Aerobic exercise reduces the risk of many conditions, including obesity, heart disease, high blood pressure, type 2 diabetes, stroke and certain types of cancer.Aerobic exercise helps lower high blood pressure, control blood sugar and relieve chronic muscle pain. If you've had a heart attack, aerobic exercise can help prevent subsequent attacks. Aerobic exercise activates your immune system. Aerobic exercise increases the concentration of high-density lipoprotein (HDL, or "good") cholesterol and decreases the concentration of low-density lipoprotein (LDL, or "bad") cholesterol in your blood. Aerobic exercise can ease the gloominess of depression and reduce the tension associated with anxiety, as well as promote relaxation. Increase your stamina. Aerobic exercise may make you tired in the short term. But over the long term, you'll enjoy increased stamina and reduced fatigue. Aerobic exercise keeps your muscles strong, which can help you maintain mobility as you get older. Aerobic exercise also keeps your mind sharp.