Doctors know it.
Insurance companies know it.
In fact, most Americans who engage in exercise know it - physical exercise is beneficial at any age. Life-threatening or debilitating diseases common in later life such as coronary heart disease, diabetes and osteoporosis can be positively influenced by frequency and type of exercise. Strength, important for performing daily tasks as one ages, also can improved by a regular strength training program. Continuous exercise, exercise that keeps the heart beating at a steady rate for 20-30 minutes such as walking or climbing stairs is considered an aerobic activity. Aerobic exercise improves blood and oxygen flow which in turn increases one's ability to participate in activities without becoming easily winded or fatigued.