From last spring:

I just ran the Napa Marathon last Sunday. I had a great first half, everything according to plan, despite the 34º at the start line with a constant drizzle. Around mile 16, there were a few signs that my body was not happy in a way I had not experienced before. Muscles around my hips were on the edge of cramping, and calves started to lightly cramp. By mile 18, I had to stop and stretch. It basically got worse until I was run-walking for the last four miles. A cramp suffer fest.

I worked hard during training and broke through many plateaus, both physically and mentally. I missed one workout in the 20-week cycle. Despite this, things can go wrong or not as planned. What happened? I’m putting my money on the fact that I was seriously sodium depleted. What would I do differently for the next marathon and training cycle?

Do better with electrolyte/sodium replacement throughout the training cycle. I majorly fucked this up. I noticed that I was peeing a lot during the last three weeks; it was taking a lot more effort to hit target times; my legs were sluggish; my calves muscles were unusually twitchy and active; and now that I am writing this, I believe they were signs that my body was trying hard to balance my low sodium levels with a diet that is naturally water rich (fruits, vegetables, whole grains, legumes). Though the science points to the health of low-sodium diets, when you deplete yourself through exercise several times a week for month after month and follow the healthiest diet on the planet, your sodium levels may suffer.

So I went in to the race depleted*, and it just got worse—cramps/shitty end. A big mistake that could have been really bad. Thankfully, it was remedied when I went for physical treatment for my calf cramps. By looking at the hyper-electric shitshow my calves were doing, the medic said that he saw this in summer races and that sodium depletion was the cause. A low-sodium diet and endurance running don’t mix well if you do not replace sodium after long or hard efforts lasting more than an hour, i.e., speed work and long runs, especially if you’re a salty sweater.

The medic fed me some soup and a “bolus” of an electrolyte drink with 1 TBSP of salt (6000 mg). He said he’d give me a bit more, but I’d probably throw it up. I sipped it while he worked on my legs. I started feeling better, and the cramps and calves started calming down within 15 minutes. I’ve read a lot since then, and there is a lot of controversy about electrolytes/sodium and endurance. But it seems like the most plausible explanation for my disappointing last 8 miles. I’m a salty sweater, and on long bouts you can lose more sodium than you replace if you eat a sos whole-food plant-based diet.

So, for now, salt stick caps are back in my running bag for the next one.

My A plan didn’t work out this time. My coach said it was always wise to have a B plan. I had one: finish.

But I know I can do it better.

End note: Maybe sodium depletion really played a significant role, but I discovered a few weeks after the marathon that the gels I was using were deceptively labeled, which could explain, or at least partly explain, my gradual training decline and depletion. It turns out that when I thought I was ingesting 45g of carbohydrates in a 180 kcal gel, after lab analysis it was 18g of carbohydrates in a 75 kcal gel. I should have been consuming 3 vs. 1 to properly fuel my long and challenging workouts.

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