The authors identified both minimal and optimal targets that were independent of gender and device location (i.e., a device worn on the hip vs. wrist), although additional benefits were observed when walking at a faster pace. On the low end, this study suggests walking a minimum of 2,517 or 2,735 steps per day, which was associated with an 8% reduction in all-cause mortality and 11% in CVD incidence, respectively. An optimal target was suggested to be 8,763 and 7,126 steps, which predict 60% and 51% reductions in all-cause mortality and CVD incidence, respectively.
This is not to say that additional benefits don’t occur at even higher levels of activity, only that the returns start to diminish. For example, at 16,000 steps per day (roughly double the optimal target) the reduction in all-cause mortality and CVD incidence only decreases by an additional 5-7%. It’s also important to note that benefits did occur (non-linearly) with increments of even 500 steps per day, providing incentives for people at even low levels of activity. An unrelated randomized controlled trial published in the Journal of Applied Physiology (with only 10 participants) offers possible mechanisms; 10,000 steps vs. 2,000 steps per day, for instance, reduced post-prandial lipemia at the evening meal of the same day, a risk factor for CVD.