Aging strong: an N = 1 mixed-methods study of long-term supervised high-intensity resistance training in a...

Older adults who engage in long-term, supervised high-intensity resistance training (HIRT) may preserve musculoskeletal function, independence, and psychological resources beyond typical age-related expectations. This N = 1 mixed-methods study characterized an upper-bound example of "aging strong" in a 71-year-old woman after eight consecutive years of structured HIRT. The participant completed three 60-min HIRT sessions per week emphasizing multi-joint lifts performed close to muscular failure, alongside high daily ambulatory activity and a protein-rich diet. A convergent assessment battery integrated dual-energy X-ray absorptiometry (DXA), one-repetition maximum tests, load-velocity and load-power profiling, functional performance tests (Short Physical Performance Battery, Timed Up and Go, 30-s chair stand, push-ups to failure), validated questionnaires of general self-efficacy and self-esteem, and a semi-structured interview analyzed using reflexive thematic analysis. DXA showed low whole-body fat (15.1%) and a high appendicular lean mass index (10.33 kg·m^-2), exceeding age-matched reference values and sarcopenia thresholds. Maximal strength was exceptional (bench- and leg-press one-repetition maximum of 1.05× and 3.85× body weight, respectively), and functional performance indicated minimal disability risk (Short Physical Performance Battery 12/12, Timed Up and Go 6.08 s, 30-s chair stand 21 repetitions). Load-velocity profiling revealed unusually slow minimal-velocity thresholds, causing standard group-based equations to underestimate measured one-repetition maximum by 11-28%, while load-power curves demonstrated high peak power at approximately 57% of one-repetition maximum in both exercises. Psychological assessments indicated high self-efficacy (35/40) and self-esteem (34/40), and qualitative themes highlighted strength as a foundation for resilience, emotional regulation, unwavering adherence, empowered body image, and training as a central life identity. Together, these integrated findings suggest that long-term, supervised HIRT may support a virtuous cycle in later life in which exceptional strength, power, favorable body composition, and functional independence are tightly linked with robust psychological resources and sustained adherence.