INTRODUCTION. The grip test is usually included in common protocols of functional evaluation. Till today a dynamometer Jamar was used to evaluate Maximum Isometric Strength. At this moment we use isokinetic dynamometers to analyse grip strength in isokinetic way. As a few bibliographic references for this valuation techniques we have designed an study at healthy population to obtain the normal values of grip strength and the influence of individual factors, like sex, age and side-dominance.

MATERIAL AND METHODS. A 321 healthy hands serial was included. The average age was 37.2 years old (ranged 17–63). Mostly of them were men (211 cases, 65.7%). 150 are side-dominant cases (46.7%). All of them has been valuated by Dexter Hand Evaluation. Two speeds 30°/s and 60°/s was used in the study. And the extent used was 4.3 cm. Five trials was done in each velocity. We acquired Maximum Isokinetic Strength and Work.

RESULTS. The values were for strength (Kg) 38.4 at 30°/s and 35.0 at 60°/s and for work (Kg-cm) 98.5 at 30°/s and 86.7 at 60°/s. The side-dominant hand are stronger than non-dominant ones (10.3% in 30°/s, p< 0.001; 11.9% in 60°/s, p< 0.001). Women had less strength than men (37% in both speeds, p< 0.001). The age has less important as isokinetic strength values are more or less the same till 39 years old. After that there is a slow drop of the strength in aged cases.

At last we show tables of normal values at healthy population. The influence of sex and side-dominant are shown as a percentile distribution.

CONCLUSIONS. The isokinetic strength evaluation of hand grip is a very value method in the functional evaluation of the hand. This study gives normal values in healthy hands and the influence of sex, age and side-dominance.