On average, we spend more than half of our waking hours sitting down: working at a computer, watching television, traveling in a car, or doing other sedentary things such as reading or chatting with friends. But long stretches of uninterrupted sitting have a range of undesirable effects that may harm your heart, says Captain John.

Here are few tips to keep you moving.

1. Set a timer out of arm's reach. Using your smartphone or a regular kitchen timer, set an alarm to go off every 60 minutes during the day when you tend to sit for long periods of time. Put the device across the room to force yourself to get up to turn it off.

2. Pace or tidy up during phone calls. Whenever you're on the phone, stand up. Try to walk back and forth or in circles while you talk. Or use a hands-free headset and straighten up your office or do some light housework while you chat.

3. Move a little while you watch TV. According to a recent Nielsen report, the average American watches five hours of television a day, and that amount increases as people age. Use the two- or three-minute commercial breaks while you are watching TV to stand up. March in place, swing your arms or do some squats or leg lifts.

4. Catch up with friends while walking. Social visits often tend to be sedentary, so instead of meeting a friend for coffee or lunch, take a walk instead. Or take a stroll before or after a dinner date.

5. Take the long way. Whenever you drive somewhere, park in a spot farther from the door to get in some extra steps.