If you are reading this article sitting down, get up and start moving. The results of a new study lends further proof that the greater your daily step counts (steps/day) the lower your risk for all-cause mortality. However, no significant association was identified between the intensity of steps (steps/min, or cadence) and all-cause mortality, according to results of the study published in JAMA.
Researchers identified a representative sample of US adults aged ≥40 years from the National Health and Nutrition Examination Survey (NHANES). From 2003 to 2006, participants were asked to wear an accelerometer on their hip during waking hours for a 7-day period. A total of 4840 individuals with at least 1 day of valid accelerometer use were included in the study; of these individuals, 2435 (54%) were women and 1732 (36%) were obese.
Participants’ height and weight were obtained and diet quality was assessed with the Healthy Eating index. Total steps per day were computed by summing daily steps and calculating median values from the valid days for each participant. Step intensity or cadence was estimated using 3 metrics: extended bout cadence (consecutive minutes), peak 30 minute cadence, and peak 1-minute cadence. The primary outcome was all-cause mortality, recorded as of December 2015; secondary outcomes included underlying outcomes of death caused by cardiovascular disease (CVD) and cancer.
The accelerometer was worn for a mean of 5.7 days for a mean of 14.4 hours per day; 94% of participants wore the monitor for at least 10 hours a day for at least 3 days. Participants took a mean of 9124 steps per day. During the follow-up period, 1165 participants died including 406 patients with CVD and 283 patients with cancer.
The unadjusted incidence density for all-cause mortality was 76.7 per 1000 person-years (419 deaths) for the 655 individuals who took <4000 steps per day, 21.4 per 1000 person-years (488 deaths) for the 1727 individuals who took 4000 to 7999 steps per day, 6.9 per 1000 person-years (176 deaths) for the 1539 individuals who took 8000 to 11,999 steps per day, and 4.8 per 1000 person-years (82 deaths) for the 919 participants who took at least 12,000 steps per day.
Unadjusted incidence density for all-cause mortality by peak 30 minute cadence was 32.9 per 1000 person-years (406 deaths) for the 1080 participants who took 18.5 steps/min, 12.6 per 1000 person-years (207 deaths) for the 1153 individuals who took 56.1 to 69.2 steps/min, 6.8 per 1000 person-years (124 deaths) for the 1074 individuals who took 69.3 to 82.8 steps/min, and 5.3 per 1000 person-years (108 deaths) for the 1037 individuals who took 82.9 to 149.5 steps/min. After adjustment for total steps per day, greater step intensity was not significantly associated with lower mortality.
The researchers noted that participants who took more steps were significantly younger, had lower body mass index (BMI) scores, lower diet quality, a higher education level, a higher proportion of current drinkers but a lower prevalence of comorbid conditions and mobility limitations.
“Future studies of walking intensity and mortality using more sophisticated measures of cadence could help confirm these findings and explain possible differences in mortality rates when using measures of cadence, gait speed, and self-reported walking speed.”
Saint-Maurice PF, Troiano RP, Bassett DR Jr, et al. Association of daily step count and step intensity with mortality among US adults. JAMA. 2020;323(12):1151-1160.