Fat Vs. Aerobic Fitness

Fat plays an important role in your body, but too much fat can quickly lead to health problems ranging from heart disease to cancer. Roughly 16.3 percent of U.S. children and 32.9 percent of adults are currently obese, according to the American Heart Association. One of the most successful ways to help combat excess body fat is through aerobic exercise.

Purpose of Fat

Body fat provides several benefits -- for one thing, it helps cushion your internal organs. Fat is also used as insulation to help maintain a healthy internal body temperature. Body fat is a survival mechanism used to ensure you have a secondary source of energy when not consuming enough calories through your diet. As such, any time you consume more calories than your body needs for basic body function -- or to cover physical activity -- the excess calories can be stored as fat in adipose tissue located throughout your body. You can then access the fat later to create energy.

Effects of Too Much Fat

Excess fat as seen in those who are overweight or obese not only affects your physical appearance, but also impacts how well your body operates -- along with your overall risks for disease. For example, obesity can be linked to diabetes and the development of insulin resistance. Obesity is also connected to high blood pressure and the development of cholesterol plaque seen with heart diseases. Excess weight affects bones and joints, leading to problems with osteoporosis and arthritis. Obesity is even linked to higher cancer risks.

Aerobic Exercise and Energy

As you take part in any aerobic exercise, you increase the demand for energy in your body. When you perform enough aerobic exercise to burn more calories than the calories you take in through your diet, the body is forced to turn to other sources for calories, such as fat stored in your adipose tissue. However, for the body to access the energy in the fat, it must first break it down using enzymes called lipases into smaller parts like glycerol and fatty acids. Once fat has been broken down, it is exposed to oxygen to harvest or "burn" the calories in the broken down fat for energy. To do this your heart rate and respiratory rates are increased, supplying the additional oxygen needed, as well as increasing how quickly the broken down fat and energy can reach the cells that need more energy.

Aerobic Exercise and Fat Loss

The mitochondria of the cell uses the broken down fat and oxygen to create a chemical reaction that releases energy. By this point, all that's left of the broken down fat is waste products like heat, water and carbon dioxide. The carbon dioxide is placed back into the bloodstream where it exits the lungs. The heat is used to maintain body temperature, or is released from the body through the process of sweating. The water exits the body through breathing, sweat and urine. Once these final products leave your body, you see noticeable results regarding weight loss.

Recommendations

The Centers for Disease Control and Prevention suggests that all American adults strive for at least 150 minutes of moderately intense exercise each week. Moderately intense aerobic exercise includes activities such as walking, jogging, light swimming, hiking, riding your bike -- or using cardio machines at home or at the gym such as elliptical machines, stair steppers or treadmills. Moderate exercise should increase your heart and respiratory rate, but not so much that you have difficulty talking while exercising,