Pre-run fueling is critical for sustained performance. And stable & sustainable fuel sources are key.

Currently testing how certain variables impact my glucose levels with @supersapiensinc

Here are the CGM results from 2 smoothies

The left smoothie increased my glucose from 104-152 mg/dL (18% of the duration of this food event was spent above 140 mg/dL, which is known to cause cellular damage!)

The right smoothie 108-118 mg/dL

Also notice the post-event drop. Within 30 minutes of finishing both smoothies, my glucose spiked and returned to levels lower than I was at before the smoothie

Left low: 77 mg/dL
Right low: 85 mg/dL

This "reactive" scenario is not what I want.

If I'm about to go on a long run, I don't think either smoothie is a good option for me — my glucose (immediate fuel) is now too low when I thought I adequately "fueled up"

Ideally, I'd fuel with something that brings me up and keeps me up — possibly a different fuel type, less total carb, or longer feeding duration.

Here, I'm looking to limit the steep spike, which triggers a significant insulin rush and brings my glucose levels too far down.

Glucose Variability

Essentially the SD, or degree of up and down movement of my glucose levels, measure 0-30 mg/dL.

Left smoothie: 17
Right smoothie: 6 (more stable!)

For me, this helps discover stable fuel sources.

A steep spike triggers the hormone response and subsequent instability.

A more gradual rise doesn't — preventing physical/cognitive performance degradations and providing more sustainable fuel over time

Average Glucose

Left: 122 mg/dL (high!)
Right: 108 mg/dL

Both smoothies included strawberries, cashew butter, raw honey, chia seeds, and almond milk.

The difference? The right smoothie also had collagen powder and mct oil

Maybe that prevented the steep spike? Maybe it was my workout earlier that day? Or maybe one of the other factors that impact glucose levels...

Experiential learning continues

Btw this is a new frontier for athletes.

This analysis is based on personal research and experience with fueling. In no way is it a perfect guide for you (or even me!) I'll keep learning and updating with new data and findings.

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