Oxygen uptake and lung capacity work together in order to deliver oxygen into the blood so that it can be transferred around the body. Oxygen uptake increases as a result of training causing an increase in the amount of oxygen being transferred in the blood for muscles to use in aerobic activity. However, lung capacity does not seem to change much, if at all, in response to training.
Oxygen uptake refers to the body’s ability to absorb oxygen through the lungs and into the blood, transport this oxygen sufficiently to the muscle and then transport the oxygen out of the blood and into the muscle cell where it is used for energy production. Oxygen uptake increases in response to training and allows for faster and more efficient delivery of oxygen to the muscles.
There are two main reasons for the increase in oxygen uptake: an increase in haemoglobin and myoglobin levels. Myoglobin is responsible for the transportation of oxygen out of the blood and in the muscle cell, taking it to where it is needed for ATP production in the aerobic energy system. Haemoglobin is responsible for absorbing oxygen from the lungs and transporting it through the blood. The more haemoglobin the more oxygen per mL of blood that can be transported.