Can you “acclimatize” to cold temperatures?
I’ve been blogging a bunch about heat (it is summer, after all), so I figured for balance I should mention this new study in the European Journal of Applied Physiology about acclimatization to cold, since it’s not a topic we hear about much. Researchers at Kent State compared five “cold-weather athletes” with eight controls matched for fitness, physical activity, size, etc., in a graded cycling test to exhaustion at 5 C. The result: the cold-weather athletes were more efficient than the controls:
Specifically, [cold-weather athletes] had ~20–30% lower VO2 at submaximal workloads, compared to [non-cold-weather athletes].
Cool, huh. So what’s going on here? Well, they don’t really know. When we talk about heat, we know there are specific physiological changes that occur with acclimatization, like increased sweat rate and blood flow to the skin. The researchers suggest that it’s “possible” that cold-weather athletes were “more able to buffer lactate at a given workload due to their experience with exercising in cold ambients,” though it’s not clear to me why that would be.
Another point worth mentioning is that the cold-weather athletes were actually football players, and their cold-weather exposure consisted of about 10 hours a week of winter practices in temperatures hovering around freezing. Morever, they were special teams players (punters, kickers, long snappers), “so it follows that they did not acquire as much activity as other athletes on the football team (i.e., only 20–30 min per practice were spent doing kicking drills and the rest of the time involved mainly standing or sitting in the cold).”
Oh. So these were not speed skaters or something. So I’m not convinced that there was any serious cold acclimatization. And as far as I can tell, the study didn’t have a control trial to make sure that the football players weren’t just more efficient (from better training) than the controls under all conditions. (They did a familiarization trial at room temperature, but didn’t analyze the results). All in all, I think the only thing we can conclude from this study is that “cold acclimatization” is an interesting concept that doesn’t get enough attention and merits further study.