Running does not have to be your only option for cardio exercise. Cardio training is any activity that increases your heart rate; which can include anything from climbing stairs to a step aerobics class at the gym to a vigorous Ashtanga yoga class. Finding an activity you enjoy doing will help you get the 30 minutes of moderately intense cardio you need five days each week, as recommended by the Centers for Disease Control.

Swimming

Swimming is a low-impact cardio exercise that is easy on your joints but can be a high calorie burning workout. According to Harvard Health, a 155 pound person can burn 446 calories swimming leisurely for an hour. Swimming offers a total body workout because your arm muscles are engaged to pull your body, your lower body work to propel your body with a kick and your core works to stabilize your body in water.

Hiking

Hiking increases your lean mass causing you to increase your metabolism and boost your calorie burn. Hiking involves unpredictable terrain, which keeps your body challenged and your muscles active. A seven year study on green exercise conducted by Dr. Jo Barton and his colleagues of the University of Essex, indicates that outdoor exercise, like hiking, can boost your mood and self-esteem because of the effects of nature. Hiking can also be a social activity that you can do with a friend or as a member in a local hiking club.

Indoor Cycling

Indoor cycling is a high-calorie-burning workout performed on a stationary bike; it can help sculpt lean legs. The high calorie burn from the exercise comes from interval training, along with adding resistance to your bike. For example, in class you may interval train by sprinting for 30 seconds, followed by one minute at a moderate pace. You may increase your resistance to mimic riding up a hill, which can help increase lean muscle mass.

Kickboxing

You can take kickboxing classes at your local gym or purchase a DVD. Kickboxing is a high-energy activity and a challenging way to train aerobically. Using a combination of kicks, punches and cardio moves, you can increase your lean mass, blast calories and melt fat from your entire body. Kickboxing classes are set up in a group fitness setting, which may help you stay motivated to complete the entire class.