YOU. SU. LI.
better faster stronger
STOP WASTING EFFORT
START GOING FASTER
We use lab testing, on-road aero work, and technique analysis to turn your training into real speed in the pool, on the bike, and on the run,
Work hard, but work smart.
Metabolic & VO₂ testing for real training zones
Aero & equipment optimization for “free speed”
Technique & movement analysis for sustainable pace
Supportive club culture – no “elite only” barrier
EFFICIENCY IS THE SHORTEST PATH TO SPEED
Because Triathlon is hard enough
Perfect your strokes
Increase your propulsive power with prescriptive drills and exercises
Pacing built from real metabolic data
Simple drills that actually translate to open water
Free Speed
We test, and prescribe training intensity while working to minimize your aerodynamic drag
Field-based CdA, position and equipment testing
Dial-in tire pressure, equipment & fueling
Race-specific pacing models, and training strategies based on your physiology not guesswork
Maximize your economy
Tap into your real potential with running form, power, and physiological analysis
Integration with previous load and injury history
Practical cues, drills, and workouts to improve cost per km
THE YOUSULI PERFORMANCE SYSTEM
Because no two athletes are the same
We offer a wide range of cutting edge physiologic, metabolic, and efficiency tests ranging from metabolic, Red-S screening, to VO₂, lactate and SmO₂ testing to performance tests for athletes and clubs. The goal is to correctly assess strengths and limiters, in order to empower athletes with the right tools to drive efficiency forward.
THE YOUSULI CLUB
A club for ordinary humans doing unordinary things.
Low-barrier membership, high-quality support.
The Yousuli Club is where the numbers meet real people. Group sessions, shared challenges and long-term projects – from first 70.3 to crossing a mountain range.
Membership stays very accessible; you only pay extra for testing or coaching when you actually need it.
Local training meetups and online squads
Shared “epic” projects you can join at your own level
Private community Chat
Priority access and discounts on testing and clinics
WHY YOUSULI
We test, but we don’t drown you in graphs. You get clear training zones, pacing plans, and one-page summaries you can actually us
We look at what’s leaking energy: position, equipment choices, pacing, fueling, movement. The goal is always the same: more speed for the same cost.
No “fast or out” culture. Beginners and Kona-level athletes share the same space, with different plans but the same respect.
What drives us
WORDS FROM THE FOUNDER
FREDERIC SIMON
I’ve spent decades in endurance, hundreds of marathons and ultras, 101 self-supported half-Iron distance days in a row, and more time in the pain cave than I care to admit. That experience, plus formal training in coaching, strength and conditioning, and testing – convinced me of one thing: most athletes work way harder than their results suggest. Yousuli exists to fix that gap between effort and outcome.
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Certified triathlon, strength & conditioning and youth coach
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Focus on metabolic testing, aero, and movement efficiency
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Based in Walnut, California – working with athletes worldwide
