day. Testosterone levels are a different story. Testosterone peaks early in the morning and slowly drops off during the day, making the morning the best time to train. Glucagon levels are highest and insulin the lowest first thing in the morning after the body has been fasted overnight. Since the body has been deprived of insulin throughout the night, it has the highest response to insulin first thing in the morning. You're medium to high carb pre-workout meal (breakfast) will boost your insulin levels more than any other meal of the day and this will prime you for a great workout.
Like everything, there are drawbacks to training early in the morning. Nutrient timing can become tricky. You have to decide whether to up your carbs the night or day prior to training (which most people are uncomfortable with for fear of fat gain) or the entire day after training. I have personally found that upping carbs the day before is the trick to increasing my strength and endurance in a morning training session. While upping carbs the meal after working out, but not the entire day after working out helps with recovery. Do I gain more fat than the afternoon lifter because I up my carbs at night two or three times a week? Perhaps, but I am not sure. Another major drawback to training in the morning is that for most, it takes a while to wake up, eat, and warm-up at the gym, which subtracts more from your sleep. While going to the gym in the morning helps avoid scheduling constraints that might come up at the end of the day, it's also impossible to predict how well you are going to sleep. When I have a bad night sleep or something keeps me up later than I expected then I have to reschedule my gym day or go into work late (which I do not want to do very often). When it comes to hormone levels and beating crowds, it's hard to argue that there is a better time to go to the gym. Working out early may not be your cup of tea, but remember that the early bird gets jacked.
Posted by Seth Carbonneau