Exercise is not an option if you want good health, because good health is not guaranteed. It takes work to be healthy, and I believe interval training is a great exercise plan. If done correctly, hormones are released to keep the endocrine system running properly and that is a great base for good health.
Exercise is not just for muscle tone, it will help you sleep better, digest better, is great for mental health and focus, helps keep your immune system strong and much more.
I believe interval training is one of the best cardiovascular exercise plans as our body is built for fight or flight.
Choose your favorite exercise….swimming, running, dancing, biking and create an interval training program to that exercise. Warm up for three minutes, then go as fast as you can for thirty seconds, then back to a recovery period of low intensity for ninety seconds. Do that for eight rounds and you have only spent about 25 to 30 minutes. Three days a week should be sufficient for good health along with another two days of some strength training to keep your bones strong.