Muscle power declines earlier and faster than strength with age, even in trained lifters, and power training modestly improves function in older adults
Interpretation
The decline is consistent across designs: a cross-sectional study of 1,305 adults found relative leg power falling after 40 in both sexes (Alcazar 2020); master weightlifters and controls aged 40-87 lost power at about 1.2-1.3% a year versus 0.5-0.6% for strength, with lifters 32% more powerful (Pearson 2002); and healthy adults in their 70s lost 8.8% of power over about 3 years while preserving strength (Reid 2014). On training, a meta-analysis of 20 RCTs in 566 adults over 60 found power training improved physical function slightly more than traditional strength training, at low certainty (Balachandran 2022). Graded moderate because the decline evidence is consistent but mostly cross-sectional and in non-triathletes, and the training evidence is low certainty and measures function rather than sport performance.
Practical implication
Triathletes over 50 can keep some heavy lifting and add fast-intent lifting with moderate loads, and low-level jumps if joints, tendons and bones allow, once a strength base is in place. This is extrapolated from older non-athletes, master weightlifters and a small trial in master runners; no trial has tested power training on triathlon performance.
Sources
5 sources, independently verified.
Review concluding that muscle power declines earlier and more steeply with age than strength, that peak power is an important predictor of functional limitation in older adults, and that lower-limb power may be a more discriminating measure than strength. Based on research in older non-athletes.
Cross-sectional Copenhagen Sarcopenia Study data: relative leg power began to decline after age 40 in both women and men, and absolute leg extension power after the fourth decade, with later losses of leg lean mass adding to the decline. General population, not athletes.
Over about 3 years, leg power fell 8.8% in healthy older adults (mean 74) and 8.5% in mobility-limited older adults (P > 0.8). The healthy group preserved muscle size and strength while losing power; the mobility-limited group lost size (-3.8%) and strength (-5.9%). Older non-athletes.
Elite master weightlifters had 32% more peak leg power and 32% more knee-extensor strength than untrained age-matched controls. Peak power declined about 1.2%/year (lifters) and 1.3%/year (controls), roughly twice the rate of isometric strength (0.6% and 0.5%/year); an 85-year-old lifter was as powerful as a 65-year-old control. Cross-sectional; select population; sex split not given in the abstract.
Power training improved physical function modestly more than traditional strength training (SMD 0.30, 95% CI 0.05 to 0.54; 13 RCTs, n = 383), with low-certainty evidence; self-reported function did not differ clearly (3 RCTs, n = 85). Older community-dwelling non-athletes; outcomes were functional tests, not sport performance.