10x Better Muscle synthesis* Build Lean Muscle
Clinically Studied Backed by Clinical Research
Advanced Amino Formula Advanced Amino Formula
Speeds Recovery Time Third Party Tested
Athlete Approved Enhances Endurance

Same Formula: Capsules or Powder

NASA-FUNDED PATENTED FORMULA

Faster Recovery

Faster Recovery

Our patented formula helps you recover faster, and reduce soreness after workouts.

Cellular Energy

Cellular Energy

Supports natural energy production at the cellular level, helping fuel consistent, high-quality training sessions.

Maintain Muscle

Maintain Muscle

Help Prevent Muscle Loss as you age.

Muscle Code Advanced Aminos
Patented Amino Formula

Patented Amino Formula

Builds & Maintains Muscle 10x better than whey protein Isolate.

Rapid Absorption

Rapid Absorption

Our advanced amino formula starts to work in less than 20 minutes.

Endurance Support

Endurance Support

EAAs help delay fatigue and sustain energy during intense workouts, keeping your muscles performing longer.

How it Works

Our advanced amino formula starts to work in less than 20 minutes — for faster, more efficient muscle building.

  • Build Strength — Stimulates rapid muscle protein synthesis
  • Boost Endurance — Enhances amino acid delivery to working muscle
  • Recover Fast — Rebuilds muscle quickly with high-efficiency EAAs
  • Support Health — Helps maintain lean mass and physical function

Customers Love MUSCLE CODE

Woman with curly hair wearing a red top and white cardigan indoors

I love it!

“I feel better than ever. And my secret is Muscle Code.”

- Rio

Verified Purchase
rio muscle code

Absolutely the best!

“Now I'm building muscle fast, getting stronger, and looking younger.”

- Victoria

Verified Purchase
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I feel great!

“Muscle Code helps me look and feel younger.”

- Phil

Verified Purchase

Trusted by the best

Backed by Our Advisory Board

Dr. Smith Johnston

Dr. Smith Johnston, MD, MS, is a leading expert in space medicine with more than 25 years as a NASA Flight Surgeon, where he cared for astronauts, operationally supported over 25 Space Shuttle and 2 International Space Station (ISS) missions. 

As Johnson Space Centers Aerospace and Occupational Clinic Medical Director from 2015 to 2019, he oversaw astronaut medical standards, fatigue management, and human performance programs. He retired NASA in 2019 and became the first Chief Medical Officer at Axiom Space, guiding crew health and readiness for private astronaut missions. In 2023 he left that position and now consults for numerous advanced medical technology and preventive medicine companies, and is a professor of Aerospace Medicine at The University of Central Florida, Aerospace Department of Medicine.

"I believe the Muscle Code formula shows great promise for augmenting and extending human performance and longevity, and especially in our aging populations. It’s what I use and what also recommend to my active and retired Astronauts and my earth bound patients."

Aerospace Medicine Specialist

Dr. Robert Wolfe

Dr. Robert Wolfe, PhD, a leading researcher in muscle metabolism, has spent decades uncovering the power of amino acids in human health. With a career rooted in clinical research and physiology, he became particularly intrigued by how the body repairs and builds muscle—especially in aging populations and athletes.

His research led to a groundbreaking discovery: essential amino acids (EAAs) play a far more critical role than previously thought. Unlike complete proteins, EAAs could stimulate muscle protein synthesis rapidly, even without exercise. This had profound implications—not just for body builders, but for older adults losing muscle mass, patients recovering from surgery, and anyone looking to improve recovery and performance.

"As both the inventor and a committed daily user of Muscle Code, I rely on it to keep my energy strong and my muscles performing at their best. The amino acids in Muscle Code help me stay energized, support my muscle strength, and recover smoothly so I can keep moving without slowing down. It’s the formula I trust—because I created it to truly work."

The Amino Acid Pioneer

Science Backed Ingredients

Key Ingredients

EAAlpha® Reginator Essential Amino Acids Capsule (3600 mg)

  • L-Leucine
  • L-Lysine HCl
  • L-Valine
  • L-Isoleucine
  • L-Arginine
  • L-Threonine
  • L-Phenylalanine
  • L-Methionine
  • L-Histidine
  • L-Tryptophan
  • Vegetable Capsule
  • Vegetable Magnesium Stereate
  • Silicon Dioxide

Frequently Asked Questions

What is Muscle Code?

Muscle Code by Nautilus is a patented, clinically proven essential amino acid (EAA) supplement formulated in the precise ratio your body needs to maximize protein synthesis.

What makes Muscle Code different from other protein or amino acid supplements?

Unlike generic amino blends or incomplete proteins, Muscle Code contains EAAs in the exact balance required for effective muscle protein synthesis. This ensures nothing is wasted, giving you better results with less effort.

How does Muscle Code work to build muscle and aid recovery?

Leucine triggers muscle protein synthesis, while the other EAAs provide the raw material for new muscle tissue. Together, they repair muscle damage and accelerate recovery.

Who should take Muscle Code?

· Athletes & fitness enthusiasts to maximize training gains

· Aging adults to maintain lean muscle and strength

· Post-surgery or illness recovery to prevent muscle loss

· Anyone looking to support muscle health, recovery, or total-body protein needs

What is the recommended amount to take?

Take 4 capsules once a day.