I always practiced sports, the most traditional (football, cycling), even the most different (boxing, hockey) ... But in recent years has been my greatest dedication to weight lifting, and according to the studies and work, each day I have more less time to train. I trained from 23 hours to 24 hours (midnight), many friends prefer to train in the morning, before work and so forth, and say the result is better, never knew that answer, because I feel more available the night ... But I did a search and discovered that the second Jennifer Ackerman, author of Fri Sleep Eat Drink Dream, which is a guide that teaches people to live in accordance with the body's clock, the time that the body is at its maximum is between 15h and 20h, when our body temperature is higher, the joints are more flexible, more open the airways and the heart is pumping more effectively. So if you have this free time practicing some exercise that band, as in the case of weight lifting can be a gain of muscle mass 20% larger than if the training is practiced in the morning.
Good training!