Can you regain lost muscle mass in later life?
Yes, regaining lost muscle mass in later life is possible, but the earlier you start, the better the outcome. Resistance training is the cornerstone; adequate protein intake (approximately 1.2-1.6 g/kg/day) makes the effect somewhat greater.
Regaining lost muscle mass in later life is possible, but it depends heavily on how far the muscle loss has already progressed. Among people with early-stage muscle loss, nearly one in four returned spontaneously to normal within a year. With advanced muscle loss, full recovery was achieved in only one in sixty, although just over one in eight improved to a less severe stage. Acting early therefore makes a big difference.
Resistance training is by far the most proven approach. It stimulates the building of muscle proteins and remains effective even after periods of enforced rest due to illness or hospitalisation. Older adults do recover more slowly than younger people, partly because muscle responds less well to nutrition and training as you age. This means that extra inactivity, such as bed rest during illness, quickly leads to losses that you then have to fight hard to regain.
Eating enough protein reinforces the effect of resistance training, albeit modestly. For people aged 65 and over, 1.2 to 1.6 grams of protein per kilogram of body weight per day already appears sufficient to see a small but measurable additional effect on muscle mass and leg strength. Protein without resistance training offers no meaningful benefit; the combination is essential.
Creatine (3 to 5 grams per day) can slightly enhance the effect of resistance training in older adults, presumably because it supports higher training intensity and faster recovery. On its own, without training, it does little. Worth noting: several researchers behind the creatine studies have financial ties to creatine manufacturers, so treat those conclusions with some caution. L-carnitine shows preliminary signals, but the evidence is thin and the only review on the topic was funded by a manufacturer of the product.
Nicotinamide (a form of vitamin B3) and pyridoxine (vitamin B6) together appear in animal and laboratory research to activate muscle stem cells and accelerate recovery. Whether this also works in humans has not yet been demonstrated. This is not, for now, a reason to start supplementing.
Evidence for resistance training is strong and causal. Evidence for protein intake is moderate (meta-analysis). Evidence for creatine is moderate but carries a conflict-of-interest caveat. Evidence for L-carnitine is limited and also involves industry funding. Evidence for nicotinamide and pyridoxine is confined to animal and laboratory research.