April 18th, 2012 11:05am - Posted By: Adam St.Pierre, MS
Of late there’s been a lot of attention paid to different diets/philosophies on food. Among the popular philosophies out there are the Paleo diet, the Atkins diet, the Zone diet, the South Beach diet, the Mediterranean diet, and more. One interesting similarity these diets have is a higher proportion of fat and protein than the typical American diet which is very high in carbohydrate. In reading research studies and speaking with people who’ve tried various dietary modifications one thing stood out; people who eat lots of carbohydrate (60+% of total daily calories) tend to burn carbohydrate during exercise and throughout the day whereas people with less carbohydrate consumption (50% or less of total daily calories) tend to burn more fat. Then along came the idea of Metabolic Efficiency Training, put forth primarily by Bob Seebohar, MS, RD, CSSD, CSCS (http://www.fuel4mance.com). In this method of eating, you focus on proteins, healthy fats, fruits, and vegetables, and only consume whole grains during times of heavy training (avoiding refined carbohydrate for the most part). He does NOT propose a low carb diet, rather that an athlete consumes carbohydrate from natural sources. He’s had success with a variety of athletes with this method, both short and long term. I wanted to discover for myself:
Would a low carbohydrate diet decrease the reliance on carbohydrate during exercise?
Is a low carbohydrate safe/sustainable for an athlete during times of heavy training?
Does it need to be sustainable for long or will a short term modification affect long term changes?
These are the questions I am seeking to answer with a 2 week self experiment.In this experiment I will be consuming as little carbohydrate as possible, doing a normal amount of base training, and track my metabolic responses via F.U.E.L. testing. At the top of this post is my F.U.E.L. graph from March 30, 2012. This test was to be my baseline test, please note that I had been consuming a low grain diet (no pasta, rice, or bread, with a few exceptions- I love Pizzeria Locale!) for about 3 months prior to this test. Note that may total caloric expenditure was similar to the 2010 test, but that I burned more fat at lower intensities, and this fat burning persisted at higher intensities. Unfortunately, even with this improved fat metabolism during exercise, my caloric needs from carbohydrate would still make ultra-running success difficult to fuel.
Below is my daily journal, as well as the results from my F.U.E.L. test after 1 week of drastically low carbohydrate intake.
Low-Carb Diet Day 0- Had a good long run out by the Rez with HTS. Legs a little tired from yesterday’s long hilly run with Craig Howie and Rob Pickels. Celebrated with a high carb dinner (Risotto) and prepared for 2 weeks of low carbs.
Low-Carb Diet Day 8- FUEL test in the morning. WOW! Massive increase in fat burning across the board. Went from burning 45% carb, 55% fat at 8min on March 31, to 90% fat, 10% carb at the same pace today! Total caloric expenditure was the same, 980 calories per hour, but only needed to get 85 calories from carbohydrate! In theory that means I could run for hours at 8 min pace eating less than 1 gel per hour! Very excited about these results. Had some nuts for breakfast after the test. Salad for lunch with smoked salmon, bacon, goat cheese, pepitas, Udo’s oil, protein powder, and chia seeds. Ran with Alison after work. Scallops, bacon, scallions, swiss chard, and just a little sweet potato for dinner. Based on these drastic results, I’ll add some carbohydrate back for a few days then simulate a race on Friday. I’m wondering if this could be a “crash diet” for a week before an ultra and want to see what will happen if I eat some fruit and veggie carbs over the next few days (maybe some yogurt too) and treat Friday morning as a race, have breakfast then run on the treadmill for 1-1.5 hours with the mask, maybe even take a gel 20-30 minutes into the run to see what happens to RQ with carbohydrate intake.
I'll post those results, and a discussion of the 2 weeks as a whole, next week! I'd love to hear your thoughts, questions, and opinions, leave a comment here, or on our FaceBook page!...
Posted in: None
View / Add Comment | 1 Comment(s) | Rating: 4 of 5 | Share: Twitter, Facebook, Google +