The internet is a wonderful tool as far as getting workout ideas. I came up with a 10-minute challenge today: 10 minutes of nothing but simple push ups. Do as many as you can and minimize the rest periods. This workout is short. And it complies with my philosophy of working out: A workout must be fast and effective. In the video below, you can see how to do them properly.
See how many you can do. I managed to do 100 in 10 minutes. Grab a timer, and just do them. Push yourself. Begin slowly, and build up your strength. Keep tabs and track your progress.
