Danish study: moderate jogging, higher benefits | Hacker News Reader

Danish study: moderate jogging, higher benefits

latimes.com

29 pointsmkempe20 comments

The error bars for strenuous exercise in the publication are laughable. Out of a population of ~1000, only 36 were strenuous joggers and only 2 of them died.

This is not the first time I've come across badly executed studies on running and long-term health. It's unsettling, and misleading.

7mph is a speed a lot of people can't run. Those are 8 1/2 minute miles. It corresponds to a speed of 26min for a 5k.

This article

  http://www.letsrun.com/forum/flat_read.php?thread=4612823

has some stats for a 5k race. The average time for men was 28min, and only 10% of the women were faster than 26min.

Slower speeds might skew towards women, who naturally live longer.

Another thought is that people who run fast do so over shorter distances, and their volume isn't sufficient to see a health bump.

12 km/h isn't particularly unachievable. I'm middle-aged, heavily built, run to and from work a couple of times a week and otherwise do no cardio exercise. I've built up to that kind of pace over a couple of years.

It's easier if you run at that pace for 20 minutes, 3 times a week...

If someone wants to work out these stats properly, Parkrun[1] has an excellent dataset ready for scraping.

Eyeballing [2] 26:00 will get you 93rd out of 300, ie top 1/3rd. That's probably achievable by someone who runs regularly (3 times a week). On [3] it gets you 362/844.

[1] http://www.parkrun.com/

[2] http://www.parkrun.org.uk/aberdeen/results/latestresults/

[3] http://www.parkrun.org.uk/bushy/results/latestresults/

Anecdotal opinion of someone that ran 6:50ish per mile pace yesterday in the SF Kaiser Half-Marathon and thus am apparently shortening my life... Those of us trying to run faster and be competitive (whether with ourselves or others) really don't care if we lose a few years of life. Quality over quantity! These articles come up every so often and seem to just serve as reasons for sedentary people to feel smug about their life choices.

I highly disagree with the last part. There are 2 reason to run as you mention: for health and for competition. Those running for health should be careful about emulating the routines of those running for competition.

A fair point. You're probably not running on average sub 8:30 miles unless you are training for performance in some form or fashion. Because it generally hurts quite a bit. :-)

With the "speed cutoff" You are also probably getting a higher percentage of males who of course have shorter life expectancy rates than women.

Since the study did not report nor account for other physical activities, it should be noted that a vast number of people in Copenhagen ride bikes around town. [1] 36% commute by bicycle; municipal ambition is 50% by 2015.

[1] http://en.wikipedia.org/wiki/Transport_in_Copenhagen#Cycling

Yeah, "couch potatoes" in Copenhagen likely rank in the 90th percentile in terms of overall physical activity for most American cities.

What this study says is, "Running really fast (> 7mph for four hours a week is not exactly a cakewalk) for long periods of time might reduce your mortality.

> might reduce your mortality

might increase your mortality, actually. That is reduce your life expectancy.

Argh, you're right, reduce your life expectancy.

Strenuous jogging is called running. </pedantic runner>

Here are the charts with the confidence intervals: http://content.onlinejacc.org/article.aspx?articleID=2108914

It is crazy they would present a subgroup analysis with 40 people, the effect would have to be enormous to find anything.

And yet the difference between the strenuous and light joggers are significant (the light jogger mean is outside the strenuous jogger 95% confidence interval and vice versa).

Actually, life expectancy of world class aerobic athletes (unlike power (anaerobic) ones) is a little higher than average according to studies in US, Spain, Germany, Poland... Could be a little lower than life expectancy of those involved in moderate aerobic activities though, I guess.

TL;DR; strenuous jogging doesn't have health benefits. There isn't enough data from the study to support any stronger conclusions.

The study indicates that strenuous jogging has the same benefits as no jogging, while moderate jogging improves life expectancy.

The study seems badly performed and with a small test group—I would not be so quick to draw such a large generalization from it.

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