Self-perceived muscular strength, physical activity, and Mediterranean Diet: Impact on health-related quality of life in older adults

Summary: The global rise in life expectancy poses challenges for individuals in maintaining independence, health, and quality of life. Health-related quality of life (HRQoL), a key indicator encompassing physical and mental well-being, is crucial for population health monitoring. Regular physical activity (PA), especially muscle-strengthening routines and adherence to the Mediterranean Diet (MD), positively influence HRQoL. Understanding the link between muscular strength and HRQoL is essential for effective physical activity interventions. This study explores the association between self-perceived muscular strength (MS), HRQoL, MD, and sports habits in older adults.The study followed a cross-sectional, descriptive and comparative design, with a sample of 433 physically active Spanish subjects aged 41 to 80. Stratified by MS levels, the high-level group (n = 210; 74.76% men; 57.00 years old (SD: 8.28), and the low level (n = 223; 51.50%; 71.30% men; 55.64 years (SD: 8.56). Self-reported data on MS, HRQoL, MD and PA were collected using the Physical Self-Perception Profile (PSPP 30), Health-Related Quality of Life (SF-36), Mediterranean Diet Adherence Screener (MEDAS) and Rapid Assessment of Physical Activity Questionnaire (RAPA-Q) questionnaires, respectively. An ad-hoc questionnaire captured sports habits and sociodemographic data.The higher MS group exhibited superior physical function (P = 0.002, d = 0.16), physical role (P = 0.023, d = 0.22), general health (P < 0.001, d = 0.61), vitality (P < 0.001, d = 0.52), and mental health (P < 0.001, d = 0.29), along with stronger adherence to the Mediterranean Diet (P < 0.001, d = 0.31). Logistic regression models indicated that a high MS level is associated with engagement in maintenance sports (ORcr = 1.71, 95% CI 1.17–2.50, P = 0.005), practicing 3 or more sports (ORadj = 1.78, 95% CI 0.95–3.36, P = 0.028), leading a very active lifestyle (ORadj = 1.96, 95% CI 1.32–2.94, P < 0.001), and adherence to MD (ORadj = 1.64, 95% CI 1.10–2.45, P < 0.016).Engaging in diverse sports, giving priority to maintenance activities and including daily muscle-strengthening routines beyond WHO guidelines, correlates with higher self-perceived strength in older adults. This, in turn, aligns with an elevated quality of life encompassing both physical and mental health, as well as increased adherence to the Mediterranean Diet. Consideration of these factors is crucial when prescribing physical activity for this population and designing institutional health programs.