Health and Fitness

How running relates to your health and fitness or other health and fitness topics of interest to runners.

Running in polluted air

This article was originally posted by Ryan at the original Blogs.

Just one topic this week. The reason will be more clear if you read Thursday’s blog post.

This is a very interesting question, though. I think we’ve beaten the "running is good for you" topic to death recently.

But what about in pollution? This is a question I’ve wondered about frequently. I’ve always felt that running in pollution is probably better than not running at all and what limited research has been available has mostly confirmed that. However, there has been a lack of long term research on this topic.

Well, Alex Hutchinson found a study that covered this topic.

The result?

There were a few hints of possible interactions. For example, people who cycled or gardened were 45 percent less likely to die from respiratory diseases during the study than non-exercisers if they lived in low- or moderate-pollution areas, but only 23 percent (for cycling) or 19 percent (for gardening) less likely in high-pollution areas.

Common sense of course says breathing polluted air is bad for you and that’s clear in these results. That means, as much as possible, it is wise to avoid the most polluted areas. Try to stay away from busy highways when running and things like that. However, more importantly, exercise is better than none regardless of the air you’re breathing.

Running “too much” or “too fast” (probably) won’t kill you

This article was originally posted by Ryan at the original Blogs.


I was thinking of doing what would look more like a typical Monday post today with some content from last week. However, this week, some bad analysis of a study that’s been around for a while began appearing.

You may have seen the headlines: Fast running is as deadly as sitting on couch, scientists find or Too much jogging ‘as bad as no exercise at all’ or Stop that binge jogging! Three times a week is best for you… and too much is as bad as doing nothing

Whoa! Seriously? Sounds like I should reconsider my training routine. Or…maybe not.

Alex Hutchinson did a fine job covering this.

This quote sums things up pretty well:

Yes, the conclusion of the study (that "strenuous" jogging is as bad as being sedentary) is based on two deaths over more than a decade of follow-up. (Thank goodness a third person didn’t die, or public health authorities would be banning jogging.)

To summarize, there were simply not enough "fast" or "high frequency" runners to have a statistically significant result. The basic concept here is a fundamental rule of statistics. There is always variability in numbers. There are always random events happening. In order to truly pick up trends, you need a large sample size. If you only sample 10 smokers and 10 non-smokers, you might simply by chance find that both groups have the same number of people who have died from lung cancer. Sample 1000 of each, though, and you’ll start to see a trend where smokers more frequently die of lung cancer.

The same thing is going on here. You had sample sizes of 413 sedentary individuals, 640 who ran less than 1 hour a week but only 50 who ran more than 4 hours a week. If you look at the raw numbers, only 2% of those who ran more than 4 hours a week died in the next decade. A far lower percentage than the sedentary subgroup (though other factors such as age came into play also). However, because there were only 50 individuals, you didn’t have a statistically significant result.

Somehow the media spins "not statistically significant" into "running a lot is as dangerous as not running at all". That’s not at all what this study suggests. It just suggests there isn’t enough information to be sure the results mean anything.

So don’t fear the headlines. Understand what this data really says. We simply don’t know what the numbers would look like with a larger sample size.

Exercise as medicine

This article was originally posted by Ryan at the original Blogs.

I think most people accept that exercise is good for your health. Now, we have some evidence that it might also be a good medical intervention. Even as effective as commonly used medications, especially statin drugs which are very commonly used in lowering cholesterol of heart patients.

This is good news on a couple of fronts. First, on a personal front for those of us here, we’re doing good for our health. Just more proof of how good running or any activity is for us. Second, from a medical and public health perspective, this is an inexpensive treatment with fewer negative (and I’d argue more positive) side effects than the commonly prescribed alternatives.

More research on where exercise might be as beneficial as, if not more than, traditionally prescribed medical interventions should be explored. Maybe the results of this study will spur further interest in this idea.

On another note, I’m sorry I didn’t get anything posted last week. I do have a fairly short original post that should be ready to go tomorrow or Friday.

The couch potato marathoner

This article was originally posted by Ryan at the original Blogs.

I often find myself talking about the problems with going from couch to marathon in too short of a time. Well, what to make of runners who are both couch potatoes and marathoners at the same time?

To sum up the study, researchers at the University of Texas in Austin sent surveys to participants of the Austin Marathon and Half Marathon. 218 runners responded reporting peak training duration (total time training for their peak week) and average time spent sitting, as well as some other information such as anticipated finishing time.

The results found that, while the runners peaked at 6.5 hours (median) training in a week’s time, median sitting time was 10 hours and 45 minutes on workdays and 8 hours on non-workdays.

We already know from prior studies that time spent seated is extremely bad for our health, potentially regardless of the amount of exercise we get (though those studies generally looked at people who didn’t exercise nearly as much as these runners).

So what does this mean? Well, not a whole lot…yet. I’d like to see more. Small doses of exercise don’t seem to counteract the negative effects of spending large amounts of time seated. Do larger doses? That is a question I’d like to see answered. In the meantime, no matter how much we exercise, maybe we should try to spend less time seated.

Sorry for the lack of long form posts this week and last. Some family matters kept me from being able to finalize anything I have in the works. I expect to be able to post one next week.

Why Runners Don’t Get Knee Arthritis

This article was originally posted by Ryan at the original Blogs.

I’ve never really bought the idea that running is bad for your knees. I know anecdotal evidence isn’t always sound but my experience has always been that long time runners who didn’t have pre-existing conditions were as healthy as, if not more than, less active people. Now, not only do we have evidence that the widely held claim that running causes knee arthritis is false. We have an explanation for why this might be.

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