I have done many races where — be it mountain bike or running race — there will inevitably be that one athlete (usually quite a fit one too) who will light up after. While personally I could not think of anything worse, we all have our vices that get us through, be it a morning coffee or a post-race beer.

From top footballers to marathon runners, there are those die-hards that just won't quit. Even some Olympic competitors take the odd puff to ease the pressure. While smoking was banned in the Olympic Village, apparently there were designated smoking areas, and one athlete confessed that he saw many athletes smoke there.

Some athletes claim they need to smoke as it helps to keep their weight down, while others believe it opens up the lungs and helps them to relax.

Smoking versus exercise

Surely from a fitness and health perspective, smoking is one vice that shouldn't be mixed with exercise?

Certainly, for those who can't give up, exercise offers some protective effects against the well-documented risks of cigarette smoking.

A 2006 study published in the journal — Cancer Epidemiology Biomarkers and Prevention — showed that women who were current or former smokers and who also did high levels of physical activity were less likely to suffer from lung cancer than inactive ex-smokers.

Both exercise and smoking affect the same organ systems, but in opposite ways. The great contradiction is that while smoking decreases lung capacity, exercise increases it. In addition, as smoking increases your risk of having a heart attack, exercise decreases it.

But then there's the issue of phlegm — smoking produces phlegm (which congests the lungs), while exercise breaks it up and rebuilds the lungs.

Smoking also decreases the body's ability to absorb oxygen. Even a modest amount of carbon monoxide in the lungs decreases your body’s ability to absorb oxygen. It also decreases the amount of oxygen your body transports to your muscles, meaning less muscle growth.

A smoker's heart rate is also elevated and so when they exercise, the effort seems more arduous and the heart rate speeds quickly. Therefore a smoker's heart will have to work harder to do the same amount of work a non-smoker does.

Smoking also increases one's fatigue level during and after an exercise session. Endurance is reduced and physical performance may not improve as much as if they did not smoke.

So although someone could be fit and smoke, they would still be damaging their bodies (albeit less than inactive smokers) and increasing their chances of disease, while at the same time making it harder for their bodies to perform at their best.