Efficacy of leucine-rich high protein supplementation on body composition and muscle function among older adults with sarcopenia: a randomized controlled trial.

Leucine-rich high protein supplementation produced no significant intervention effect on body composition as measured by anthropometry and bioelectrical impedance analysis.

• Repeated measures ANOVA showed no significant intervention effect in body composition measurements including anthropometry and BIA
• Study duration was 12 weeks with measurements at 0, 6, and 12 weeks
• 47 participants were recruited, predominantly women (89.4%) with mean age of 69.3 ± 7.1 years
• Intervention group consumed 2 sachets of high protein supplement daily providing 50.6 g of protein/day and 6 g of leucine/day

Leucine-rich high protein supplementation produced no significant intervention effect on muscle function as measured by the Short Physical Performance Battery (SPPB).

• Repeated measures ANOVA showed no significant intervention effect in SPPB score
• Measurements were performed at 0, 6, and 12 weeks
• Participants were older adults with or at risk of sarcopenia residing in Klang Valley, Malaysia
• The trial was double-blinded and randomized with a control group receiving placebo supplement

Genes responsible for ATP production, cell proliferation, and DNA repair were significantly up-regulated in the intervention group.

• Genes GBA and MLYCD, responsible for adenosine triphosphate (ATP) production, were significantly up-regulated in the intervention group (p < 0.05)
• STAT5A, responsible for cell proliferation, was significantly up-regulated in the intervention group (p < 0.05)
• BRCC3, responsible for DNA repair, was significantly up-regulated in the intervention group (p < 0.05)
• Gene expression was determined by mitochondrial RNA activity derived from peripheral blood mononuclear cells
• A total of 16 ml of full blood was collected pre- and post-study to assess changes in gene expression

The study population was predominantly female older adults with sarcopenia or at risk of sarcopenia.

• 89.4% of participants were women
• Mean age of participants was 69.3 ± 7.1 years
• 47 participants total were recruited from Klang Valley, Malaysia
• Participants had sarcopenia or were at risk of sarcopenia

The authors concluded that longer supplementation periods and larger sample sizes may be needed to detect noticeable changes in body composition.

• The trial duration was 12 weeks
• Sample size was 47 participants
• Authors stated 'further studies with a longer supplementation period and a larger sample size might be needed for noticeable changes, particularly for body composition'
• Body composition was assessed via anthropometry, BIA, and MRI of left mid-thigh