Academic paper clarifies the basis

Published in Cell magazine’s sister magazine “Heliyon”.

Characteristics of cadence during continuous walking in daily life
https://doi.org/10.1016/j.heliyon.2024.e29969

There have already been many academic studies that have demonstrated that walking speed is deeply related to human health, serious diseases, and healthy life expectancy.
It has been demonstrated that a new, previously undiscovered phenomenon exists in which cadences (number of steps per minute) unique to each person occur significantly and frequently in daily life.
This inherent cadence remains constant in the short term, but gradually declines as walking ability declines with aging.
This inherent cadence can be measured very accurately, making it possible to detect slight changes that were previously impossible.
As a result, by tracking the aging process numerically, it becomes possible to detect and notice early signs of decline in walking ability, which is often overlooked, from the healthy period (approximately age 50) to the stage of frailty. And early handle when it is still easier to recover can be realized.

Walking speed can be calculated as [cadence]*[step length]. The walk ratio defined as (step length/cadence) is constant (approximately 0.006) in the short term regardless of speed.
Therefore, walking speed = [cadence squared]*[walk ratio], and walking speed can be calculated from the cadence.
In other words, changes in walking speed, which are closely related to health, can be calculated by changes in cadence.
To be more specific, all people’s cadence is around 120 steps/min (5km/h) when they are healthy, but when they become frail or at risk of frailty, their cadence drops to around 100 steps/min (3km/h). It has now become possible to accurately track changes that are only about 20% (40% in speed) during that time.
Even the slightest recovery in walking ability can be confirmed numerically, and it is expected that the one’s motivation to recover will be maintained and improved. The effects of recovery measures such as exercise and supplements can also be confirmed numerically.