Having a hard time mustering up the energy to get a workout in? I know it sounds strange but exercising gives you more energy! The more you do, the more you will feel like doing. Barring any medical issues, or being tired due to working out too much, you should get that activity in even if you would much rather crash on the couch.
One study looked at healthy, sedentary people who began exercising three days a week for just 20 minutes a day at either moderate or low intensity. By the end of six weeks, their energy levels were 20 percent higher than those of a control group of non exercisers. Exercise scientists attribute this to an increase in hormones like adrenaline which allow you to have more blood flowing to your large muscle groups and tells your body to ignore feelings of fatigue.
I've talked about the many, many benefits of regular exercise before. Here is yet another reason to get moving at least a few times a week. It will give you more energy!