UConn's FASTER study - Fat-Burning Machines

I just want to share a really cool study done by UConn in 2015.
https://www.sciencedirect.com/science/article/pii/S0026049515003340

If you don't want to geek out like me and actually look at the data and the results, I'll give a summary..

This study was named the FASTER study (Fat Adapted Substrate use in Trained Elite Runners) and was conducted by Jeff Volek, a physician who has a clinically proven method of reversing type 2 diabetes using the ketogenic diet alone (no medications or surgery).

Background Summary
They took 20 of America's top-performing ultra-marathoners (for instance, Ironman triathletes that are in the top 10%) between 21-45 years old, 10 were "high-carb" athletes who ate 59% carbs, 14% protein, and 25% fat while 10 were "low-carb" athletes who ate 10% carbs, 19% protein, and 70% fats. This study was well-controlled, well-monitored, and definitely very invasive with blood removed, fat removed, and even some muscle clipped and removed for testing. What makes this study unique is that all of the low-carb athletes were on this low-carb diet for an average of 20 months (ranging from 9 months to 36 months) so, in theory, they were fat-adapted. This study really shows what it means to be "fat-adapted" - you won't see these results in high-carb athletes who decide to try low-carb for a day, or even a couple months.

Results
The most significant result of this study is the amount of fat oxidation (or fat-burning) that was done by fat-adapted athletes versus the high-carb athletes.

"The average contribution of fat during exercise in the LC (low-carb) and HC (high-carb) groups were 88% and 56% respectively." Even two hours after the workout, the low-carb athletes showed high levels of fat-burning. They also showed higher levels of ketones (obviously), glycerol, fatty acids, and triglycerides during activity. Lastly, they found no significant differences in glycogen use during exercise or glycogen creation during recovery.

Bottom line, this study really shows how athletes have the "ability to utilize a stable, abundant source of fuel in the form of beat-hydroxybutyrate" by becoming fat-adapted. So it shoots down the idea that you NEED carbs to perform at your peak level. Rather than destroying your body with pizza and coca-cola, you can stay healthy with eggs, a nice fatty steak, and coconut oil being your fuel and be breaking personal records.




Sidenotes

• When looking at the characteristics of the high-carb athletes versus the low-carb they showed that each group was similar height, weight, age, experience, etc. What I think is more than a coincidence is that the low-carb group showed lower body fat percentage (7.8% avg vs. 9.6% avg) even though they have slightly higher body mass (68.8kg vs. 66.5kg). They also showed higher VO2 max, maximum oxygen consumption, (4.46 avg. vs. 4.25). It may not seem significant, but for a high-performance athlete being able to breathe better is definitely a plus.
• Ben Greenfield was actually a part of this study. You can see his results and analysis of the study in these well-written blog posts - "Rewriting the Fat-Burning Textbook - Part 1" and "Rewriting the Fat-Burning Textbook - Part 2".  ​
• By no means does this show that the ketogenic diet is healthier than a high-carb diet. Getting the right nutrients and checking your blood levels as you change diets is important to adjust to what your body is best suited for. Ketogenic diets have shown possibly dangerous increases in triglycerides and cholesterol. What I get most from this study is proof that you can fat-adapt and still perform at just as high of a level without carbohydrates. Almost any nutritionist prescribing USDA's diet will tell you that this is not possible and you need carbohydrates and sugars for fuel.