Total Steps vs. How You Get Them and the Risk of Cardiovascular Events

By Michael H. Crawford, MD

Synopsis: In a large U.K. Biobank study of subjects who performed a one-week determination of steps/day, those who achieved < 8,000 steps/day were categorized by the duration of their step acquisition periods and were followed for a mean of eight years. All-cause mortality and the development of cardiovascular disease (CVD) were greater in those with short step acquisition periods (< 5 minutes) as compared to those with longer periods (> 15 minutes). Thus, longer step acquisition bouts are more effective in reducing mortality and CVD in those with less-than-ideal total daily step counts.

Source: Del Pozo Cruz B, Ahmadi M, Sabag A, et al. Step accumulation patterns and risk for cardiovascular events and mortality among suboptimally active adults. Ann Intern Med. 2025; Oct 28. doi:10.7326/ANNALS-25-01547. [Online ahead of print].

In suboptimally active subjects (< 8,000 steps/day), it is unclear whether the total number of steps or their accumulation in longer bouts of exercise is more important for preventing cardiovascular disease (CVD) and mortality. Thus, these investigators from the U.K. Biobank conducted a prospective observational study of 103,684 participants recruited between 2006 and 2010 who, during 2013 to 2015, agreed to wear a wrist accelerometer for seven days. The 33,560 subjects (mean age 62 years, 41% men) who wore it for at least three days for 16 hours or more and which included at least one weekend day were included in the study. Excluded were those with known CVD or cancer.

Those with < 8,000 steps/day on average were included in the analysis. Their stepping bouts were divided into four categories: < 5 minutes, 5 to < 10 minutes, 10 to < 15 minutes, and > 15 minutes. The < 5-minute group included 43% of the patients; the 5- to < 10-minute group, 33%; the 10- to < 15-minute group, 15%; and the >15-minute group, 8%. All the subjects were followed until 2022, and clinical data were obtained from the U.K. National Heath Service. All-cause mortality and CVD incidence were the primary endpoints. The development of systemic hypertension was not considered CVD. Sensitivity analyses were performed on important confounding conditions, such as frailty, waist circumference, lipids, hemoglobin A1c, and walking pace. To account for residual confounding, the results were compared to a negative control group consisting of patients who died from accidents.

During the average follow-up of eight years, 735 subjects died and 3,119 had a CVD event. Mortality decreased with increasing bout length. For bouts < 5 minutes, it was 4.4%; 5 to < 10 minutes, 1.8%; 10 to < 15 minutes, 0.84%; and > 15 minutes, 0.80%. Total step count also affected the results. In the < 5,000 steps subgroup, mortality was 5.1% in the < 5-minute group and 0.86% in the > 15-minute group. In the 5,000 to 8,000 steps/day group, it was 2.5% in the < 5-minute group and 0.72% in the > 15-minute group.

CVD events followed a similar pattern: < 5 minutes, 13%; 5 to < 10 minutes, 11%; 10 to < 15 minutes, 8%; and > 15 minutes, 4%. In the < 5,000 steps/day group, CVD developed in 15% of the < 5-minute group and in 7% of the > 15-minute group. In the 5,000 to 8,000 steps/day group, CVD developed in 9% of the
< 5-minute group and in 4% of the > 15-minute group. None of the sensitivity analyses changed the results.

The authors concluded that those who achieved < 8,000 steps/day who achieved most of their steps in longer bouts had a reduced risk of all-cause mortality and CVD events. These risk reductions were greatest in those who achieved < 5,000 steps/day.

Commentary

The widespread use of wearable step-counting devices has led to interest in the step count goals associated with better health. Previous studies have shown that the health benefits of step counts start at about 2,600 steps and plateau at around 8,000 steps. Thus, < 8,000 steps/day is considered suboptimal. However, a substantial portion of daily steps do not come from prolonged walks (> 10 minutes). So, the question arises as to whether the total steps/day or the duration of sustained bouts of steps is more important. This is particularly important for those with the least amount of exercise/day. It has been hypothesized that longer bouts are more likely to improve glucose metabolism by enhancing skeletal muscle uptake of glucose.

Another consideration is the intensity of exercise. Is walking leisurely for > 8,000 steps the same as climbing hills or walking stairs or running for the same number of steps? Most of the stepping in this study was considered light to moderate exertion, but when analyzed by those who claimed a brisk walking pace, the results were similar. Also, the biggest difference in outcomes was observed when < 5-minute bouts were compared to longer bouts, which suggests that longer bouts were purposeful exercise for fitness.

In addition, the biggest differences in outcomes were observed with CVD development, not mortality, which supports a cardiometabolic effect of longer bouts. Finally, those who exercise for longer periods also may do strength exercises, which would augment the overall benefits. Conversely, those with shorter bouts may have other health limitations, which would reduce the observed benefits.

There are limitations to this study to consider. Observational studies can be weakened by reverse causation and residual confounding. However, the large size of the study and the sensitivity analyses of potential confounders are reassuring, as is the exclusion of those with CVD, cancer, and frailty. Step counts were done over a relatively short period of time and assumed to be constant for the long duration of the study. All covariates were determined once at baseline. Exercise intensity and other types of exercise were not assessed. However, the observed progressive decrease in mortality and CVD with longer bouts of stepping is reassuring.

Michael H. Crawford, MD, is Professor Emeritus of Medicine and Consulting Cardiologist, UCSF Health, San Francisco.