Question

Explain how acute exercise would challenge the delivery of oxygen and release of carbon dioxide as well as how acute exercise may actually enhance the delivery and release of oxygen at the tissues via an explanation of shifting of the oxyhemoglobin dissociation curve, etc. Make sure to include information about hemoglobin and myoglobin structure and a full explanation of the sigmoidal shape of the dissociation curve (i.e. loading and unloading portions).

Answer 1

Exercise is a phenomena in which we stimulate our muscles to do extra work. Exercise could be in the form of running, cycling, gyming etc.

Now, since due to exercising, our muscles are activated more, these muscles need more supply of nutrients. As we know that oxygen is required by each and every cell of our body to oxidise food are gain energy from it, muscles also utilise more oxygen during exercise.

When we do exercise, our muscles work harder and consumes more oxygen than normal. Also more macronutrients are broken to form energy and thus more carbon dioxide is released.

Oxygen dissociation curve explains the association of oxygen to the hemoglobin and the factors which affects this association.

The normal dissociation curve is sigmoid in shape. It is because in the initial phase, high amount of oxygen gets attached to hemoglobin. As the hemoglobin gets saturated by oxygen, the binding decreases and curve gets flatter. In this way sigmoid curve is obtained.

Now, because of exercise, the dissociation of oxygen from hemoglobin increases and the curve shifts to right. Shifting of curve to right means that oxygen is unloaded from hemoglobin.

The curve shifts to left when oxygen is loaded with hemoglobin and hemoglobin gets saturated with oxygen. This occurs at lungs level.