Can biomechanical analysis cure Dathan Ritzenhein’s injuries?

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As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

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Dathan Ritzenhein just announced that he’ll be running the New York City Marathon this November, joining a stacked field that already includes Haile Gebrselassie and Canadian hope Simon Bairu. One thing that jumped out at me from the press conference (as reported by Letsrun) was his coach Alberto Salazar’s assertion that Ritz’s injury problems are a thing of the past thanks to some high-tech analysis:

“Gordon Valiant – the head of biomechanics for Nike – did an evaluation of Dathan and was able to find some things that are unique to Dathan with the way he runs and strikes his foot. With that (study completed), we now have some modified inserts. I wouldn’t call them orthotics – just an insert into the shoe where he has an abnormal amount of force near his third metatarsal. It seems to have alleviated his symptoms completely and we’ve retested him in the lab and shown those forces have been lessened tremendously.”

For those who’ve been following the barefoot running debate, this should raise some flags. For years, critics of the big shoe companies have pointed out that measuring forces in a lab setting doesn’t necessarily equate to a change in injury rates. Australian minimalist advocate Craig Richards said as much in an article I wrote back in 2008:

“Shoe researchers and manufacturers will try and bamboozle you with the results of hundreds of biomechanical studies,” [Richards said]. While these studies tell you how your stride is affected by the shoe, “they cannot currently tell you what this means for either the injury risk or performance of the wearer.”

Fair point — though, as I pointed out last month, minimalists are suddenly more enthusiastic about biomechanical studies now that Dan Lieberman and others have provided them with some studies of their own.

Anyway, we now have a study (with n=1) in which the manipulation of biomechanical forces in the foot is hypothesized to solve a longstanding injury problem. The outcome measure: whether Ritz makes it to New York in one piece, with an uninterrupted build-up. Here’s hoping!

How calorie restriction extends lifespan

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As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

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British researchers are presenting some new research on how calorie restriction works at a conference on aging research this week. In a mouse experiment, they found that it reduces cell senescence (the point at which a cell can no longer replicate) and helps protect telomeres (which exercise does too, researchers have recently found). Interestingly, the effects seems to be significant even if if it’s only started later in life and maintained for a relatively short period of time.

As I blogged about recently, I’m a little ambivalent about this whole calorie restriction thing. I just can’t see a happy ending — if it works, you feel guilty about eating for the rest of your life, and if it doesn’t, you die! Ultimately, I respect that we want to know how the body works, and this line of research is part of that. But I was happy to see some of this ambivalence reflected in the quotes from the press release describing the research:

Professor Thomas von Zglinicki, who oversaw the research, said: “It’s particularly exciting that our experiments found this effect on age-related senescent cells and loss of telomeres, even when food restriction was applied to animals in later life. We don’t yet know if food restriction delays ageing in humans, and maybe we wouldn’t want it. But at least we now know that interventions can work if started later.

And a recognition that extra years aren’t the only thing that counts:

Prof Douglas Kell, BBSRC Chief Executive and keynote speaker at the BSRA Conference, said: “As lifespan continues to extend in the developed world we face the challenge of increasing our ‘healthspan‘, that is the years of our lives when we can expect to be healthy and free from serious or chronic illness.

Do the health benefits of cycling outweigh the risks?

THANK YOU FOR VISITING SWEATSCIENCE.COM!

As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

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In a Jockology column last summer, I described a few studies about how switching from car to bike for a commute affects your exposure to pollution:

Whether you’re better off inside or outside a vehicle seems to depend on the vehicle and location. A Danish study in 2001 measured pollution exposure while driving or biking along identical routes in Copenhagen. The air inside the cars was bad enough that, even taking into account that cyclists were taking longer and breathing more deeply, the drivers were worse off. On the other hand, an Irish study in 2007 found that the air on buses was worse than the air breathed by cyclists, but that the higher breathing rates led to greater total exposure for cyclists.

It’s one of those issues that might make you think twice about cycling through a busy downtown core to get to work — that, and the risk that you’ll be flattened by an impatient driver. There’s an interesting study that just appeared online in the journal Environmental Health Perspectives weighing the balance between cycling and driving in cities (the full text is freely available here). They make an interesting distinction between what’s good for society and what’s good for you:

Though society may benefit from a shift from private car use to bicycle use (e.g. because of reduced air pollution emission), for the shifting individual disadvantages may occur. While the individual may benefit from increased physical activity, at the same time he/she inhales more pollutants due to an increased breathing rate. The risks of getting involved in traffic accidents may increase as well as the severity of an accident.

To tackle this question, the researchers (from the University of Utrecht) crunch an enormous data set to determine what would happen if 500,000 people switch from car to bike for short trips in the Netherlands (though they argue that the conclusions are widely applicable in other countries). They use demographic information along with studies on air pollution, traffic safety and physical fitness to reach the following encouraging conclusions:

For the individuals who shift from car to bicycle, we estimated that beneficial effects of increased physical activity are substantially larger (3 – 14 months gained) than the potential mortality effect of increased inhaled air pollution doses (0.8 – 40 days lost) and the increase in traffic accidents (5 – 9 days lost). Societal benefits are even larger due to a modest reduction in air pollution and greenhouse gas emissions and traffic accidents.

One of the interesting points that emerges in their discussion of the pollution studies is how big a difference your route choice can make (which I also discussed in the Jockology article linked above). In fact, they cite one study that found “walking close to the kerb in London greatly increased personal exposure”!

(via USA Today and — once again! — Amby Burfoot)

Bike-run time is fastest when you go all-out on the bike

THANK YOU FOR VISITING SWEATSCIENCE.COM!

As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

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For the triathletes out there, an interesting study has been posted online for publication in a future issue of the European Journal of Applied Physiology: “Combine cycle and run performance is maximized when the cycle is completed at the highest sustainable intensity.”

A pair of Australian researchers asked a group of triathletes to perform a series of four 20K bike/5K run time trials, with the intensity of the bike ride varying from 80% to 100% of max intensity (compared to an isolated bike trial they’d done previously). As expected, going harder on the bike led to slower times for the run — but the effect was most pronounced for just the first kilometre of the run, after which it didn’t really matter how hard the subjects had gone on the bike. As a result, the fastest overall bike-run times came when the effort on the bike was highest. In other words, holding back in any way on the bike loses you time that you can’t make up on the run.

Now, there are a number of caveats. The study was small (5 men, 3 women), but the effect was very clear-cut (average times of 62:40, 59:53, 58:29 and 56:37 for the four trials, going from easiest to hardest for the bike leg), so that’s not likely to be an issue. The fact that the distances were 20K-5K instead of 40K-10K is unfortunate. The authors do a song and dance about how the sprint distance is “growing in popularity” so that’s why they decided to study it, which seems absurd. I assume the real reason is that it would have been much harder to get volunteers to do that many 40K-10K efforts in succession. Also, it was a lab study done on stationary bikes with no wind resistance, and the triathletes were recreational — their average 5K time (not preceded by a bike ride) was 19:51.

Still, bearing all these things in mind, it’s a data point:

It is unclear if this relationship would hold for longer-style triathlon race formats, full triathlon races which also include a prior swim leg, races that involve a draft-legal cycle leg or with highly trained or elite triathletes. However, our results suggest that time lost on the cycle leg is unlikely to be made up on the run leg.

Sailing on Lake Superior

THANK YOU FOR VISITING SWEATSCIENCE.COM!

As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

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Not really related to sports science, but a story I wrote for Canadian Geographic about a sailing trip on Lake Superior that I took last year (from Thunder Bay to Red Rock) is now available online. It’s an absolutely beautiful area, and I hope to visit again before long.