This study evaluates the effects of a 12-week leucine-enriched protein supplementation in adults aged 60 years and more. Participants will undergo assessments of muscle mass and function, as well as metabolic profiles in blood, urine, and feces before and after the intervention.

Inclusion Criteria:

1. Willing to provide written informed consent.
2. Participants who attend health check-ups at Songshan District, Taipei City, or at the Wellness Cultural Village, or who have participated in the pilot study.
3. Adults aged 60 years or older, male or female.
4. Able to ambulate independently.
5. Meets at least one of the following sarcopenia criteria:

Grip strength: Men < 28 kg; Women < 18 kg Gait speed: < 1.0 m/s Muscle mass (appendicular skeletal muscle mass / height²): Men < 7.0 kg/m²; Women < 5.7 kg/m²

Exclusion Criteria:

1. Impaired renal function.
2. Allergy or intolerance to protein supplements.
3. Currently undergoing cancer treatment.
4. Autoimmune diseases.
5. Assessed by a physician as unsuitable to participate.

Due to ethical and privacy considerations, individual participant data will not be publicly available. De-identified data may be shared upon reasonable request and with approval from the institutional review board.