Possibly a stupid question, but: Is there any more Oxygen in the air when it rains? I ran in moderate rain today for 29 minutes, with an average heartrate of 161bpm. On Wednesday I ran in the dry at the same time of day(with similar daily calorific and water intake) for the same distance taking 31 minutes with 167bpm. The run in the rain obviously 'felt' easier. A friend(really) claims that this is because there is more oxygen in the air during and just after rain. He can offer no explanation or source but is confident and I think he is genuine. I have experienced easier running in the rain before but only have anecdotes for it, and have asked google, but to no avail. Could the cooling act of the rain result in increased local atmospheric density? Could the trees being pumping more oxygen in the rain? Is it psychosomatic? Is it just complete nonsense? thanks, Twist
That would make sense. Cooler air means you suck down more molecules with a breath than with thinner air. It's like how some professional runners train in high altitude so when they race in lower altitudes, their body is conditioned to suck up more oxygen during the run. If you run in primarily hot air and then its cool one day, the run will be easier. Then there's also the effect of having your body not overheat as fast in a cooler environment. Trees might produce more oxygen when it rains, after a dry spell, because photosynthesis needs all that good water. But on the other hand, when it rains it usually is not sunny, so having more water but less sun might normalize the chemical process where the difference in oxygen production is unnoticable.
Rain removes impurities and polutants from the air including carbon dioxide, which is more water soluble than oxygen, so oxygen remains in the air more than carbon dioxide. This would increase the concentration of oxygen in the air. Also, as you said, the air will be denser since it is cooler so again the oxygen concentration will be higher - but I don't know how much of a difference both effects will make. The rain helps to keep you cool when running which may help. Additionally you may enjoy the rain (you said it felt easier). (I wouldn't assume the trees are having an effect - it will be cloudy so photosynthetic rate will be lower. The trees reaction to newly available water is not instant - probably taking several hours)
Cooler denser air is a minimun effect (Ideal gas law) As muscle work created a lot of heat, it's more likely that the additional liquid cooling device kept the body temperature on more desirable levels.
Wow. Brilliant answers, thanks very much Please Register or Log in to view the hidden image! Body temperature makes a difference because sweating takes effort and thus more oxygen? Rain cools, so less sweating, less oxygen demand?
Body temp makes a difference because sweating causes dehydration. If you are not sweating as much you will not feel as thirsty, tired or distracted and so running faster is more comfortable than if you are sweating more. Oxygen demand stays the same (if you are running at the same speed - more or less). Also feeling hot in itself, before sweating, makes you uncomfortable and makes you want to put in less effort to try and stay cooler (subconscious mostly). Overall the cooling effect will mostly be a psychological benefit since the dehydration and heat will not be enough to affect the body yet.
Wow, so this is the more reason to love rain? If you geniuses didn't post anything, I'd post saying that running better under the rain is because of the cooler temp.... I admit that when it's hot (air and body), I hate to do much things....
Doesn't the rain cause friction in the air? Which oxidies the O2 and makes Ozone? So wouldn't this reduce the amount of available oxygen in the air? But I agree, sweating is really going to help. I go running on a regualr basis, the best time to run is when it is hot, as I do middle distance mostly. I think it helps train your body to use the muscle more efficiently as long and you take fluids with you.
I know that lightning creates quite a bit of Ozone. I can certainly smell the ozone of approaching storms.
