Sustained midlife activity halves death risk
Women who met recommended weekly physical activity levels for 15 years had lower overall death risk than women who did not.
*Prospective cohort target trial emulation; Level 2b (OCEBM).
Citation
Nguyen B, Owen KB, Luo M, Brown W, Mielke GI, Clare PJ, Ding D. Physical activity across mid-life and mortality outcomes in Australian women: A target trial emulation using a prospective cohort. PLoS Medicine. 2026;23(3):e1004976. doi:10.1371/journal.pmed.1004976
Background
Many studies link physical activity to longer life, but often measure activity only once. This study used repeated surveys to compare long-term activity patterns and later mortality.
Patients
11,169 Australian women (born 1946–1951) in a national cohort; activity pattern assessed from about ages 50–70. Excluded women with very low physical functioning (lowest 5%) before the exposure period.
Intervention
Consistently meeting World Health Organization activity recommendations (at least 150 minutes/week of moderate-to-vigorous physical activity) for 15 years; also examined starting to meet recommendations at about age 55, 60, or 65.
Control
Consistently not meeting the 150 minutes/week recommendation.
Outcome
Death from any cause (primary), and deaths from cardiovascular disease and selected cancers, from national death registries.
Follow-up Period
15-year activity pattern (2001–2016); deaths tracked to 2019.
Results
| Comparison |
All-cause mortality risk |
Risk ratio (99.5% CI) |
Approximate NNT |
| Consistent adherence vs consistent non-adherence |
5.3% vs 10.4% |
0.50 (0.27 to 0.94) |
20 |
NNT = number needed to treat (here: number needing to meet recommendations for ~15 years to prevent one death), based on the reported absolute risk difference point estimate; uncertainty was substantial.
Results for cardiovascular disease mortality, cancer mortality, and “starting later” patterns were not conclusive.
Limitations
Physical activity was self-reported. Cause-specific deaths were relatively few, limiting certainty. Some confounding may remain. Findings may not apply to women with poor physical functioning or to all Australian women.
Funding
Australian Government Department of Health; national research fellowships. No reported funder role.
Clinical Application
Reinforces advising midlife women to sustain ≥150 minutes/week activity long term; evidence for “starting later” is uncertain. Possible indication creep: results exclude women with very poor function.