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19 Feb 2004

Damage control
Hi Fitness Doc. Probably a very elementary question I know, but can anybody explain to me the consequences that smoking would have on my VO2 max. From what I can gather VO2 max is more dependent on cardiac functioning as opposed to lung function. I've just quit after 4 years of smoking (+- 6 p/day), I'm 24 and am keen to find out how much damage I've done. I know "repairing" the damage is out of the question but are there any suggestions as to how I can assess the damage.
Answer 402 views

01 Jan 0001

Hi Nick

NOt an elementary question at all. VO2 max is dependent on both lung function and cardiac function, and so any variable that affects either of these will result in a decrease in lung function. I managed to find one study where VO2 max, and O2 levels in the blood are both reduced in smokers. Interestingly, these reductions seemed to be fairly reversible, and a week off smoking caused both to increase to pretty close to normal levels. THe reason for this is that smoking cause the carbon monoxide levels of the blood to rise, and carbon monoxide binds to hemoglobin, which means that there is less space available for oxygen to bind. The other thing is that as soon as your breathing becomes more uncomfortable, you stop exercise sooner, and so smoking exerts this indirect effect on VO2 max, because it will impair your breathing comfort, meaning that you can't exercise as hard, and therefore VO2 max will be lower.

The good news is that you will find these changes reverse quite rapidly, as I said earlier, and so if there is any need to feel good that you've quit smoking, that is it - pretty soon, you will be back near the levels a normal non-smoker would be.

SO, good luck with your progress, and keep training!
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