Kinds of Exercises you can do after 30! According to the 2008 Physical Activity Guidelines for Americans , you need to do two types of physical activity each week to improve your health–aerobic and muscle-strengthening. 2 hours and 30 minutes (150 minutes) of moderate-intensity aerobic activity (i.e., brisk walking) every week and muscle-strengthening activities on 2 or more days a week that work all major muscle groups (legs, hips, back, abdomen, chest, shoulders, and arms). Moderate-intensity aerobic activity means you're working hard enough to raise your heart rate and break a sweat. Here are some examples of activities that require moderate effort: Walking fast Doing water aerobics Riding a bike on level ground or with few hills Playing doubles tennis Pushing a lawn mower Besides aerobic activity, you need to do things to str...