What is the association between the number of days taking a sufficient number of steps throughout the week and mortality among US adults?

By Bhavana KunkalikarReviewed by Lily Ramsey, LLMMar 31 2023

In a recent study published in the JAMA Network Open Journal, researchers from the University of California examined the relationship between daily step patterns and adult mortality.

Study: Association of Daily Step Patterns With Mortality in US Adults. Image Credit: PeterGudella/Shutterstock.com

Background

Physical inactivity is a significant global public health concern. Numerous academic investigations have utilized the quantification of daily steps as a straightforward and reliable metric for physical activity and have explored the correlation between daily step counts and various health outcomes, such as dementia and cardiovascular disease.

A recent meta-analysis has indicated an association between an increase in daily steps and a gradual reduction in mortality risk. This association continues until a threshold of approximately 8,000 daily steps is reached, beyond which the mortality risk remains constant.

It is imperative to provide additional clarification regarding the minimum frequency of weekly walking required to attain health benefits in accordance with the recommended daily step count.

About the study

In the present study, researchers assessed the correlation between adult mortality rates and the duration of time they engage in physical activity, specifically taking 8,000 steps or more per day.

The study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted in 2005 and 2006, which was subsequently linked to the National Death Index until 2019. Out of the total sample of 4,372 individuals aged 20 years or above, 3,120 participants possessed data on wearing an accelerometer for at least four days, which was used to calculate their daily step counts.

From 2005 to 2006, the NHANES requested its participants wear a waist-mounted accelerometer throughout their waking hours for seven days. The study involved the recording of step counts during 60-second intervals every day.

To assess the weekly step patterns, the study incorporated participants who had a minimum of four days with at least 10 hours of wear time, during which the accelerometer recorded step counts. The participants were classified into three groups based on the frequency of achieving a minimum of 8,000 steps per week: zero days, one to two days, and three to seven days.

Results

The mean number of daily steps was almost 8,793 steps. The study revealed that out of the total number of participants, 632 individuals reported taking 8,000 or more steps on zero days per week, while 532 took 8,000 or more steps one to two days per week.

Additionally, 1,937 participants reported taking 8,000 or more steps three to seven days per week. Individuals who engaged in 8,000 or more steps per week were younger, male, of Hispanic ethnicity, insured, married, and non-smokers.

Conversely, they were less likely to report obesity, statins usage, comorbidities, experience mobility restrictions, or rate their health as poor or fair compared to those who took fewer than 8,000 steps for fewer days a week.

During the ten years of observation, 439 fatalities resulting from various causes and 148 fatalities specifically attributed to cardiovascular disease were detected. Upon controlling for potential confounding variables, it was observed that individuals who engaged in 8,000 or more steps for one to two days per week and three to seven days per week exhibited a 14.9% and 16.5% reduction in 10-year all-cause mortality risk, respectively, in comparison to those who did not.

Additionally, individuals who engaged in physical activity by taking 8,000 steps or more for one to two days per week and three to seven days per week exhibited a reduction in 10-year cardiovascular mortality risk by 8.1% and 8.4%, respectively, in comparison to those who did not.

The study also indicated that individuals belonging to both younger and older age groups exhibited a reduced risk of all-cause mortality over ten years when they reported taking 8,000 steps or more either one to two days per week or three to seven days per week, as compared to those who did not engage in any physical activity on zero days per week.

Also, individuals who engaged in physical activity by taking 10,000 steps or more for one to two days per week had an adjusted 10-year all-cause death risk of 8.1%. In contrast, those who reported 10,000 steps or more for three to seven days per week had a lower risk of 7.3%, while those who reported 10,000 steps on zero days in a week had a risk of 16.7%.

Conclusion

The study findings revealed a curvilinear dose-response correlation between the frequency of taking 8,000 steps or more per week and reduced all-cause risks and cardiovascular mortality.

The protective correlation reached a plateau when individuals engaged in a sufficient number of daily steps for three or more consecutive days. The researchers believe that the results indicated that individuals could potentially derive significant health advantages from taking a sufficient number of steps on just a few days of the week.