While maintaining a healthy weight is very important, participating in physical activity is just as important. Physical activity on its own may even help lower your risk of colon cancer and breast cancer. On top of it helping to reduce your risk of cancer, it is also good for your body and joints to be active. You do not have to have access to the outside to do some physical activities, either. Walking in place or doing squats during a commercial break is better than sitting around on the couch and not moving around at all. 

Adults who participate in any amount of physical activity gain some health benefits, as well. However, it will take more than just walking around the block one time to have any effect. For substantial health benefits, try to get around 150 minutes of moderate physical activity in a week or about 75 minutes of vigorous aerobic exercise in a week. You can also do a combination of both. Try to make a goal for yourself that includes 30 minutes of physical activity in your daily routine. Of course, if you just so happen to do more, then that is even better.