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Why I don’t do fasted AM runs anymore

I was recently asked on Twitter if I have any posts on my fasted morning runs. I don’t think I do here on my new website, so thought I’d write one up quick!

For the first half of 2014 I would do almost every non-hard AM run in a fasted state, which means I would not have eaten since dinner the previous evening. I could go and do a 2 hour group trail run at 8 or 9 am and be totally fine until breakfast at 11 or noon.

There are potential benefits to such a practice:
-Doing so may increase the stress of the run. Making the run harder may increase the potential for adaptation.
-Not taking in food before a run may make you better at burning stored fat as a fuel.
-An empty stomach almost reduces your chances of GI issues during the run to zero.
-The practice may help with weight loss, since you’re using stored fat instead of eaten food.

When I was practicing intermittent fasting for much of 2014, I would not eat until noon or later on days that I did not have a hard workout. I would even run in the AM and afternoon before eating, and feel totally fine. No problems what so ever. I was still getting in at least 2000 calories daily with fewer but larger meals.

After my fall half marathon I have ended the practice of intermittent fasting and fasted AM workouts, for a few reasons:

However, there are a number of disadvantages:
-Like elevation may decrease the quality of your training, running fasted may also do the same. Your body is simply held back if it’s not fueled with high octane energy.
-I really really enjoy making and eating breakfast with my wife every morning.
-I feel eating before a run kickstarts the recovery process sooner.

The #1 reason is that my winter goal is to go into the spring being able to comfortably average ~10 miles more weekly. This means I’m currently running about 10-11 hours every week with doubles at least every other day. It’s not the mileage elites do (because I’m slower) but it’s a similar effort level and a similar time spent running. If I’m going to train like the professionals with 10+ hours of weekly running, I need to eat like them as well. I want to make sure I’m fueling and recovering as optimally as possible. Having a small omelet or breakfast burrito before a 1:10 long run means that I’m starting the recovery process right away and getting enough calories throughout the day.

Now, I’m not against fasted runs. Apparently the East Africans do them frequently. If I ran before my wife woke and before we normally have breakfast, I would probably still do them without eating beforehand.