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From Fellrnr.com, Running tips
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* The endurance test was not to exhaustion and is more of a long training run. The intensity was 64% of [[VO2max|V̇O<sub>2</sub>max]], which a pace of about 100 seconds/mile slower than marathon pace.
* The biggest problem with interpreting the endurance test is that not only are the two group of athletes different, but the groups were given a shake with different nutrition 90 minutes before the test. It's impossible to know what variation between the groups results is due to prior training and what is due to the shake.
* The low carb shake consisted of heavy cream, olive oil, whey protein, walnut oil, and strawberries, which is seems to be a good choice of ingredients. Constructing a shake that is low in carbs but palatable is tricky. * The low high carb shake is more problematic. : It also consisted of the heavy cream, olive oil, whey protein, walnut oil, and strawberries of from the low carb shake, plus bananas and agave syrup. The high carb shake is nothing like the nutrition a reasonable athlete would consume. The carbohydrate in agave syrup is 67-90% [[Fructose]]<ref name="Figlewicz-2009"/><ref name="SRINIVASAN-1954"/>. This , and this level of Fructose makes this a remarkably poor choice for athletes (or anyone else) as it is extremely slow to digest. The inability to digest the Fructose can be seen in the way the high carb athletes' blood glucose does not rise. It's impossible to know if this was simply a poor choice or if it constitutes an intentional bias intended to promote low carb nutrition.
* During the endurance test the low carb athletes burned more fat and less carbohydrate than the high carb athletes. Normally an increased fat burning capability is seen as a good thing in athletes as it helps preserves [[Glycogen]], which is typically a limiting factor in endurance events. However, both groups burned through similar amounts of Glycogen. The test was a fixed 3 hour run, so there's no way of knowing if either group would last longer before reaching voluntary exhaustion, but it seems likely that Glycogen levels would limit both groups equally. It also seems likely that a reasonable source of carbohydrate for the high carb group would have resulted in them using less Glycogen than the low carb group. (The study noted that the low carb athletes burned more Glycogen than the estimate for their total carbohydrate burn, which is rather strange.)
==Non-Ketogenic Low Carbohydrate Diet (NKLCD) and Exercise==
<ref name="Phinney-2011-p31">Phd Stephen D. Phinney MD, Rd Jeff S. Volek Phd, [http://www.amazon.com/The-Art-Science-Carbohydrate-Living/dp/0983490708 The Art and Science of Low Carbohydrate Living: An Expert Guide to Making the Life-saving Benefits of Carbohydrate Restriction Sustainable and Enjoyable], 2011, publisher Beyond Obesity LLC, isbn 978-0-9834907-0-8, Page 31</ref>
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