Exercise: more is better, and the harder the better

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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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Great article in the Wall Street Journal about Paul Williams’ National Runners’ Health Study. As I wrote last summer:

What Williams really emphasizes in his recent studies is the “dose-response” relationship between running and health: the farther and faster you run, the greater the benefits.

But this isn’t a very popular message among public-health advocates, who are struggling to convince people to do any exercise at all, let alone worry about how hard they go, according to WSJ’s Kevin Helliker:

In Dr. Williams’ study of more than 100,000 runners over nearly 20 years, stepped up exercise was found to have some powerful benefits. But his research is controversial. While Dr. Williams is well respected by other exercise scientists, he is shunned by those in the public-health field. Dr. Williams is routinely excluded from committees charged with formulating exercise guidelines, and his grant proposals are often rejected as irrelevant because few exercisers want to hear the word “more.” Public-health officials also worry that touting Dr. Williams’s research could discourage the sedentary from doing any exercise at all, or lure them off the couch with goals too lofty to engender success.

It’s an interesting dilemma, but ultimately I believe in simply telling the truth, even if it makes the message more “complicated.” More exercise is better, and if you’re simply meeting the standard exercise guidelines, you’re leaving a lot of potential benefits on the table:

A number of [Williams’] studies have taken direct aim at current exercise guidelines, by comparing the benefits of mere compliance with the benefits of running far beyond them. A Runners’ Health study published in the journal Stroke last spring found that men and women who ran more than eight kilometers a day had a 60% lower risk of stroke than those who ran at the guideline levels. An article published in September in the journal Atherosclerosis found that those Runners’ Health participants who exceeded guideline levels had a 26% lower risk of coronary heart disease than those who ran at guideline levels.

Jockology: Group exercise gives you extra endorphins

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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This week’s Jockology column takes a closer look at the idea that group exercise offers some benefits that solo sessions don’t.

The question

Will taking a class or finding training partners help me keep my exercise resolutions this year?

The answer

Consider the similarities between a modern exercise class and an ancient religious rite – the wise leader guiding the group through a series of ritualized movements, in perfect synchronization. If you’re struggling to keep faith with your fitness goals, this apparent coincidence might offer a solution.

New research suggests that group exercise unleashes a flood of chemicals in the brain, triggering the same responses that have made collective activities from dancing and laughter to religion itself such enduring aspects of human culture. For some (but not all) people, finding workout buddies could help turn fitness into a pleasant addiction. [read on…]

Obviously people have a lot of different reasons for working out in groups — or for working out on their own, for that matter. But I found the study of Oxford rowers described in the article to be one of the most interesting studies of 2009. In the running community, there’s a lot of debate about why so many athletes stop competing seriously after they finish university. Again, there are clearly many different reasons — but I’ve heard a lot of runners say that the training experience just isn’t the same once they’re no longer part of a group working out together and sharing common goals. Maybe this is really just a form of endorphin withdrawal!

Artificial sweeteners can’t fool your subconscious brain

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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Here’s a mystery: Why is obesity still such a problem in the age of the magic zero-calorie sweetener? New Scientist has a great article on the latest brain-scanning research, which offers some hints about how these sweeteners may fool us on a conscious level, but don’t manage to trick our unconscious minds. These new studies suggest that “zero-calorie” options may really just lead to “deferred calories” that make us consume more than a full-sugar version would have.

For many years, there have been hints that people who drank sugar-free sodas ended up gaining more weight than those who didn’t. (Travis Saunders described some of this evidence at Obesity Panacea last year.) Guido Frank at the University of Colorado is one of the researchers whose studies help explain this. He fed drinks containing either sucrose (sugar) or sucralose (artificial sweetener) to subjects, who were unable to tell the difference between the two. However:

Sucrose produced stronger activation in the “reward” areas of the brain that light up in response to pleasurable activities such as eating and drinking. Sucralose didn’t activate these areas as strongly… Frank suggests that sucralose activates brain areas that register pleasant taste, but not strongly enough to cause satiation. “That might drive you to eat something sweet or something calorific later on,” he says.

This is still a developing area of research, but it seems highly likely that there’s no (calorie-)free lunch. You can’t have sweetness without (eventually) paying a caloric cost.

The obvious question, then, is whether you’re better off drinking diet soda or full-sugar soda. I’ll join with Travis Saunders in suggesting that you keep consumption of either to a minimum (though, as with most “bad” foods, it should be fine in moderation). But if I’m choosing between the two, now that I know that the overall caloric hit will be about the same for regular and diet soda, I’d rather drink the real thing.

[Thanks to Selam for the tip!]