Builds Lean Muscle Builds Lean Muscle
Improves Strength & Power Improves Strength & Power
Enhances Endurance Enhances Endurance
Speeds Recovery Time Speeds Recovery Time
Backed by Clinical Research Backed by Clinical Research
1 7

Advanced Aminos

Muscle Code Amino Capsules

Muscle Code Amino Capsules

  • Up to 10X greater muscle synthesis than whey protein isolate, gram for gram
  • Patented EAA Formula – All 9 essential amino acids to support muscle protein synthesis and recovery
  • Rapid Absorption – Quickly absorbed to support strength and post-workout recovery
  • Clean & Dairy Free – vegan, non-GMO, gluten-free, lactose-free
  • NASA & NIH Funded Research – Developed by Dr. Robert Wolfe, a world leader in amino acid science.
  • Made in USA with globally sourced ingredients & Third-Party Tested – Manufactured in a GMP-certified and NSF certified facility for quality assurance.
  • Convenient & Mess friendly – 4 per serving. No chalky powders or cleanup
$44.99 USD
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$74.99 USD
$67.49 USD

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One or more items in your cart is a subscription. By continuing with your payment, you agree that any subscription will automatically renew at the price and frequency listed on this page until it ends or you cancel.

One or more items in your cart is a subscription. By continuing with your payment, you agree that any subscription will automatically renew at the price and frequency listed on this page until it ends or you cancel. All cancellations are subject to the cancellation policy.Nautilus provides an autoship subscription service. By subscribing to our service, you have confirmed that you accept our Terms of Service. Your membership will automatically renew on a recurring basis at which time your credit card will be charged automatically for the subscription products, including applicable shipping and handling fees until you cancel your membership.You may make modifications to your membership or cancel at anytime by logging in to your account, selecting Subscriptions, then clicking cancel next to the item. Cancellation requests submitted via email must be sent at least 24 hours prior to the subscription renewal date.

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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

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I love it!

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

- Rio

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rio muscle code

Absolutely the best!

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

- Victoria

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I feel great!

“Muscle Code helps me look and feel younger.”

- Phil

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The Science of Muscle Code & How it’s Made

What you can find in Muscle Code

  • Clinically Proven Amino Acids
  • Vegan & Clean Formula
  • Zero Sugar & No Artificial Flavors
  • Researched & Developed Backed by amino acid science
  • Made in a GMP-Certified Facility
  • Gluten Free, Dairy Free, Soy Free, Nut Free, Shellfish Free

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.

"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, 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

Frequently Asked Questions

About Muscle Code Usage & Dosage Absorption & Effectiveness Ingredients Safety

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.

What are the active ingredients in Muscle Code?

A proprietary blend of all nine essential amino acids (including leucine, isoleucine, valine, lysine, methionine, phenylalanine, threonine, histidine, and tryptophan) plus arginine in the correct clinical ratio.

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

How do I take Muscle Code?

Take 4 capsules once a day.

What is the recommended dosage?

One serving daily, or as directed by your health professional.

When is the best time to take Muscle Code?

Best taken after workouts to maximize recovery, but it can also be used in the morning, between meals, or before bed to support ongoing protein synthesis.

Can I take it on an empty stomach?

Yes. Muscle Code is light, fast-absorbing, and won’t cause bloating.

Can Muscle Code be taken daily, even on rest days?

Yes, daily use ensures consistent support for recovery and muscle preservation.

Yes, daily use ensures consistent support for recovery and muscle preservation.

Many users feel improved recovery within 1–2 weeks, with muscle and strength benefits in 4–6 weeks.

Should I take Muscle Code if I already use a pre-workout?

Yes. Pre-workouts provide energy and focus, while Muscle Code provides the building blocks for muscle repair. Use post-workout if you’re already taking a pre-workout.

What is the shelf life?

Typically 2 years when stored properly (see label for exact date).

How should I store Muscle Code?

At room temperature, in a cool, dry place. Refrigeration is not required.

What does Muscle Code taste like?

The capsules are tasteless, odorless, and easy to swallow.

How quickly is Muscle Code absorbed?

It is rapidly absorbed—typically within 30 minutes—faster than most whole protein sources.

How does it compare to whey protein?

Whey provides protein but not always in the right ratio of EAAs. Muscle Code is more efficient, requiring less volume for superior muscle protein synthesis.

Will it help without exercise?

Yes, Muscle Code supports protein synthesis even at rest, helping maintain muscle during illness, aging, or recovery.

Can it aid recovery after surgery, illness, or injury?

Yes. By preventing muscle breakdown, it supports faster rehabilitation and whole-body repair.

Is Muscle Code vegan?

Yes.

Is it free of allergens?

Yes—no gluten, dairy, soy, nuts, or shellfish. Always check label for latest allergen info.

Does it contain fillers, binders, or artificial sweeteners?

No. Muscle Code is free from unnecessary fillers and artificial additives.

What certifications does it have?

Manufactured in a cGMP-certified, NSF-certified, and third-party tested facility for quality and safety.

Where is it manufactured?

Proudly manufactured in the USA under strict quality standards.

Are there any side effects?

Muscle Code is well-tolerated. No common side effects have been reported.

Can I take it with other supplements?

Yes. It can be stacked with protein powders, creatine, or pre-workouts.

Can I take Muscle Code if pregnant or breastfeeding?

Consult your healthcare provider before use.

Is it safe for children or teens?

Muscle Code is designed for adults. Consult a pediatrician before use in minors.