Cellular respiration includes the reactions in the cells of your body when they convert the food you eat into a molecule of energy called adenosine triphosphate, or ATP, a form your cells can use. Light household activities or sitting down to watch TV requires a steady supply of ATP. When you transition from daily activities to exercise or when you have to carry laundry up several flights of stairs, your body needs a rapid burst of ATP.
Aerobic or Anaerobic
Your cellular respiration or cellular metabolism can be aerobic or anaerobic. These are processes in which energy is converted from the food you eat into energy molecules that the cells of your body can use. Aerobic respiration occurs in the presence of oxygen, while anaerobic metabolism occurs in the absence of oxygen. The type of respiration you use depends on the intensity and duration of your exercise.
The 90-Second Barrier
Anaerobic respiration takes place at the onset of exercise for up to 90 seconds. Repeated bouts of short and intense exercise, such as sprinting, increases the rate of anaerobic respiration. If exercise continues beyond 90 seconds, the cells rely on aerobic respiration to make energy, increasing the rate of aerobic respiration. Weight training and sprinting rely on anaerobic respiration, while running a half-mile or longer race or taking an aerobic dance class engages aerobic respiration.
What Happens Where
Anaerobic respiration occurs in the watery fluid inside the cell. Aerobic respiration takes place in an organelle or structure inside the cell called the mitochondria.
The anaerobic process relies solely on carbohydrates to make energy. The aerobic process uses carbohydrates and fats to produce energy. If most of your training consists of highly intense exercises, you must consume enough carbohydrates to fuel anaerobic respiration. If most of your training lasts more than 20 minutes, you can reduce your carbohydrate intake for your body to break down stored body fat to fuel aerobic respiration. Performing more anaerobic exercises compared to aerobic exercises will enhance the rate of anaerobic respiration; doing more aerobic exercises will increase the rate and efficiency of aerobic respiration.
Comparing the Two
Long duration aerobic exercise burns fat to produce energy. Still, short and highly intense exercise burns more total calories and increases the amount of enzymes responsible for breaking down fat, according to a 2009 article by Brad Schoenfeld and Jay Dawes, published by the National Strength and Conditioning Association. Incorporate a combination of intense anaerobic exercise and low- to moderate-intensity aerobic exercise within your training week to take advantage of the benefits of both types of cellular respiration.