Muscle force is considered to be an important determinant for physical performance, activities of daily living, and work or sport performance . Several processes such as aging, development of pathological symptoms, or injury may result in reduced muscle force. It is important for clinicians as well as physical therapists, orthopedists, or rehabilitation specialists to obtain insight into a patient’s muscle force. Muscle force can be reliably measured with a handheld dynamometer. To put an individual’s muscle strength into perspective, measurements must be compared with reference values. MuscleNorm provides the possibility to instantly compare the outcomes of muscle force measurements obtained with a handheld dynamometer with specified reference values. Additionally, it calculates the predicted muscle force based on age, weight, and gender. This value is positioned and graphically displayed in the 95% prediction interval. MuscleNorm provides calculations in pounds, kilogram’s and newton and allows personal muscle force calculations and comparisons according to Dutch or American values.

The app for the Dutch reference values is based on: Douma KW, Soer R, Krijnen WP, Reneman M, van der Schans CP: Reference values for isometric muscle force among workers for the Netherlands: a comparison of reference values.; BMC Sports Science, Medicine and Rehabilitation; 2014, 6:10. For the American reference values, it is based on: Bohannon RW, Ed D: Reference values for extremity muscle strength obtained by hand-held dynamometry from adults aged 20 to 79 years.Arch Phys Med Rehabil 1997, 78:26–32.

Rob K.W. Douma

Lecturer/Researcher Physiotherapy

Hanze University Groningen, University of Applied Sciences

Research group for Healthy Ageing, Allied Health Care and Nursing.

University Medical Center Groningen, dept of rehabilitation.

University of Groningen

Tel: 0031(0)505957700.


K.v.K. Groningen: 02096258 | BTW NL8254.03.522.B01