Racing for science

Science experiments don’t get any tougher than this: the Blaze Niagara Escarpment Race, held in June, saw two teams of 10 ultrarunners cover 894 kilometres in a four-day relay, for a scientific study. The runners recorded their training and diet for two months prior to the race, and underwent testing for oxygen capacity, body composition and leg strength at the McMaster University High Performance Laboratory in Hamilton. At the start and finish of the race, blood and urine samples were collected from each participant.

Guided by McMaster’s well-known runner-researcher Mark Tarnopolsky, the project should yield new insights into the physiology of ultra-long-distance running. It will also answer some more offbeat questions, like how the carbon footprint of running compares to driving for long-distance travel. The Adventure Science group that organized the event has a number of future adventures planned, including a foot-powered search for dinosaur remains in the badlands of Alberta in 2010, and a search for lost Inca cities in Peru in 2011.

Run for your eyes

Add one more to the long list of body parts that benefit from running: your eyes. New analysis from the National Runners’ Health Study, a massive effort by Paul Williams of Lawrence Berkeley Laboratory in California that has tracked 55,000 runners since 1991, suggests that running lowers your risk of glaucoma, cataracts and macular degeneration. Moreover, the farther you run each week and the faster your 10K time, the lower your risk. For glaucoma, for example, risk decreased by five per cent for every kilometre in the length of the average daily run. Those who could run 10K in under 37 minutes were half as likely to get glaucoma as those whose best time was over 47:30. The results appear in three separate articles, one in Medicine & Science in Sports and Exercise (on glaucoma) and two in Investigative Ophthalmology & Visual Science (on cataracts and macular degeneration).

Williams suggests that lower glaucoma risk might result from a decrease in “intraocular pressure,” the fluid pressure behind the eye. There have been a few other studies suggesting that aerobic exercise may decrease intraocular pressure, but the mechanisms are still unclear – theories include changes in blood pressure, lactate levels, blood acidity and insulin resistance. Whatever the cause, the sheer magnitude of the study lends statistical weight to Williams’ central argument: running has a dose-response relationship, so the farther and faster you go, the greater the benefits.

We swear this works

If you’re looking for that extra edge that will allow you to hang on and maintain a punishing pace for the last kilometre of a race or the last interval of a hard workout, consider the latest research from psychologist Richard Stephens of Keele University in Britain. After hitting his thumb with a hammer, Stephens let loose with a string of expletives – and that left him wondering why we have that instinct. To find out, he had 67 volunteers dunk their hands in ice-cold water and keep them there as long as possible. Half of them were told to yell a word from their list of “five words you might use after hitting yourself on the thumb with a hammer,” while the other half chose their word from the list of “five words to describe a table.” The results appeared in the journal NeuroReport.

Sure enough, swearing significantly increased the length of time subjects could withstand the pain, by 30 per cent for men and 44 per cent for women – a difference that may have something to do with the fact that women swear less often, Stephens speculates. Swearing also raised heart rates and decreased perceived pain, again with a greater effect in women than men. What’s happening, the researchers think, is that we’re able to tap into our fight-or-flight mechanism – something that may come in handy next time you’re grinding to the top of a steep hill, as long as there aren’t any children within earshot.

Gulp, don’t sip

For most of us, taking in fluids while we’re exercising is a delicate proposition. We know we need to stay hydrated, but we don’t want a bunch of liquid sloshing around in our stomach while we’re trying to run. So the natural instinct is to sip delicately, hoping the small amounts will be absorbed more easily. But that’s not actually the case, according to Leslie Bonci, the director of sports nutrition at the University of Pittsburgh Medical Center. “When you take more fluid in, gulps as opposed to sips, you have a greater volume of fluid in the stomach,” she told the New York Times. “That stimulates the activity of the stretch receptors in the stomach, which then increase intra-gastric pressure and promote faster emptying.” In other words, taking in slightly larger amounts of fluid should leave your stomach feeling empty sooner than if you’d sipped.

How long does it take to get fit?

When you start exercising for the first time, you can expect large initial gains in fitness, followed by smaller gains as you continue. But how long does this process take? A study by German researchers published in Medicine & Science in Sports & Exercise explored this question by getting 18 sedentary volunteers to undertake one year of training, three times a week for 45 minutes. The subjects maintained a constant moderate effort level for their walk-jog program by monitoring their heart rate. That meant that, by the end of the year, they were running farther and faster than at the beginning, but the effort and time remained the same.

The researchers monitored fitness by measuring maximum oxygen uptake, running speed, and heart rate during exercise and at rest. The largest gains were seen in the first three months; by six months, most of the markers had begun to plateau. As a result, the researchers conclude, “beginners in recreational endurance exercise should be advised to increase the training stimulus after six months of training to maintain training effectiveness.” It’s important to note that even though the subjects were running faster by the end of the year, the stimulus was still the same because they weren’t trying any harder. So to keep progressing, try making one of your runs a little farther or a little faster each week.


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