How can I exercise if I am always too tired after work?

Fatigue is one of the main reasons why you might not exercise at all. However, exercise has shown to boost metabolism and re-energize the body. You do not have to do all of your exercising at the end of the day. You can try working out in the morning, at lunch or even through the day. Many employers now encourage walking meetings, so instead of sitting at a desk, why not discuss work initiatives during a walk. Instead of sitting in a lunch room, or at your desk, eat lunch then go for a walk for the remainder of your work hours. 

During the evening hours, instead of watching TV from the couch, do sit-ups and push-ups during commercial breaks. During the show, do lunges and squats to work the legs. If you do this through two TV shows you will be getting a good workout. The bottom line, you can always find ways to add exercise into activities of daily living.