Struggling to set macros for marathon training

lporter229

I am currently training for an October marathon. I am reading Matt Fitzgerald's Racing Weight and have realized that, according to him, I have been woefully deficient in my carbohydrate intake. I am 5'0, 102 pounds and run about 50-55 miles per week. He suggests that I should be consuming at least 300g of carbs to support this amount of training. Over the past two weeks, I have averaged about 210g per day. I have tried to adjust my macros to increase my carb intake, but in order to get sufficient protein, that leaves me with only about 45 g of fat per day. Based on my dietary habits, this is not going to happen.

I eat pretty well, particularly in regard to the rest of his plan which emphasizes eating fresh, nutrient dense foods. I have my calories set to 1950/day (based on TDEE, which includes my exercise calories) and I have been maintaining my weight for quite a long time. I do allow myself to go over on calories within reason because I know that those long runs need to be supported. I do not feel sluggish or that I have poor performance. Also, I can not eat gluten due to health issues, so getting the normal amount of carbs can be a challenge. Two weeks prior to my marathon, I always force myself to load up with carbs, usually about 300-350g/day, but doing this on a regular basis would be hard.

The way I see it, I have 3 options:
1. Continue with my current regimen and ignore Matt Fitzgerald. However, the dude supposedly knows his stuff and his "80/20 Running" was a godsend for me. Maybe I have room for improvement if I listen to him.
2. Increase my overall calorie intake so that I am eating 300g of carbs per day and still able to eat the amount of fat and protein I am currently eating. However, I would probably end up gaining weight, which could also hurt my performance.
3. Increase my carb ratio and lower my fat intake, which would force me to make very big changes to my eating habits.

Just wondering if anyone has any thoughts or advice on this situation...

patrikc333

I am training for a marathon as well and I ended up sacrificing a bit of my fat for carbs and protein (when looking at the overall daily cal allowance)

I average 460g per day, (but I'm taller and heavier than you) - this based on maintenance cals MFP gives me, + all my exercise (including ~80 miles per week running)

1950 cals looks quite low to me, but if you are not losing, it must be pretty accurate, so I won't increase the cal intake (but I'm not sure how much you go over as you said, could it be that you balance a potential deficit when you go over?)

in the end, I'll go for option 3, or better for option 1, if what you are doing works for you, then why change it?

lemurcat12

If you are curious, I'd experiment with it and see what you think. You can always shift back if you don't like it.

I have a couple of near-term races so don't want to shake anything up and then will seriously try to get the last 5 lbs off, but I'm thinking of trying out a few different levels of carbs when training over the off season (and for a Marathon in Jan) to see if I feel or do better with more carbs.

lporter229

Thanks for the input guys. patrikc333, you are right, 1950 is not that many calories when it comes to marathon training, but I am 43 yo and, despite being very active, age does catch up. I averaged my calories over the last few weeks and it looks like I am @ about 1980/day. I am pretty lazy in weighing/measuring because I know I have room for error. Maybe if I up my calorie goal, it will force me to be a little more accurate and I might find that I have room for a few more of those carbs.