Saturday's run was a bit of a lethargic mess and it prompted me to do some digging. I have been trying to go low carb high fat (LCHF) for a while now. While I am still way better than most people, I've been struggling with implementing this a bit lately. Some of that is just laziness on my part. Some of it is trying to understand specifically how to apply this type of diet (actually amount of food, serving sizes, what to eat on the run, etc...). And some of it is just trying to trust it -- naturally every lethargic run makes me question whether it can work. On Sunday, I stumbled across a book called The Art and Science of Low Carbohydrate Performance. After reading it over, I am committed to increasing my discipline toward this diet in hopes of making it work better for me. The book is a gold mine of information for the positives and the pitfalls of this type of diet.
There will likely be a blog post in the future as I experiment, but here are some highlights:
- Low carb diets increase the loss of sodium and water, which can result in a negative sodium balance. This is could contribute to my fatigue Saturday. The weekend before I felt great all day and was taking sodium and magnesium pills on the run.
- To maintain Ketosis (the goal of high fat diets), daily intake of fat must be 65-80% of your total calories. Wow!
- My rough targets each day are 400-680 kcals from protein (100-170 g), 1450 - 1620 kcals (165-180 grams of fat, and only a few hundred calories from carbs (less than 50 g). Everything has carbs, so this is tougher than it sounds.
- Here is the key: in a clinical test, the average non-keto (high carb) runner burns about 28 grams of fat per hour (252 kcals) and the average keto (high fat) runner burns 90 g (810 kcals) in the same time. This has HUGE implications on fueling and energy during an ultramarathon. (Both tests were done at 65% of V02 max, which is ideal for fat utilization).
- Both VESPA and Generation Ucan are highly recommended products for aiding in fat burning on race day.
The book is a wealth of knowledge about things like micronutrients and cramping, recovery techniques and debunking the idea that you need carbs to recover, recipes for LCHF athletes, practical strategies for implementing it, research on diets and exercise, etc.... It is well worth the read!
|Thursday||8||Bluffs w/ Tempo|
|Saturday||20||Ridgeline Open Space|
|Total||49||4900 feet vertical|