Is increasing lung capacity a misnomer?

Question

I have been under the impression that one cannot increase their total lung capacity, it's like the ratio of fast twitch to slow twitch fibers in your muscles, i.e. it is what you were born with. However, I was looking through research articles to confirm this, and I cannot find any articles that specifically address increasing total lung capacity.

I am aware that there are lung training devices out there that purport to increase capacity, but what they really do is train inspiratory muscle, and that neovascularization (increase in capillary and blood vessel counts to exercising muscle) also contributes to O2 delivery and increased O2 utilization.

Can anyone provide some studies directly addressing the increase in lung capacity and the effects on athletes thereof? I am aware of the studies in asthmatics, but they are not increasing the TOTAL lung capacity, they are increasing the FUNCTIONAL lung capacity. I am interested in ones where total lung capacity was shown to have increased.

Edited to clear up - What I'm looking for is any studies where the actual physical lung size has been shown to be increased. Lung volume is directly measured (spirometry, etc), but lung capacity by necessity is a finite value. I'm interested in finding out if there have been any exercises or other interventions that have proven to increase the lung size rather than the efficiency in which we use it?

Answer 1

This Scientific American article may help. It basically states that the improvements in cardio-respiratory function from exercise are due to the efficiency of the cardiac component rather than lung function:

Improvement in cardio-respiratory function does not result from changes in the lung's ability to expand, however. In general regular exercise does not substantially change measures of pulmonary function such as total lung capacity, the volume of air in the lungs after taking the largest breath possible (TLC), and forced vital capacity, the amount of air able to be blown out after taking the largest breath possible (FVC). Studies comparing TLC and FVC show little difference between regular exercisers and nonexercisers, in fact. ..........it is unlikely that pulmonary function limits their ability to exercise, unless they have a disease....

One of the largest differences between an exerciser and a nonexerciser concerns the heart's ability to pump blood and consequently deliver oxygen to working muscles. Cardiac output is a major limiting factor for prolonged exercise.

The article elaborates the efficiency improvements as:

...an exerciser typically has a larger blood volume, is better able to extract oxygen from the air in the lungs and is better able to extract oxygen from the blood at the working muscles than a sedentary individual is. Gas exchange involves not only oxygen delivery but also the removal of carbon dioxide, which is a byproduct of energy metabolism, and this process is also more efficient in an exerciser.

Hope that helps.