Moderate evidencePhysical performance

Free-Form Amino Acid Complex

Pre-digested amino acids covering the full spectrum. The useful evidence is in older adults and undernourished patients; for healthy people already eating enough protein there is little to gain over food.

Evidence last reviewed: August 2026

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What the science says

Strength and physical function in sarcopenia Moderate evidence
A 2026 systematic review and meta-analysis of nine RCTs (496 participants with sarcopenia) found amino acid supplementation plus resistance training improved grip strength, gait speed and physical performance versus training alone. Certainty was rated low to very low, and effects on muscle mass remained limited.
Older adults with acute or chronic illness Moderate evidence
A systematic review and meta-analysis of protein and amino acid supplements in older adults with acute or chronic conditions found benefits concentrated in undernourished groups rather than in well-nourished ones.
No clear advantage over food protein Limited evidence
An umbrella review of nutritional interventions for muscle in older people found supplements added little when habitual protein intake was already adequate. No trial shows free-form amino acids outperform whole protein in well-fed adults.

Dosage & safety

Studied doseStudied regimens deliver roughly 6–15 g/day of essential amino acids, split around meals or training. Tablet-based label doses often supply considerably less.

SafetyGenerally well tolerated. People with kidney disease, liver disease or a urea-cycle disorder should not take concentrated amino acids without medical advice. Anyone with phenylketonuria must check the phenylalanine content.

Scientific references

Combined resistance training and amino acid-based supplementation for sarcopenia in older adults: a systematic review and meta-analysis
Xie C, Yan R, Tao R — BMC Musculoskelet Disord, 2026
Systematic review and meta-analysis of the effect of protein and amino acid supplements in older adults with acute or chronic conditions
Cheng H, Kong J, Underwood C — Br J Nutr, 2018
Nutritional interventions to improve muscle mass, muscle strength, and physical performance in older people: an umbrella review of systematic reviews and meta-analyses
Gielen E, Beckwée D, Delaere A — Nutr Rev, 2021

Where to buy

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Related in Physical performance

Creatine (monohydrate) Strong evidence
Whey Protein Strong evidence
Caffeine Strong evidence
Beta-Alanine Moderate evidence
BCAA (Branched-Chain Amino Acids) Limited evidence
EAA (Essential Amino Acids) Moderate evidence