dr. mark seigel. >> hi, ainsley, how are you? >> immigrate. fact or fiction, your body needs days off from exercise. >> that's a fact you need days off. here's why you need days off. your muscles get exhausted they get worn down. you can have more injuries if you exercise 7 days a week. i also think exercise is addictive if i tell people they are going to plan their days off two-days becomes three-days becomes 4 days. shoot shoot for 7 days you will never do it. >> you won't do 7, you will do 6. >> fact or fiction, the best way to work out is going hard every time. >> you actually injure your muscles. you build up free radicals and muscles wear down. exercise tends to wear down your muscles and it's the recovery that builds up your strength. >> take an tins cardio class or a pilate's class? >> you want to go in your zone increasing little by little. you don't gooif a car or your body 100,000 dollars. >> ymuscles get stronger? >> exercise stresses muscles. when you are recovering from exercise that's when they repair and get stronger for the ne