Flexible For Stressed Joints

Flexible Creatine Serum is a safe no-loading, no maintenance formula which provides a simple and effective way for athletes to maintain healthy joints while optimizing the body’s muscle-building and fat-burning processes.

It offers advanced joint relief and repair. Flexible includes a 100% bioavailable form of the powerful glucosamine sulfate which influences joint health by providing cartilage with added strength, structure, and resilience while retaining fluidity, elasticity, and flexibility in your bone, ligament, and tendon structures.



Shipping info: Fast Shipping. Arrives in 3-5 business days for orders within US.

This product is for:

Individuals Who Want To Fuel Their Muscle In Minutes

Energizes Tired Muscles And Soothes Joint Pain



Flexible Serum is absorbed quickly and efficiently. Taken with a dropper in small doses under the tongue, the serum is quickly absorbed by the mucous membranes in the mouth, bypassing the stomach and digestive system and thereby retaining a much higher potency. In contrast, other forms of creatine can take up to an hour to digest in addition to a loading period of five days and daily maintenance.

Each serving is assimilated into the bloodstream within minutes. As a result, there is no time for the waste products, and creatinine to develop.

Due to its easy dosages and water solubility, Creatine Serum doesn’t cause dehydration and muscle cramping because no loading or maintenance is required. Taken only on the days you work out it works quickly and effectively and causes no side effects, no matter how much you take.


Guided by the respect for science, a devotion to natural ingredients, a love of life, and a commitment to staying real- we create products that embody truth- products as Flexible Serum. Naturally formulated with powerful amino acids, herbs, and nutrients; serious athletes Flexible increases ATP production and delays lactic acid build-up, increasing energy and stamina on-demand. And because it’s manufactured by Muscle Marketing USA, you can be sure the convenient serum delivery system is safe and effective. What we love about is what you’ve come about to love us. It’s all in the drive for what we do, and that is as real as real gets.



Muscle is our first name. But our family name is USA. All our products are sourced and manufactured in the United States. We comply with all good manufacturing practices.

SINCE 1995

We have been committed to empowering athletes all over the world. Since our invention of Creatine Serum over 25 years ago, we have changed the way the world works out. By offering everyone who wants to try, the power to be their best.

How to use

One 5ml serving of creatine serum supplies the equivalent of 2,500 mg of creatine monohydrate. Before activity use the dropper to place 5 (1ml) portions under the tongue. Hold serum under the tongue for best absorption. May also be swallowed or mixed with water or juice.


Vitamin B12
Vital For Aerobic Performance and Healthy Red Blood Cells


Radical Muscle Building Compound Supercharges Strength

Fast Metabolizing Disaccharide for Rapid High-Energy

Glucosamine Sulfate
For Structural Integrity of Joints, Connective Tissues, and Blood Vessels

Eleutherococcus Senticosus
Anti-Inflammatory Adaptogen Increases Endurance

Key Benefits

  • Promotes Quick Lean Muscle Gain
  • Delays Lactic Acids Build-Up
  • Supports Intense Cardio Training
  • Protects Joints
  • Promotes Recovery