Question

1. When we (humans) exercise we need energy. Why do we need this energy? Where do we get this energy from? Certain tissues which account for 40-50% of our body mass utilize a lot of energy and are especially important in exercise. Describe in detail how the “energy” gets to this tissue and how it is utilized by this tissue during low and vigorous exercise. What happens when the tissue does not have enough “energy” and when would a situation like this occur?  Can we improve the amount of “energy” that this tissue gets? If we can how would you do this when a person is at rest?

Answer 1

One of the main reasons why the body requires energy is to perform the metabolic as well as the regulatory function of the body. The main source of energy or the energy currency is the ATP required in the body is ATP which is produced within the mitochondria of the cells. As one exercise, here are the things that happen

· Increase in the heart rate which is caused due to the increased blood circulation. This happens because of the requirement of the muscles for more oxygen and hence the heart rate increases for supplying more oxygen to the body.

· There is increase in oxygen requirement in the lungs. With exercise there is heat product that tend to dilate the blood vessels and helps in enhancing the rate of blood circulation.

There are majorly two sources of energy which is used by the body during exercise. The primary source of energy is provided by breakdown of carbohydrate or glycogen and through the glycolytic cycle it produces glucose. The glucose enters the blood circulation and taken in the cells where the mitochondria produces ATP used as energy. The second source is fat breakdown which is aerobic process and this also helps in ATP production.

When one is performing low intensity exercise like weightlifting for example, the main source of energy comes from breakdown of fat. The fat is broken down into fatty acid and glycerol. This enters the bloodstream and hence enters or reaches the tissues where the cells absorb it to convert it into ATP inside the mitochondria. On performing intense and high-intensity workout, the primary energy source comes from breakdown of carbohydrate which produces glucose and it is absorbed in bloodstream. It is carried to the tissues via the bloodstream and enters the cell where the mitochondria produces the ATP, hence energy.

Now, when the body does not have enough source of carbohydrate and fat, it is not able to produce enough energy. This means that due to the lack of energy, the muscles tend to breakdown their own muscle tissue which produces amino acid and used for running the functions. This leads to malnourishing of the body, extreme fatigue and improper functioning of the body function, regulation and metabolism.

The best way to increase energy reaching the tissue when the person is at rest is by consuming a balanced diet which has balanced proportion of carbohydrate, proteins and fats. It is important for a person to get plenty of rest as it helps in restoring the regulation of the body.