Before starting any exercise program please consult your doctor. Especially if your over 45 years of age, male or 50-55 years for female. Or if you have not been active for a while or have any pre-existing medical condition, especially if you have any kind of heart problems or history of heart problems. Also, see your MD first if you have a BMI over 25. Always a good idea to check with your MD before beginning any fitness program.