How Many Carbs?

Q: Tony, I know you always tend to advocate that people fluctuate their calorie (and as a result, their carb intake) on training days compared to non-training days. Can you elaborate on this a bit? I am trying to lose some fat and don't know how many carbs I should be eating per day?

A: You're absolutely correct. I do HIGHLY advocate that people try to fluctuate their caloric intake to correlate with their daily activity....especially if one's goal is fat loss. For a quick primer on my thoughts dealing with carbohydrates, check out this article that I wrote for wannabebig.com.

Carbohydrate Conundrum

However, if you have the attention span of a kid with ADHD (it is a long article), here are some quick thoughts:

1. It makes no sense to me to keep calories the same on non-training days, as on training days if one's goal is fat loss. You need to provide some sort of caloric deficit in order to burn fat. It stands to reason that you won't be expending as many calories on non-training days, so you won't "need' as many calories.

2. For FAT LOSS, low(er) carbohydrate diets trump high(er) carbohydrate diets in every way...even if caloric intake is kept constant. Technically, low carbohydrate diets would constitute any diet where carbs are kept to under 100 grams per day. I think people tend to be a bit too carbo-phobic though. To keep it simple:

Non-training days: keep the bulk of your carb intake to the first 1-2 meals of the day. Rest of the day should be focused on green veggies and protein/fat.

Training days: Pre/Post training drink, followed by some starchy carbs with the first whole food meal about an hour later.

It's important to realize that the body is going to burn whatever fuel is most readily available. If you're eating carbs all day, your body's ability to burn BODY fat is ZERO (even if you're hypocaloric). This is why I find it so absurd that dieticians still advocate diets that are upwards of 60% carbs for fat loss. They don't take into consideration the HORMONAL effect that it has on the body.

3. Substrate utilization has been shown to NOT be effected during the post-training window, even when carbohydrates are ingested. Read: your body will still be burning body fat even if carbs are ingested post training:

Coyle, et al. Muscle glycogen utilization during prolonged strenuous exercise when fed carbohydrate. J. Appl. Physio. 1986; 6: 165-172