What happens to the lungs during exercise?

• The rate and depth of breathing increases.
• A higher percentage of oxygen is extracted from the air available.
• More blood flows through the lung capillaries to expel CO2 and absorb O2.
  

What are the long-term effects of training on the pulmonary system?

Aerobic training such as swimming, jogging and cycling:

1. Increased capillary density around alveoli.
2. Increased endurance of respiratory muscles.
3. Increased respiratory muscle power.

Anaerobic training such as weights and sprinting:

1. A small increase in power of respiratory muscles.
   

What do these training effects mean to the athlete?

Aerobic training will bring about an improved blood flow (and therefore oxygen absorption) in the lungs. More blood flowing past the alveoli means more haemoglobin is potentially saturated with oxygen. Also, more CO2 can be expired. This increase in the supply of oxygen to the working muscles and an improvement in the endurance of the respiratory muscles means that the athlete can work much harder for longer periods. These pulmonary changes coupled with the muscular improvements in aerobic respiration mean the athlete will see a vast improvement in performance.