Jumping Mechanography: Reference Centiles in Childhood and Introduction of the Nerve-Muscle Index to Quantify Motor Efficiency.


Jumping mechanography provides robust motor function indicators among children. The study aim was to develop centiles for the single 2-leg jump (S2LJ) in German children and adolescents and to identify differences in children with obesity. Data were collected in 2004-2021 through the German DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) study. All participants (6-18 years, mean age 11.4) performed annually an S2LJ aiming for maximum height on a Ground Reaction Force Platform. LMS (lambda-mu-sigma), including resampling, was used to develop centiles for velocity (v(max)), jump height (h(max)), relative force (F(max)/BW), relative power (P(max)/mass), impulse asymmetry and a new parameter to describe jump efficiency, the Nerve-Muscle Index (NMI), defined as v(max)/(F(max)/BW). Data from 882 children and adolescents were analyzed (3062 measurements, median 3 per individual). In females, F(max)/BW values were higher in younger age but remained constant in adolescence. v(max), h(max) and P(max)/mass increased in childhood, reaching a plateau in adolescence. In males, v(max), h(max) and P(max)/mass showed a constant increase and the F(max)/BW remained lower. Children with obesity showed lower F(max)/BW, h(max), v(max) and the NMI, hence, lower velocity per relative force unit and less efficient jump. The centiles should be used to monitor motor development in childhood. The NMI is a surrogate for motor efficiency.

Author: Martakis K, Alexy U, Stark C, Hahn A, Rawer R, Duran I, Schonau E

Organization: Department of Pediatrics, Faculty of Medicine and University Hospital Cologne, Kerpener Strasse 62, 50937 Cologne, Germany.

Year: 2023

GID: 6072

Created on: 09.10.2023

The verdict of our customers: Excellent


4.7 out of 5 stars based on 868 reviews

TÜV certified

We are a TÜV certified manufacturer for medical products.

Made in Germany

Development and manufacturing in Germany.

Proven quality

10 years service guarantee & more than 35 years experience in the company group.

Research studies

over 2000 scientific publications about our products.

Active worldwide

Internationally active with our distribution partners.

Start typing to see posts you are looking for.