A new study by Inoue et al., published in the journal “JAMA Network Open”, reported that walking 8000 steps or more for 1 or 2 days a week was associated with significant reduction in the risk of all-cause mortality and cardiovascular (CV) mortality compared to those who did not walk 8000 steps or more any day of the week. The risk of death decreased further with increasing number of days of walking 8000 steps in the week and plateaued (i.e., showed little/no change) when walking sufficient daily steps for 3–4 days per week. The benefits of walking 8000 steps for 1–2 days in a week were remarkable even when compared with individuals who were more physically active (i.e., walked 8000 steps or more for 3─7 days per week).
This cohort study collected data of adult participants (n = 3,101; ≥20 years of age) from the National Health and Nutrition Examination Surveys 2005–2006, with linkage to the National Death Index until 2019, to assess the dose-response association of the number of days of walking sufficient steps (≥8000) per week with the mortality risk. The participants wore an accelerometer for 1 week and their daily step counts were collected. The participants were categorized into 3 groups according to the number of days per week they did ≥8000 steps, viz., 0 days (n = 632), 1–2 days (n = 532), and 3–7 days (n = 1,937). The follow-up duration of the study was 10 years.
Data were analyzed between April 1, 2022, and January 31, 2023. Adjusted risk differences (aRDs) and 95% confidence intervals (CI) for all-cause and CV mortality after 10 years were estimated using multivariable ordinary least squares regression models, adjusting for potential confounders. The primary model was adjusted for age, sex, race, and ethnicity, insurance status, marital status, smoking, body mass index, estimated glomerular filtration rate, statin use, history of diabetes, hypertension, cardiovascular disease, cancer, and emphysema, and average daily step counts. The results from the primary model are summarized below:
- All-cause deaths were reported in 14.2% of the participants and CV deaths in 5.3% of the participants over the 10-year follow-up period.
- All-cause mortality risk was 14.9% lower among participants who walked ≥8000 steps 1–2 days per week and 16.5% lower among those who walked ≥8000 steps 3–7 days per week compared to those who took ≥8000 steps 0 days per week (Graphic A).
- Similarly, CV mortality risk over 10 years was 8.1% lower among participants who took ≥8000 steps 1–2 days per week and 8.4% lower among those took ≥8000 steps 3–7 days per week compared to those who took ≥8000 steps 0 days per week (Graphic A).
- The 10-year mortality risk declined rapidly with increasing number of days per week of walking ≥8000 steps and plateaued (state of little/no change) at 3–4 days. Similar findings were reported for different thresholds of number of daily steps between 6,000 and 10,000.
- Younger and older participants as well as men and women reported lower 10-year all-cause mortality risk with ≥8000 steps 1–2 days or 3–7 days per week compared to those who walked ≥8000 steps 0 days per week (Graphic B).
Clinical implications
- This is the first study to highlight the benefits of walking 8000 or more steps just a couple of days per week, on the mortality risk.
- The results suggest that individuals who face difficulties in exercising regularly due to work schedule, family commitments, and other reasons may receive significant health benefits by just walking the recommended daily steps for only a couple days a week.
- The study used objective data on daily steps based on accelerometer reading over the 10-year follow-up period, which helped to avoid potential bias from a self-reported data.
- The findings of this study added to the knowledge base from previous studies reporting association of frequency of physical activity with long-term health outcomes.
(Source: Inoue K, Tsugawa Y, Mayeda ER, Ritz B. Association of daily step patterns with mortality in US adults. JAMA Netw Open. 2023;6(3):e235174. Doi: 10.1001/jamanetworkopen.2023.5174)