Exercising is definitely an essential component to living a long and healthy life, but the key is to do it on a very regular basis. A study found that people in their 70s who have been exercising regularly for decades seem to have put a brake on the aging process, maintaining the heart, lung and muscle fitness of healthy people at least 30 years younger. Find out more about the stories of some of the old-timers who managed to keep the same cardiovascular health they had almost four decades ago.