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  Last updated: 5/22/2018

A training advantage for a big breakfast?

I'm an advocate of eating the majority of one's Calories early in the day with just a small salad or light meal in the evening as any Calories, especially carbohydrates, eaten early in the day are preferentially used by your active muscles during the following 3 or 4 hours rather than being shunted into fat cells to be stored for future use. My aim is a 25-50-25 Caloric split for breakfast-lunch-dinner.

Here are a few more details.

This distribution of Calories, with a reasonable breakfast, also helps minimize the risk of a "within-day energy deficiency". The findings in the original study suggest a negative metabolic effect with intra day Caloric imbalances even when the total Caloric input for a full 24 hour period meet your calculated needs..

That study documents "..a significant correlation between the largest single-hour calorie deficits and hormonal disturbances like lower testosterone and higher cortisol." The question is whether that is really a bad thing.

Although studies show animals subjected to fasting and semi starvation diets live longer which may be a good thing in the long run, it is not a successful strategy for an athlete-in-training who needs to keep their body's repair processes at peak efficiency.

If you want to compete at your best, you need to train at your best which includes regular interval training. So anything that limits your interval (or HIIT) sessions is harmful to achieving that goal. The argument is similar to the logic used by athletes who intend to compete at high altitude but need to train at lower altitudes to maximize their ability to stress the cardiovascular system.

There is an ongoing argument as to whether depleting your muscles of glycogen up-regulates fat metabolism which then "forces" the body to improve pathways for fat metabolism. Even if there was proof of this happening (and if there is it is a small improvement) I would suggest that the benefits of limiting interval training as well as the metabolic stresses involved (such as impairing your body's reparative processes) outweigh any advantages from this approach.

The bottom line is that I see few if any downsides to moving a higher percentage of Calories earlier into the day, and only upside benefits.

A recent Dr. Mirkin blog claimed that " Eating Breakfast Helps You Move Faster and Exercise Longer". Although a poor diet might slow you down, as I suggested above, I think the idea that eating a good breakfast will actually add to your speed are an unsupported claim.

First, the complete article that he references.

This is an esoteric study dealing with glucose, insulin responses, and exercise, which I interpret as intended to help design strategies to control blood sugars, not improve exercise performance. So a few of Dr. Mirkin's conclusions from applying them to exercise may be a stretch. (Especially for intense exercise as the article clearly states that their exercise protocol was at 50% maximum potential power levels.)

A few blog comments:

A few more points about breakfast.

Questions on content or suggestions to improve this page are appreciated.

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