THE NEW RULES TO WORKING OUT.

Weight Training:

• Adults should train each major muscle group two or three days each week, using a variety of exercises and equipment. 

For each exercise, 8-12 repetitions improve strength and power; 10-15 repetitions improve strength in middle age and older persons starting exercise; and 15-20 repetitions improve muscular endurance.

Cardio Training:

• Adults should get at least 2.5 hours of moderate intensity exercise per week.

To meet these requirements, perform 30-60 minutes of moderate-intensity exercise five days per week or 20-60 minutes of vigorous-intensity exercise three days per week.