Marathon training: Carb loading and the marathon weight gain

When you’re training for a marathon, you must lose loads of weight, right?

Er – not necessarily.

Marathon training is a funny thing. It’s not just running. It takes over your whole life. Every day, your next run and the run after that is on your mind. You need to work round them and fit them into your life and that isn’t easy.

And you have to make allowances with what you eat.

When exercising, it is the food which you’ve eaten the day before which fuels you. When you’re running 18, 22 or 26 miles, that’s an awful lot of fuel you need to take on, which is where carb loading comes in. You really do need to eat more on the day before (and the day before that) a big run.

So life becomes one big long round of carb loading, recovery and doing it all over again. And that’s not really conducive to losing weight.

Gaining weight while marathon training is not unusual. I’ve even read that some people won’t run a marathon for fear of gaining weight. (In my opinion, people like that need to have a long hard look at themselves and rethink their priorities.) But you do need to get the balance right to avoid gaining too much weight. And it’s not easy.

I’m not joking when I say that my body looks different nearly every day. I will have days when I think ‘How did I get that thin?’ and other days when I’m bloated or have visibly gained fat. Then just as soon as it has appeared, so it will disappear again, only to reappear a few days later.

Like most women, my weight tends to fluctuate by two or three pounds and, allowing for the fluctuations, I’m about two pounds heavier than before I started marathon training. I reckon that’s a pound of extra muscle and a pound of additional carbs I’m lugging round in my belly, waiting to be burned off on an 18 mile run.

I’m pretty sure seasoned marathon runners won’t go through this roller coaster. They will have the whole carb loading and recovery thing totally nailed, but I’m a newbie and I’m just going with the flow. I haven’t got it right just yet. I suspect it will take several more marathon training cycles to get it right (ask me in a few weeks if I’m ever going to do it again!), but I’ve got it just about good enough.

It really doesn’t matter if I look skinny one day, bloated the next and flabby the next. My body is being pushed to the limit right now and I’m doing my very first to fuel it as well as I can.

I might not be getting it quite right, but I’m getting it good enough for me.

Spaghetti, Carb loading, Carbs, Training, Marathon training, Carb loading and the marathon weight gain

Photo by Krista Stucchio on Unsplash

Author: Sarah Mummy

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  1. Oh I’m so glad this is a thing, I had no idea! I often try to run more to lose weight but I don’t think I really fuel more before long runs, so I end up eating more afterwards because they’ve made me hungry so I don’t lose weight. I’m attempting both weight loss and marathon training at the moment so I do hope they don’t counteract each other! It sounds like you’ve got it nailed, I totally agree that it really doesn’t matter about how you look, you’re going to ace the marathon and that’s what matters.

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    • Thanks very much, that’s definitely what matters! I am terrible for eating too much after a run. I basically eat every hour for about five or six hours. My husband has struggled in the past with trying to lose weight while training for a half marathon – and ended up hitting the wall badly during a half marathon. He’s a lot more careful now to eat enough beforehand. x

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  2. I still need to seriously work on fuelling – I can get very ill after and it is especially if I run faster. Sounds like you have everything under control.

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    • Thanks very much, I think I do, but there was some trial and error involved! You might be getting ill because you haven’t had enough to eat or drink while running. I’ve always been fine running 13 miles without anything to eat, but knew I would have to do things differently for a marathon.

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