This is a wildly interesting article over at Science of Us – “I’m Training for a Marathon. So Why am I Getting Fat?” – and with the Nike run in SF wrapping last weekend, it’s timely, too. The big takeaways from the piece can be applied to fitness and weight loss in general, so let’s dive in, shall we?

The article references studies that linked an expectation of serious weight loss for many people training for marathons and half-marathons. Many of these people are working out more than they ever half – five miles today, six tomorrow, a big run of ten or twelve miles last weekend – and while weight loss isn’t necessarily the primary motivator for taking on this particular challenge, you’d figure it would be a happy side effect.

Nope. Roughly three-quarters of marathoners polled for the study either stayed at the same weight, or gained after three months of running four times a week. So what’s the deal?

It’s not more muscle, unfortunately. Even worse, it may be because you’re not really working as hard as you think you are. Ouch. It makes sense for people going for long distances – the focus for many is just on finishing. Add to these long but not necessarily difficult runs a supercharged appetite and the sense that you deserve a treat for all that exercise (or worse, that you better “carb load” with that plate of pasta and some crusty bread), and, well, it’s not rocket science.

Running a marathon, or even a half, sounds impressive. And it is a great feat. You should feel accomplished and proud. Remember that there are many other benefits to fitness than just an aesthetic. Regular physical activity makes you happier, gives you more energy, helps you sleep better and probably improves your sex life, too. There’s the relationship aspect when you train with a group, and it’s satisfying to set mini-goals – a faster mile, upping weights, whatever.

As for weight gain, we’ve been talking the same game for years. It’s allllll nutrition.

So congrats to all you marathoners out there. Cross that one off the bucket list, and come work out with us for a bit of cross-training to really up your game.