Cellular respiration is the process that occurs when glucose is turned into adenosine triphosphate, or ATP. This chemical provides energy for your body's working muscles. Depending on your exercise intensity, your body's cellular respiration process is carried out in one of two ways, aerobically or anaerobically.
Aerobic means "with oxygen." Aerobic exercise and activities are characterized by a slightly elevated heart rate that allows you to continue the activities for long periods. Aerobic respiration uses sustainable pathways for creating energy for your muscles. Oxygen allows your body to convert glucose into ATP more efficiently, without creating excess waste products. During aerobic activities, your heart rate increases to provide for the additional oxygen required, but not so high as to be unsustainable.
Anaerobic means "without oxygen." Anaerobic exercise usually consists of high-intensity activities including sprinting and weight lifting. During these activities your body cannot provide enough oxygen to account for normal aerobic respiration. Your heart rate elevates to near maximum levels, attempting to pump more oxygenated blood, but it cannot keep up. At this point, anaerobic respiration kicks in, converting glucose into ATP and creating a waste product known as lactic acid. Your body can absorb only so much lactic acid before your muscles cramp and seize. This is why anaerobic respiration is sustainable only for short periods.
Target Heart Rate
Your target heart rate is from 50 percent to 85 percent of your maximum heart rate. This range provides a foundation for determining your ideal exercise intensity for improving cardiovascular fitness, and also provides a generalized outline of your aerobic and anaerobic heart rate zones. Your aerobic heart rate zones are from 50 percent to 75 percent of your maximum heart rate. Your body begins using anaerobic respiration at around 75 percent of maximum heart rate and up. Maximum heart rate for men is 220 minus age. For women, max heart rate is 206 minus 88 percent of age.
Both aerobic and anaerobic respiration relate to different levels of exercise, each with its own benefits. Aerobic exercise burns more calories from fat, which makes it ideal for weight loss. Anaerobic exercise burns more calories from glucose, which helps build muscle strength. Both types of exercise improve your cardiovascular fitness. Combining the two can lead to lower levels of cholesterol and blood pressure, improving your heart health and reducing your risk of cardiovascular disease.