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The impact of 100-mile training on the body


A simple blood draw and you are on your way to getting useful InsideTracker data.

By Henry Howard


I purposefully scheduled my most recent InsideTracker blood draw at the peak of training for my 100-mile race this summer. While I knew the data would be jacked up from the physical stress, I wanted to be able to see how the training affected my key biomarkers as compared with the previous test March 27, when I was just finishing training for my April marathon.


Regular InsideTracker tests allow me to analyze how my training, nutrition, recovery and other factors impact my overall health. InsideTracker not only provides easy-to-grasp data but offers customized recommendations for improvement.


Since I have been using InsideTracker regularly, I have improved my vitamin B12, cortisol and other key health categories. After each blood draw, I receive easy-to-understand data for more than 40 biomarkers scored in three categories — optimized, needs improvement or at risk. From there, I receive science- and nutrition-based recommendations on how to improve certain areas. The recommendations are customized to my diet, goals and more.


For ultra runners, marathoners and even those who enjoy doing 5Ks, I’d recommend looking into an InsideTracker test. It’s the best way to get a science-backed analysis of your health. Get 20 percent off any InsideTracker test with this link.


InsideTracker's charts are easy to read and provide additional links to dive deeper.

How I read InsideTracker data

After each InsideTracker test, I review the score, analysis and recommendations, then create a to-do plan for myself. I also publish the action steps I will take to hold myself accountable and so that the next test should yield better results.


After my test in March, I set my intention to improve three key areas. Here’s how I fared:


Improve sodium level. The previous test showed that my sodium level had plummeted from 134 to 130, deep in the at risk zone. The July test showed a reversal, climbing to 132. Much more improvement needs to happen, though, as the optimized baseline is 137.


• Reduce potassium level. After back-to-back tests in the red (at risk) zone, I improved my potassium levels, dropping from 5.5 to 5.2 in the needs improvement category. That’s good progress, especially considering all the training. Next goal will be lowering it to the optimized area, which is 3.6 to 4.8.


Keep boosting white and red blood cell counts. The March test indicated gradual improvement for both of these markers, which are just below the optimized line. The July results shows that the white blood cell count (WBC) declined while the red blood cell count (RBC) improved. White blood cell count is an indicator of inflammation throughout the body. InsideTracker provides some thorough information about WBCs, including tips to improve these readings. My RBC score was 4.1 in the optimized zone, far better than the past three tests which were all in the at risk zone. Red blood cells carry oxygen from the lungs to tissues throughout the body. A healthy number of red blood cells helps ensure your body receives the oxygen it needs to function properly.


InsideTracker has helped make me healthier.

What does other InsideTracker data show

Overall, my July test revealed 34 biomarkers in the optimized zone, down one from the previous test; nine in the needs improvement area, up one; and seven in the at risk category, one more than the test in March.


That tells me that during this surge in training, where I was asking much more of my body, I was able to stay relatively stable in these key biomarkers. Yet, there is still room for improvement in critical areas.


Here are some key takeaways:

• As noted previously, I still need to improve my sodium balance and white blood cell count.


• My cortisol level has risen from 23 to 26.2, which is not a surprise given the peak of training I was in. However, with the optimized level set at 4 to 22, I have some work to do.


• After my vitamin B12 spiked in the October 2022 test, I started using a new supplement but backed off to five days a week instead of daily initially and more recently I am only taking it a few times a week. I’ve lowered my B12 level from an extraordinary high of 1295 to 597 and now to 635, comfortably in the optimized zone.


While I still have work to do, I’m grateful that I am able to use InsideTracker’s easy-to-understand, customized, science-backed data to improve my health. That’s true even when I am in the peak of hard-core training for this year’s big race.







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