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Karl Etzel

Karl Etzel

Father, human performance nut, business strategist and GM, trail runner, cyclist.

Tymewear data - Part II
Dec 11, 2025

Tymewear data - Part II

Karl Etzel
Karl Etzel
Breathe, Measure:  Tymewear, Part I
Sep 10, 2025

Breathe, Measure: Tymewear, Part I

My experience setting up and testing with a novel breathrate sensor

Karl Etzel
Karl Etzel
September 2025
Sep 04, 2025

September 2025

Foot injury, Whoop v. FDA, Protein quality, AI Psychosis, REDs & LEA

Karl Etzel
Karl Etzel
Death Ride 2025
Jul 23, 2025

Death Ride 2025

Details on my training and completion of this iconic California bike ride in Markleeville

Karl Etzel
Karl Etzel
May 2025
May 18, 2025

May 2025

Death Ride, Hematocrit, Greenland, Energy Demands of Ironman

Karl Etzel
Karl Etzel
March 2025
Mar 12, 2025

March 2025

Food satiety, vector stores, heat training, TeenTrainer progress, clock wars

Karl Etzel
Karl Etzel
December 2024
Dec 06, 2024

December 2024

Epic roads, CLM's, TeenTrainer, Strava API, Bike upgrades

Karl Etzel
Karl Etzel
September 2024
Sep 18, 2024

September 2024

Leadville record, pre-workout, creatine, heat training, bike saddles, Antarctica

Karl Etzel
Karl Etzel
August 2024
Aug 19, 2024

August 2024

Lactate testing, coffee bioactives, creatine sources, obesity meds

Karl Etzel
Karl Etzel
July 2024
Jul 30, 2024

July 2024

Work update, trail running adventures, running tech & injuries

Karl Etzel
Karl Etzel
Topics on my mind across many domains.

Karl Etzel's Newsletter

Topics on my mind across many domains.

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