Protein for Muscle Preservation
More protein, distributed across meals
The 0.8 g/kg/day RDA is the bare minimum to prevent protein deficiency — not the optimal for muscle preservation. Active adults benefit from 1.4–1.6 g/kg, and adults over 50 from 1.6–2.0 g/kg. Distribution matters too: spreading 30–40 g across 3–4 meals beats slamming most at dinner.
Leucine threshold per meal
Muscle protein synthesis is triggered by leucine — an essential amino acid. Younger adults trigger synthesis at ~2 g leucine per meal (~20 g complete protein). Older adults have a higher threshold, requiring ~3 g leucine (~30–40 g protein). Plant proteins are lower in leucine; mixing or supplementing matters more for older plant-eaters.
Quality + timing — practical version
Three meals × 30–40 g complete protein, plus a 20–30 g shake post-training, hits 110–150 g/day for a 70 kg adult. Animal-source proteins (whey, eggs, lean meat, fish, dairy) are highest-quality. Plant-eaters: combine sources (legume + grain) and lean toward soy + pea isolates which are leucine-richer.
The pre-sleep casein window
Sleep is a 7–9 hour fast — and during it, muscle protein breakdown ticks up. 30–40 g of slow-digesting protein (casein, cottage cheese, Greek yogurt) 30 minutes before bed releases amino acids steadily across the night, suppressing breakdown and keeping overnight muscle protein synthesis elevated. Trommelen + van Loon (2016) showed pre-sleep casein increases overnight MPS roughly 22 % — meaningful for older adults already fighting anabolic resistance.
Plan a protein-distributed day
Drag each meal to its target protein dose for a 70 kg adult over 50.
Key Takeaway
Protein matters more, not less, with age. Target 1.6–2.0 g/kg/day spread across 3–4 meals of 30–40 g each. Leucine drives muscle protein synthesis; older adults have a higher threshold per meal. Add 30–40 g pre-sleep casein for an extra overnight MPS bump. Pair this with the resistance training protocol and sarcopenia largely doesn't happen.