Fat adaptation

[kellyp]

I had posted some concerns regarding my training since doing the W30. My endurance has been fine but the hard efforts in sprinting were compromised. I felt like my legs were lead.

I came across the following article and while some of it is hard for me to understand, it does suggest that being fat adapted is not helpful during sprinting efforts but is for endurance. Since I race bikes, it is imperative that I have not only endurance but sprinting strength as well.

I just thought I would like to get some thoughts from others about this.

http://jap.physiology.org/content/100/1/7

[Renee Lee]

kelly, it has to do with metabolic pathways. fat adaptation is good for endurance efforts, because you're operating in the oxidative pathway, where it's most efficient to burn fat for fuel. sprinting efforts, in contrast, operate in the glycolytic pathway, which uses glycogen (glucose + stuff) for fuel. This is why we don't recommend low-carbohydrate for crossfitters or other athletes that live in a glycolytic world...you guys use the glucose and you NEED it.

Try adding some more sweet potatoes or squash into the mix. see if it helps

[kellyp]

Thanks Renee. That is what I have been doing this week. I will see how it's helped this weekend. I apologize for continuing to bring it up but when I see articles like that, it makes wonder again.

I am on day 24 and I do feel great and finally am sleeping better so I really want to get it right so I can continue to stay as W30 as possible.

[B1121]

Just wanted to say thank you for the link to the article.

[Kaleena]

My body has felt like lead too for more explosive bursts during workouts, and even if I'm walking up a hill fast. I will also try more sweet potatoes and squashes. Hope it helps!

[Brad Hefta-Gaub]

If you're really interested in learning about the interplay between athletic performance and nutritional ketosis, I recommend checking out the work of Dr. Peter Attia.

http://eatingacademy.com/nutrition/the-interplay-of-exercise-and-ketosis-part-i

[Brad Hefta-Gaub]

Kelly,

I'll admit, I'm a long distance triathlete and ultramarathoner, so "sprinting" is not something I care to optimize for. I want to develop my fitness to optimize for minimal onboarding of fuel and for very long distance at steady (albeit fast) output. So being fat-adapted is very much an optimal state for me.

Here is another article by Dr. Attia that discusses whether or not fat-adaptation give performance advantage.

http://eatingacademy.com/nutrition/ketosis-advantaged-or-misunderstood-state-part-ii

One other thought. Although it's seems that ketosis does not provide anaerobic power boost, that does not mean that you can't actually improve your sprint performance by becoming fat-adapted.

As a bike racer, you know that power to weight is the holy grail. So as long as you are increasing your power output and maintaining or lowering your weight, then you are by definition improving your performance.

Even if you are primarily operating in a fat adapted state, that doesn't mean you don't have glycogen stores available to you when you need to sprint. In fact, if you are more "fat adapted" for the endurance portions of your ride, you will just have that much more glycogen available to you when you need to "sprint".

In the work I've done with my coach to better understand metabolism he's shown me a chart of what the "ideal" metabolic chart for an endurance athlete looks like. And basically, it's one that has fat utilization at 100% through zones 1-4 and then a sharp drop in zone 5. And even better if the border from zone 4 to zone 5 is pushed out to the highest possible bmp.

When you've become fat adapted to that extent, it means that for the bulk of your metabolic spectrum, you're not using CHO at all... not until you push into the red, and then you have all your CHO stores available to you for your zone 5 effort.

Another great source is Bob Seebohar, who preaches "Metabolic Efficiency". Bob's the former US Olympic Triathlon Team Nutritionist.

Good luck!

-Brad

[Fenderbender]

"Explosive exercising–sprinting- with pure anaerobic respiration produces 6 to 10 seconds of immediate energy with ATP and Creatine Phosphate in the stored in muscles. No glucose is needed, but contractions stop after 10 seconds."

That being said.... You will most likely be doing longer sprints etc and therefore above your anaerobic threshold on a breakaway/ hill climb/ etc and that is when you will be in your glycolic anaerobic zone and need to fuel up on sweet potatoes/ squash/ blah blah..... But the beauty of being fat adapted is, if you stay just below your anaerobic threshold for most of your ride you won't tap into your muscle glycogen stores and then have most in reserve for finishing strong. Win win...

It took me awhile to get used to eating/ training hard on W30 ..... But once I dialed it in I was on fire!!!!

[kellyp]

Thank you Brad and Fenderbender for all of the great information and for taking time to explain things. Makes me more optimistic that I can do this. I just hope I can get where I need to be soon since I have my first race in a month.