Normative hand grip strength and prediction models for Iranian office employees

BACKGROUND: Normative data on Hand grip strength has a wide range of application and is of great value. OBJECTIVE: To establish gender and age-specific reference data concerning hand grip strength of Iranian office workers, to explore possible relationships with demographic and anthropometric factors and to develop appropriate predictive models. METHODS: The study population included 418 (220 males and 198 females) Iranian office employees. They were divided into 5-year age-groups. Hand length, palm width, palm length, forearm length, wrist circumference, and forearm circumference were measured by means of a digital Caliper (±0.01 mm) and a tape meter (±0.1 cm). The value of hand grip strength was measured by JAMAR hydraulic dynamometer respecting the American Society of Hand Therapy recommendations. RESULTS: The average of grip strength for dominant and non-dominant hands (in Kg) respectively was 51.10±9.50 and 46.90±9.89 for male and 28.76±4.47 and 25.89±4.60 for female. Age was curvilinearly related to hand grip strength. All selected hand dimensions were highly correlated with grip strength; palm width, palm length and hand length being the most correlated ones, respectively. Prediction equations of hand grip strength were developed for dominant and non-dominant hands of both genders. CONCLUSIONS: Suggested norms would provide more accuracy for ergonomic designers as well as health practitioners especially with regards to proposed prediction models with which grip strength could be estimated faster and easier.