I know that getting enough sleep while I'm marathon training is important. I've been told this many times.
However, as I am now further along in the process, I've been confronted with just how much it affects. Over the past couple of months my need for sleep has grown a lot. I've been sleeping much more deeply, but if I don't log enough hours, getting out of bed in the morning feels like I'm rising from the dead, and then the rest of the day I feel ill and a productive run is nearly out of the question. (Sure, my body can physically go through the motions of running, but I'm slow, can't go as far, and afterward I want to eat the world and fall into a coma.)
With how much wear and tear a body goes through while training for a marathon, this makes sense. I asked my training coach with Team USA Endurance , the official NYC Marathon team for the U.S. Olympic Committee, to tell me more. "The body reaps the training effect from a workout during the recovery phase, not during the actual work. So if you don't recover, you don't actually improve your fitness; you break down and get sick and hurt," says Andrew Allden, also the women's cross country coach at the University of South Carolina.
In a recent SHAPE article by fitness professional and New York Times bestselling author Adam Bornstein , it was made clear just how important sleep is for a healthy body. Lack of sleep makes you crave food, changes your fat cells, can increase risk of injury, and causes muscle loss, Bornstein writes. As if I needed more reasons to hit the hay.
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So how many hours is enough? According to Allden, "Most elite runners who train professionally sleep a lot, like nine to 10 hours per night, plus a nap."
I laugh. Ten hours plus a nap (a nap? hah!) is so far from my reality. I'll be honest: I usually shoot for eight hours per night and end up somewhere around seven. This is a good day. Clearly I have a new priority to focus on, but even with my efforts to get more shut-eye, I'm sure I'll have nights from now until November 3 that I don't get enough. In these circumstances, I had to know what to do if I was scheduled to run.
"If we are talking about a long run in the case of the marathon, I would probably push it back a day if I was missing a lot of sleep," Allden says. "A double-whammy might put one over the edge. And in the scheme of three to four months of training, pushing back a day is not a big deal."
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It's easy to get carried away with marathon training and think you need to work out all the time, clock every scheduled run, and complete every cross-training class—but life can catch up with us. In the case of a busy day, lack of sleep, and a scheduled run, just head to bed. "Remember it is generally not one workout too few that gets you hurt or sick, but the one too many that you should have passed on," Allden adds.
Luckily training and sleep go hand and hand in another way: If you're building muscle and taxing your body with all the miles, you will sleep better. In a 2010 Swiss study , researchers found that chronic vigorous exercising is positively related to adolescents' sleep and psychological functioning—meaning better sleep quality, fewer times waking up, and less time to fall asleep.
So sleep more for better running, and run for better sleeping. You cannot lose. Meanwhile, I'm going to go take a nap.