About PN23

Most teen athletes
train like pros.
They eat like they're guessing.

PN23 closes the gap. Built by a Registered Dietitian, designed for competitive athletes ages 14–18 who train 10–15+ hours a week and want science — not social media advice.

12
Science-backed modules
14–18
Athlete age range
10–15h
Weekly training load
RD
Built by a Registered Dietitian
The foundation

Starting with nutrition.
The rest is coming.

PN23 starts with nutrition because it's the foundation most teen athletes are missing. The platform will grow — training, recovery, mental performance, recruiting. But nothing unlocks without fuel.

12 modules that build on each other. Practical systems. Designed for athletes who train 10–15+ hours a week and need fueling strategies that hold up when life is busy, practices are long, and games are on the line.

Every recommendation traces back to a peer-reviewed citation. No social-media trends. No influencer protocols. No one-size-fits-all macros.

What you get

A system. Not a library.

01

12-module curriculum

Sequenced, not shuffled. Energy, training fuel, game day, recovery. Each module unlocks the next. By module 12 your athlete has a complete system.

02

Adaptive daily targets

Calories and macros that flex with training load, growth, and competition phase — not a flat number. The system adjusts as the season changes.

03

Weekly check-ins

60 seconds on Sunday. PN23 maps energy and recovery against the week's fueling so patterns become visible and fixable.

Who it's for

Built for athletes.
Designed for families.

PN23 is built for two people: the athlete who uses it, and the parent who makes it possible.

The athlete — ages 14–18
  • Trains 10–15+ hours per week at competitive level
  • Competes at club, travel, varsity, or elite level
  • Wants real answers, not recycled social media advice
  • Wants a system that builds — not content to scroll through
The parent
  • Wants to support their athlete's performance goals
  • Needs practical guidance that fits a busy family schedule
  • Knows nutrition is a performance lever, not just a health issue
  • Wants science-backed answers, not whatever's trending
The roadmap — nutrition first
Performance nutrition
Live now
Training optimization
Coming
Recovery & sleep
Coming
Mental performance
Coming
Injury prevention
Coming
College recruiting prep
Coming
Guy Marshall · Founder
Who built this

“I spent years being the teen athlete that trained hard and ate like he was guessing. PN23 is what I wish I had and what every teen athlete needs.

Guy Marshall
MS, RD · Registered Dietitian · Sports Nutrition
RD
Registered Dietitian
CSSD
Board Cert · Sports Dietetics
MS
Sports Nutrition

Guy built PN23 because the information competitive teen athletes need is out there — buried under bad advice, social media noise, and content written for adults. He knows what underfueling looks like on the field, and what changes when athletes start fueling right.

Remove the performance ceiling

Stop underfueling.
Start competing.

14-day free trial. Beta rate locked for life. No card required to start.

Start free trial →Try the free carb calculator