Many runners ask me this question every year. I usually respond, “When do you run?” They usually tell me, “I like to run in the morning.” I respond, “Then you should run in the morning.” Every runner has a different perspective on their running time and there are many different factors that play into it. Factors like children, work, sleep and spouses can all affect when people run. I am going to look at running times in a scientific way. Once you’ve read my argument, you can decide which is best for you.
Your body is definitely not at its peak in the morning. Your body usually has a low core temperature, which means your muscles will feel stiff, your lung function is low and you probably have not eaten in about seven to nine hours, so your energy levels are low. This means your body will need to work harder to get through the workout. Working through these runs will actually help you to develop your mental strength.
This is the most popular time to run, maybe because people like to forget about work for a while. The funny part about running at this time is that it actually helps your work performance more than your running performance. Running at this time wakes the body and mind up. You can actually be more productive in the afternoon after a lunch-time run. However, all body functions usually hit a lull in the middle of the day, which again causes your body temperature and lung function to become low.
Research has shown that your body is at it peak performance levels during the late afternoon or early evening time. Body temperature peaks at this time, and your muscles are fully warm and ready for speeds that are hard to reach in the morning. Your lung function is more than six percent better in the later afternoon than at any other time of day.
Physically, there aren’t any “bad” times of the day to run. Many of the issues surrounding when to run are psychological. Some runners say they are mentally drained at the end of the day. However, physically, that is the best time to run. Some runners feel mentally refreshed in the morning, but research has shown it to be, physically, the worst time to run.