I’m an author and journalist in Toronto. My primary focus these days is the science of endurance and fitness, which I cover for Outside (where I’m a contributing editor and write the Sweat Science column), The Globe and Mail (where I write the Jockology column), and Canadian Running magazine. I’ve also covered technology for Popular Mechanics (where I earned a National Magazine Award for my energy reporting) and adventure travel for the New York Times, and was a Runner’s World columnist from 2012 to 2017.

My latest book, published in February 2018, is an exploration of the science (and mysteries) of endurance. It’s called ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance. Before that, I wrote a practical guide to the science of fitness, called Which Comes First, Cardio or Weights? Fitness Myths, Training Truths, and Other Surprising Discoveries from the Science of Exercise, which was published in 2011. I also wrote Big Ideas: 100 Modern Inventions That Have Transformed Our World, in 2009.

I actually started out as a physicist, with a Ph.D. from the University of Cambridge then a few years as a postdoctoral researcher with the U.S. National Security Agency, working on quantum computing and nanomechanics. During that time, I competed as a middle- and long-distance runner for the Canadian national team, mostly as a miler but also dabbling in cross-country and even a bit of mountain running. I still run most days, enjoy the rigors of hard training, and occasionally race. But I hate to think how I’d do on an undergraduate physics exam.