Reference Values for Maximal Isometric Handgrip and Pinch Strength in Healthy Italian Adults Without Occupational Biomechanical Overload

Background: Handgrip strength (HGS) and pinch strength are key indicators of hand function with relevant clinical and ergonomic implications. In Italy, normative reference values based on combined measurements of grip and pinch strength in healthy adults not exposed to upper-limb biomechanical overload are currently lacking. The primary aim of this cross-sectional study was to provide descriptive reference values for HGS and three pinch types, stratified by sex and age group, in a healthy Italian adult population (18-65 years) not exposed to occupational biomechanical overload. The secondary aim was to investigate the influence of sex, age, body mass index (BMI), and hand dominance, as well as the relationships among strength measures. METHODS: A total of 813 participants (319 men and 494 women) were evaluated. Measurements were performed using a calibrated Baseline® hand dynamometer and pinch gauge according to the standardized protocol of the American Society of Hand Therapists (ASHT). RESULTS: Men showed higher strength values than women across all measures. The association between body mass index (BMI) and strength was more pronounced and consistent in women than in men, reaching statistical significance only for selected pinch measures in males. Strength values showed a non-linear distribution across age groups, with peak levels observed between 30 and 49 years in men and between 40 and 49 years in women. Hand dominance showed a selective effect in both sexes, influencing specific pinch tasks but not handgrip strength. CONCLUSIONS: This study provides the first national joint normative dataset for intergrip and pinch strength in healthy Italian adults aged 18-65 years not exposed to occupational biomechanical overload. These findings may support clinical and occupational assessments and contribute to the development of broader Italian normative reference tables.