Supplement analysis backed by scientific evidence · PT

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Limited evidencePhysical performance

HICA (Alpha-Hydroxyisocaproic Acid)

A minor leucine metabolite sold for lean mass and reduced soreness. One small positive trial in soccer players was not confirmed by later, better-controlled resistance-training studies.

Evidence last reviewed: August 2026

What the science says

  • Lean mass in trained athletes Limited evidence

    A single 4-week randomized trial in 15 soccer players reported about 0.4 kg more lean mass with 1.5 g/day of HICA than placebo. The sample was very small and the finding has not been replicated.

  • No effect with resistance training Limited evidence

    A 10-week randomized trial in resistance-trained men found no effect of HICA (or HMB) on body composition, and a companion report found no effect on strength or muscle thickness. These are the largest and best-controlled data available, and they are negative.

  • Muscle soreness Limited evidence

    Reduced delayed-onset muscle soreness was a secondary outcome in the same small soccer trial, with no independent confirmation. Treat it as a hypothesis rather than a result.

Dosage & safety

Studied doseTrials used 1.5 g/day, split into three 500 mg doses with meals, for 4–10 weeks.
SafetyWell tolerated in trials lasting up to 10 weeks, with no notable adverse effects reported. There are no long-term safety data, and no data in adolescents, pregnancy or breastfeeding.

Scientific references

Where to buy

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