It ain't a resolution! Experience with intermittent fasting as a runner?
January 2, 2018 2:13 PM Subscribe
I'm an intermediate runner looking to spend the first half of this year increasing my pace. To help with that goal, I'm interested in trying out intermittent fasting to help drop my body fat percentage without sacrificing energy on a day-to-day basis. Any experiences with this or similar?
I run 5 or so days a week. My race experience has topped out at halves, and I won't do any longer races this year, so my mileage base is staying where it's at for the time being. I like where my endurance is and now want to work on my pace, which right now is very steady but slower than I want. In addition to mixing in tempo runs and other speedwork, I want to try to decrease my body fat (which is currently around 26%) to help in this goal. Previously, I've lost body fat by traditional calorie counting, but I am not terribly interested in a traditional daily calorie restriction right now, both because I'm OK with my weight (though I realize my body composition will change) and because daily calorie restriction makes me feel sluggish mentally and physically, which I don't want to deal with when I'm also running regularly.
I've already tinkered with my macros over the past few years to lean heavily on protein, good fats, and complex carbs and I'm confident I'm not overeating my TDEE on average - and, again, I'm not concerned with weight loss primarily. I don't have expectations of transforming into a sleek, elite athlete, but I'm curious to see what even a 1-3% reduction could do for my speed.
So! Intermittent fasting is intriguing as a way to cut calories on a weekly average without feeling daily deprivation. I can't find much about this geared towards hobbyist runners particularly. I'm interested in resources, personal experiences, and tips for runners doing intermittent fasting - maybe you've tried this, and you have some! Give them to me. I'm probably looking at the 5:2 variant unless there's some compelling other approach I should try.
Caveats: I had a full checkup most recently last fall, so no health risks in trying this. I'm female, early 30s, and of average height and weight.
I run 5 or so days a week. My race experience has topped out at halves, and I won't do any longer races this year, so my mileage base is staying where it's at for the time being. I like where my endurance is and now want to work on my pace, which right now is very steady but slower than I want. In addition to mixing in tempo runs and other speedwork, I want to try to decrease my body fat (which is currently around 26%) to help in this goal. Previously, I've lost body fat by traditional calorie counting, but I am not terribly interested in a traditional daily calorie restriction right now, both because I'm OK with my weight (though I realize my body composition will change) and because daily calorie restriction makes me feel sluggish mentally and physically, which I don't want to deal with when I'm also running regularly.
I've already tinkered with my macros over the past few years to lean heavily on protein, good fats, and complex carbs and I'm confident I'm not overeating my TDEE on average - and, again, I'm not concerned with weight loss primarily. I don't have expectations of transforming into a sleek, elite athlete, but I'm curious to see what even a 1-3% reduction could do for my speed.
So! Intermittent fasting is intriguing as a way to cut calories on a weekly average without feeling daily deprivation. I can't find much about this geared towards hobbyist runners particularly. I'm interested in resources, personal experiences, and tips for runners doing intermittent fasting - maybe you've tried this, and you have some! Give them to me. I'm probably looking at the 5:2 variant unless there's some compelling other approach I should try.
Caveats: I had a full checkup most recently last fall, so no health risks in trying this. I'm female, early 30s, and of average height and weight.
What kind of paces and weekly mileage are we talking about? In my experience, getting faster has mostly been about spending time on the track and increasing one's pain threshold, but if fasting helps, I'd be interested too!
Definitely ymmv, I'm lactose intolerant, so I can only imagine what terrors would follow in the wake of the aforementioned GOMAD routine.
posted by Borborygmus at 3:33 PM on January 2, 2018
Definitely ymmv, I'm lactose intolerant, so I can only imagine what terrors would follow in the wake of the aforementioned GOMAD routine.
posted by Borborygmus at 3:33 PM on January 2, 2018
I've never done this but I would seriously do research on the effects of intermittent fasting specifically on women. Many of the studies showing the positive effects of IF are studies with only men as participants. The last time I researched this ( a couple years ago) I came to the conclusion that it was bad news for women; now there may be some more research so I don't know what the current consensus is. Here's one relevant link with the caveat that I don't know how well sourced it is.
posted by matcha action at 4:40 PM on January 2, 2018 [3 favorites]
posted by matcha action at 4:40 PM on January 2, 2018 [3 favorites]
I've dabbled in intermittent fasting, not the 5:2 method but simply just removing breakfast and lunch (I run right before dinner). I've gone on my usual 4-5 mile runs after around 22 hours of fasting; I feel better during the fasting and the run but my actual results are slower.
Afterwards I am much hungrier than normal. Based on that, I wouldn't attempt a much longer distance, especially if I was unsure that food was available right after the run. I have a history of not eating after a run and becoming lethargic for a very long time afterwards.
posted by meowzilla at 5:18 PM on January 2, 2018
Afterwards I am much hungrier than normal. Based on that, I wouldn't attempt a much longer distance, especially if I was unsure that food was available right after the run. I have a history of not eating after a run and becoming lethargic for a very long time afterwards.
posted by meowzilla at 5:18 PM on January 2, 2018
I accidentally fasted before a 20k race (didn’t eat breakfast, very light dinner the night before) and didn’t bring any snacks with me. This resulted in dropping my blood sugar to 20 or so and being carted off to the hospital in an ambulance. So...YMMV, but bring some gu packs or something along if you are doing a long run after fasting.
posted by rockindata at 3:36 AM on January 3, 2018 [1 favorite]
posted by rockindata at 3:36 AM on January 3, 2018 [1 favorite]
This thread is closed to new comments.
- GOMAD (Gallon of Milk a Day) and Grazing
- Nutrition in general
YMMV (ha! literally!), I am not that kind of scientist / nutrition is complex, etc.
posted by gregglind at 2:47 PM on January 2, 2018