How to Carb Cycle Your Diet As a Runner

Carb cycling may sound technical, but really it’s just a practice of cycling your carbs up and down in cadence with your running schedule.

Let me explain.

If you’re a regular runner, you might train 4 to 5 times per week. In that period you will have days where you run different lengths and speeds, so basically you’ll have long runs, short runs, hard runs and easy recovery runs.

If weight loss is your goal in all of this, then you might want to consider reducing your calories and your carbs on the days that you’re doing shorter, easier runs, and on your rest days.

So your running schedule might look like this:

• Monday - Off
• Tuesday - 40-minute easy run
• Wednesday - cross train (yoga or upper body weight lifting)
• Thursday - 60-minute run
• Friday - Off
• Saturday - 90-minute run
• Sunday - easy 30-minute recovery run

Low Carb Days

On Monday, Friday and Sunday, since you’re doing less work in your training, you can afford to take in fewer calories, so those are the days you’d reduce carbs and calories.  On those days, try doing this:

Protein: Your body weight x 1.2 = (so for a 140lb person, that would be 168g)
Fat: Your body weight x .5 = ( so 70g for 140lb person)
Carbs: Your body weight x .4 (56g for a 140lb person)

If we do a little more math here, knowing that 1g of carbs and proteins = 4 calories and 1 gram of fat = 9 calories, then we know that on a low carb/calorie day, you’re eating 1,526 total calories, mostly fat and protein and a little bit of carbs.

High Carb/Calorie Days

On the days that you have those long runs planned, you’ll want to eat more carbs and about the same of everything else. Here’s how this would break down:

• Protein: Your body weight x 1.2 = (so for a 140lb person, that would be 168g)
• Fat: Your body weight x .7 = ( so 98g for 140lb person)
• Carbs: Your body weight x 1 (140g for a 140lb person)

Given that same math, that’s around 2,114 calories total. Now, these are just guidelines because if you’re running more or less, then you will need more or less calories, but you get the general idea that your carbs should go up or down based on the distance you plan to run in a day.

The key to getting this right is tracking your calories as best you can in a macro counter like MyFitnessPal.com. Without a clear picture of your intake, you’re going to have a hard time staying on track. So even if you only track for 2 weeks until you know exactly what you’re eating on the regular, then you’re well on your way.

So, what might a high carb day look like?

In practice, this might look like a having a bowl of oatmeal or 2 slices of gluten-free toast before a long run and adding half a baked potato at dinner instead of just meat and veggies. Or, maybe you save up all your carb calories for a pizza? Your choice. That’s the beauty of flexible dieting. The key is to stay within the boundaries highlighted above.

Pro Tip: On high carb/calorie days, you want to have a good majority of your carbs before your long run so that you’re fueling optimally. That said, it might be better to think about your carb cycles in 24-hour increments rather than the time you wake up to when you go to bed. For example, your high carb/calorie day can start at noon on Saturday and you can have carbs that night (pizza?) and perhaps a bowl of oatmeal before your super long run the next day, but after your run (let’s say you run from 11 am to 12:30 pm) you might want to cycle into a medium carbs for the following 24 hours. Hope that makes sense.

Want the scientific skinny behind carb control with endurance exercise for maximum fat loss?  I highly recommend this book.