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  • Don’t Get Fooled Again – Workout Recovery

    I’ve decided to start a series titled “Don’t Get Fooled Again” to help endurance athletes sort out information that is true or false at face value. I’ll post a question in the morning on Gale Bernhardt Consulting Facebook and have people weigh in with comments. I’ll comment later the same day on Facebook. I’ll store the series here on my blog so it is easy to find.

    Let’s begin with workout recovery:

    In order to optimize performance and recovery, athletes need to continually load and reload muscle glycogen stores. This process cannot happen on a low-carbohydrate diet. (True or False?)

     

    This should be fun!

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    False.  Athletes on low carbohydrate diets have shown that they can indeed reload muscle glycogen stores on not only a low-carb diet, but on a ketogenic diet (very low carbohydrate diet.) More below, but if you want the short of it - glycogen levels were IDENTICAL between the high-carb and low-carb athlete test groups.

    In this 2015 presentation by Professor Jeff Volek, he describes the results of a very interesting study he did comparing 10 high-carb (60% carb, 15% protein, 25% fat) and 10 low-carb (10%-12% carb, 20% protein, 70% fat) elite male ultra-runners. I think the whole thing is worth watching; but, if you don’t have time and want the answer to the question at hand, you can get it in about 5 minutes.

    If you begin at time mark 21:26, you can see that the runners eating the very low-carb diet (LCD) burn fat at a much, much higher rate than athletes on a high-carb diet (HCD).

    At time mark 23:25 Professor Volek notes that the two groups are both performing at very, very high levels. This is evidence that people can consume two very different diets and both groups can be quite successful – athletically. (We’ll talk about health later.)

    Time mark 23:50 Volek notes that they measured many metabolites in the blood and glucose levels in the two groups was “surprisingly NOT that different.”

    At time mark 25:23 Professor Volek says, “This is really new data that was very shocking to me because I would have bet my house that the glycogen levels would have been lower at rest (in the LCD group) and there would have been a significant attenuation of glycogen use during exercise. But we observed just the opposite. The glycogen levels were IDENTICAL between the low-carb group and the high-carb group.”

    Time mark 26:00, he notes “Two hours of recovery, they (both groups) had the same resynthesis of glycogen – despite the fact that we actually, I didn’t mention it, we gave the HCD group a high carb (recovery) shake. Not high calorie shake, but we felt like we had to give them something, so we gave them a little bit of glucose at the end. We gave the low-carb group fat, equal calories (compared to the high-carb group.) So that makes it even more surprising that these low-carb guys are able to resynthesize glycogen WITHOUT ANY PROVISION OF CARBS, really, post-exercise. I’m still scratching my head over this.”

    Volek’s video was recorded in 2015, and he is a traditionally trained physiologist and registered dietitian. But he looked at the data rather than assuming his textbook learning was the only answer. Physiology textbooks are most certainly being rewritten as I write this blog.

    If someone is saying that glycogen stores cannot occur on a low-carb diet, they are not aware of – or they are intentionally ignoring – research that Volek and others are publishing.

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