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THE Performance Myostatin Inhibitor.

FST-550™ is a specialized oral formula comprised of epicatechin (150mg/capsule), 5A-hydroxy laxogenin (50mg/capsule), and beta-hydroxy beta-methylbutyrate (300mg/capsule).

It is designed for the exclusive purpose of increasing muscle growth in performance animals.

FST-550™ is only available from Thymosin Labs™.

The Science

FST-550™ is scientifically engineered to inhibit the action of myostatin, a protein responsible for preventing muscular growth and development. It also activates the anabolic P13K/Akt signaling pathway, promoting increased protein synthesis and decreased muscle degradation.

This results in a powerfully synergistic effect that supercharges the growth and repair of muscle tissue, driving lean mass beyond normal physiological limits.

Benefits of FST-550™
  • Powerful myostatin inhibition
  • Supraphysiological muscle gain
  • Increased strength
  • Improved exercise capacity
  • Enhanced muscle tissue repair
  • Increased protein synthesis
  • Reduced muscle tissue breakdown (anti-catabolic)
  • Epicatechin; 5A-Hydroxy Laxogenin; Beta-hydroxy beta-methylbutyrate
Dosage: 1-3 capsules daily.
  • - Under 65 lbs.: 1 capsule daily
  • - 65 lbs. to 140 lbs.: 1 to 2 capsules daily
  • - 140 lbs. to 300 lbs.: 2 to 3 capsules daily
  • - 300 lbs. to 600 lbs.: 3 capsules daily
  • - Over 600 lbs.: 3+ capsules daily
  • Only give FST-550™ to your animal as directed by a veterinary professional.

Example Dosage Cycles

How it Works

FST-550™ works by reducing the muscle-limiting effects of myostatin in your animal’s body. It does this by stimulating increased levels of follistatin, a protein that inhibits the action of myostatin by binding to it.

With less myostatin able to inhibit muscle tissue growth, lean mass is free to develop beyond normal physiological barriers.

At the same time, FST-550™ activates Akt, a critical intermediary in the IGF-1signaling pathway which plays a central role in stimulating skeletal muscle growth.

With increased Akt activity, muscle development is enhanced while protein breakdown is reduced, further driving lean mass gain to considerable new heights.

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