Runners Don’t Forget The Carbs
Muscle glycogen is the primary fuel source for most sports!
- Marathon - (65% VO2max) 60% Carbohydrate (CHO) 40% Fat
- 10KRun - (85% VO2max) 75% CHO, 25% Fat
Marathoner’s Diet
- CHO - 60-70% of cal (limited storage)
- Fat - 25 -35% of cal (abundant storage)
- Protein - 10 -18% of cal (need adequate amount - 1.2 g - 1.76 g per Kg of body weight)
Why Carbs?
- Fuel for brain
- Preserve proteins
- Aid fat metabolism
- Provide bulk and fiber
Back to back training days can deplete your glycogen (CHO) stores. This could result in a decrease in performance.
- High intensity aerobic exercise (1 hour) depletes > 50% of the liver glycogen
- 2 1/2 hours depletes liver and muscles glycogen
CHO Recommendations:
Approximately 60 - 70% of daily caloric intake
- 45 - 55% as complex CHO
- 10 - 15% as refined CHO or simple sugars
Approximately 500 - 600 g CHO/day to replete glycogen stores
Needs based on training time
- 1 hour/day - 6 g CHO/kg body weight
- 2 hours/day - 8 g CHO/kg body weight
- 3 hours or longer - up to 10 g CHO/kg body weight
Source: Miriam Nelson, PhD, John Hancock Center for Physical Activity and Nutrition
Friedman School of Nutrition Science and Policy Tufts University
Although I got a late start, I’ve been a serious runner since 1994. I ran my first marathon in 1995 on my 30th Birthday. It’s been my goal to run the Boston Marathon since then. I missed qualifying by 12 minutes that year. I needed to run 3:40 and ran 3:52. Running in the most prestigious marathon, is the ultimate for most runners. The fact that you have to qualify, only fueled my competitive juices.
Over the next 9 years I ran 6 more marathons. I love running so much that I became a 
4 comments:
great summary lisa. you really need to know this stuff when you start to get serious. if you don’t get the diet right, its almost like wasting your time training. diet is a bigger proportion of success than I first realized. it can be a challenge to track your food intake. it requires reading labels and keeping a food log - when you are figuring it out, take a pad with your and record everything you eat and (if known) how many grams carbs/protein.
for me, 830 grams of carbs (10gx83kilo) is really a lot of food and if I don’t eat healthy stuff, it can include waaay more fat than I should be eating.
you rock lisa, keep on rollin’
Thanks, you are so full of information!
I cut out red meat the beginning of December. I have been focusing on getting more carbs, water and less sugar. I feel better and I’ve lost a few pounds. I’m not super precise about grams of carbs, but I’ve noticed a difference in my performance.
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