Why older muscles don't build as well after protein and exercise
Inositol hexakisphosphate kinase 1 is implicated in the insulin response to protein ingestion in older adults
Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
After eating protein and lifting weights, young muscles use amino acids better because a molecule called IP6K1 drops, helping build muscle. Older muscles don't drop IP6K1 as much, so even with more insulin, they don't use amino acids well.
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Not medical advice. For informational purposes only. Always consult a healthcare professional. Terms
After eating protein and lifting weights, young muscles use amino acids better because a molecule called IP6K1 drops, helping build muscle. Older muscles don't drop IP6K1 as much, so even with more insulin, they don't use amino acids well.
Systematic Reviews & Meta-Analyses
Max 100Randomized Controlled Trials
Max 90Cohort Studies
Max 72Case-Control Studies
Max 58Cross-Sectional Studies
Max 44Case Reports & Case Series
Max 30Expert Opinion & Narrative Reviews
Max 546 / 90
Evidence Score
Participants are randomly assigned to treatment or control groups, minimizing bias. Considered the gold standard for testing whether an intervention causes an effect.
Publication
Authors
Barclay RD, Motei DE, Ancu O, Tyler CJ, Tillin NA, Behrends V, Burd NA, Hurren NM, Mackenzie RWA
Related Content
Claims (3)
In older adults with insulin resistance, levels of a specific protein called IP6K1 in the blood and muscles are lower after consuming whey protein, compared to younger adults. These lower levels are linked to a reduced ability to process amino acids from the protein, which may help explain why aging affects how the body uses amino acids and responds to insulin.
In older adults with insulin resistance, consuming protein and doing resistance exercise causes a larger spike in insulin than in younger adults, but this higher insulin level does not lead to better use of amino acids or increased muscle-building signals.
After consuming 25 grams of whey protein, young adults experience a reduction in a specific muscle protein called IP6K1, which coincides with increased processing of the amino acid phenylalanine and activation of a protein involved in muscle growth, indicating a possible role for IP6K1 in regulating muscle anabolic responses.