Step Count or Time? New Study Suggests Both Equally Beneficial for Health

Krissy Vann | Host, All Things Fitness and Wellness

In the age of smartwatches, tracking step counts has become easier than ever. However, current physical activity guidelines do not specifically recommend step counts for health. A recent study by researchers at Brigham and Women’s Hospital, a founding member of Mass General Brigham, reveals that both step and time-based exercise targets are equally associated with reduced risks of early death and cardiovascular disease. Therefore, choosing between a time or step goal may be less important than selecting a goal that fits personal preferences. The findings are published in JAMA Internal Medicine.

Physical activity is known to reduce the risk of chronic illness and infection and promote longevity. The current U.S. guidelines, last updated in 2018, advise adults to engage in at least 150 minutes of moderate to vigorous physical activity (e.g., brisk walking) or 75 minutes of vigorous activity (e.g., jogging) per week. At the time, most evidence on health benefits was based on studies where participants self-reported their physical activity, with few data points on the relationship between steps and health. Today, with wearables being ubiquitous, step counts have become a popular metric among many fitness tracking platforms. Researchers aimed to compare the effectiveness of time-based goals with step-based ones.

“We recognized that existing physical activity guidelines focus primarily on activity duration and intensity but lack step-based recommendations,” said lead author Rikuta Hamaya, MD, PhD, MS, a researcher in the Division of Preventive Medicine at BWH. “With more people using smartwatches to measure their steps and overall health, we saw the importance of ascertaining how step-based measurements compare to time-based targets in their association with health outcomes – is one better than the other?”

For this study, researchers gathered data from 14,399 women who participated in the Women’s Health Study and were healthy (free from cardiovascular disease and cancer). Between 2011 and 2015, participants aged 62 years and older were asked to wear research-grade wearables for seven consecutive days to record their physical activity levels, only removing the devices for sleep or water-related activities. Annual questionnaires were administered to ascertain health outcomes of interest, particularly death from any cause and cardiovascular disease. The participants were followed through the end of 2022.

At the time of device wear, researchers found that participants engaged in a median of 62 minutes of moderate-to-vigorous intensity physical activity per week and accumulated a median of 5,183 steps per day. During a median follow-up of nine years, approximately 9% of participants had passed away, and roughly 4% developed cardiovascular disease. Higher levels of physical activity (whether assessed as step counts or time in moderate-to-vigorous activity) were associated with significant risk reductions in death or cardiovascular disease – the most active quarter of women had 30-40% risk reductions compared with the least active quarter. Moreover, individuals in the top three quartiles of physical activity outlived those in the bottom quartile by an average of 2.22 and 2.36 months respectively, based on time and step-based measurements, over nine years of follow-up. This survival advantage persisted regardless of differences in body mass index.

While both metrics are useful in portraying health status, Hamaya explained that each has its advantages and downsides. Step counts may not account for differences in fitness levels. For instance, if a 20-year-old and 80-year-old both walk for 30 minutes at moderate intensity, their step counts may differ significantly. Conversely, steps are straightforward to measure and less subject to interpretation compared to exercise intensity. Additionally, steps capture even sporadic movements of everyday life, not just exercise, and these kinds of daily activities likely are those carried out by older individuals.

"For some, especially younger individuals, exercise may involve activities like tennis, soccer, walking, or jogging, all of which can be easily tracked with steps. However, for others, it may consist of bike rides or swimming, where monitoring the duration of exercise is simpler. That's why it's important for physical activity guidelines to offer multiple ways to reach goals. Movement looks different for everyone, and nearly all forms of movement are beneficial to our health,” said Hamaya.

The authors note that this study incorporates only a single assessment of time and step-based physical activity metrics. Further, most women included in the study were white and of higher socioeconomic status. Finally, this study was observational, and thus causal relations cannot be proven. In the future, Hamaya aims to collect more data via a randomized controlled trial to better understand the relationship between time and step-based exercise metrics and health.

Senior author I-Min Lee, MBBS, ScD, an epidemiologist in the Division of Preventive Medicine at BWH, concluded, "The next federal physical activity guidelines are planned for 2028. Our findings further establish the importance of adding step-based targets, in order to accommodate flexibility of goals that work for individuals with differing preferences, abilities and lifestyles."

Elevate Your Expertise: Tune in to Our YouTube Channel for Exclusive Podcasts with fitness and wellness Industry Titans and Game-Changers