Can I convert the grip strength in kPa to kg?

Eforto® measures dynamic grip strength in units of pressure, specifically kilopascals (kPa), which represent force per unit area. While we do have a conversion factor to kilograms, the measurement dynamics of the Eforto® Device differ from those of hydraulic systems. The Eforto® App and Eforto® Metrics can automatically display estimated values in kilograms, which is useful at the population and cohort levels but less advisable for individual subjects, as the conversion is based on an estimation.

One of the causes of estimation error can be due to the fact that measurements with the traditional dynamometers are more influenced by the morphology of the hand compared to the bulb-based pneumatic Eforto® Device/Vigorimeter.

We have validated normative data for the Eforto® Device for grip strength with thresholds/cutoffs for sarcopenia, as well as for muscle fatigability and CPV ratio as an indicator of Vitality Capacity and early signs of Frailty.

The conversion formula to go from a result in kPa to a result in kg is as follows:

Estimation in kg = result in kPa * 0.43