Resumen: Purpose: Purpose to evaluate the prevalence and temporal trends in adherence to muscle-strengthening activity (MSA) guidelines among the US population from 1997 to 2018 (pre-Covid 19). Methods: We used nationally representative data from the National Health Interview Survey of the US (NHIS; a cross-sectional household interview survey). We pooled data from 22 consecutive cycles (1997 to 2018) and estimated prevalence and trends of adherence to MSA guidelines among adults aged 18–24 years, 25–34 years, 35–44 years, 45–64 years, and ≥ 65 years. Results: A total of 651,682 participants (mean age 47.7 years [SD = 18.0], 55.8% women) were included. The overall prevalence of adherence to MSA guidelines significantly increased (p < .001) from 1997 to 2018 (19.8% to 27.2%, respectively). Adherence levels significantly increased (p < .001) for all age groups from 1997 to 2018. Compared with their white non-Hispanic counterparts, the odds ratio for Hispanic females was 0.5 (95% CI = 0.4–0.6). Conclusions: It is over a 20-year span, adherence to MSA guidelines increased across all age groups, although the overall prevalence remained below 30%. Future intervention strategies to promote MSA are required with a particular focus on older adults, women, Hispanic women, current smokers, those with low educational levels, and those with functional limitations or chronic conditions. Idioma: Inglés DOI: 10.1016/j.genhosppsych.2023.06.016 Año: 2023 Publicado en: GENERAL HOSPITAL PSYCHIATRY 84 (2023), 89-95 ISSN: 0163-8343 Factor impacto JCR: 4.1 (2023) Categ. JCR: PSYCHIATRY rank: 52 / 279 = 0.186 (2023) - Q1 - T1 Categ. JCR: PSYCHIATRY rank: 52 / 279 = 0.186 (2023) - Q1 - T1 Factor impacto CITESCORE: 9.6 - Psychiatry and Mental Health (Q1)