title: Validity Study of a Jump Mat Compared to the Reference Standard Force Plate.
abstract: BACKGROUND
  In the field of vertical jump diagnostics, force plates (FP) are the reference standard. Recently, despite a lack of evidence, jump mats have been used increasingly. Important factors in favor of jumping mats are their low cost and portability.
  
  
  OBJECTIVE
  This validity study compared the Haynl-Elektronik jump mat (HE jump mat) with the reference standard force plate.
  
  
  METHODS
  Ten healthy volunteers participated and each participant completed three series of five drop jumps (DJ). The parameters ground contact time (GCT) and vertical jump height (VJH) from the HE jump mat and the FP were used to evaluate the concurrent validity. The following statistical calculations were performed: Pearson's correlation (r), Bland-Altman plots (standard and for adjusted trend), and regression equations.
  
  
  RESULTS
  The Bland-Altman plots suggest that the HE jump mat measures shorter contact times and higher jump heights than the FP. The trend-adjusted Bland-Altman plot shows higher mean differences and wider wing-spreads of confidence limits during longer GCT. During the VJH the mean differences and the wing-spreads of the confidence limits throughout the range present as relatively constant. The following regression equations were created, as close as possible to the true value: GCT = 5.920385 + 1.072293 × [value HE jump mat] and VJH = -1.73777 + 1.011156 × [value HE jump mat].
  
  
  CONCLUSIONS
  The HE jump mat can be recommended in relation to the validity of constraints. In this study, only a part of the quality criteria were examined. For the final recommendation it is advised to examine the HE jump mat on the other quality criteria (test-retest reliability, sensitivity change).
authors.affiliation: Department of Health, Discipline of Physiotherapy, Bern University of Applied Sciences, Bern, Switzerland ; Academy for Integrative Physiotherapy and Training Education, Grenzach-Wyhlen, Germany.
authors.forename: Slavko
authors.initials: S
authors.lastname: Rogan
authors.affiliation: Department of Health, Discipline of Physiotherapy, Bern University of Applied Sciences, Bern, Switzerland.
authors.forename: Lorenz
authors.initials: L
authors.lastname: Radlinger
authors.affiliation: Department of Health, Discipline of Physiotherapy, Bern University of Applied Sciences, Bern, Switzerland.
authors.forename: Caroline
authors.initials: C
authors.lastname: Imhasly
authors.affiliation: Department of Health, Discipline of Physiotherapy, Bern University of Applied Sciences, Bern, Switzerland.
authors.forename: Andrea
authors.initials: A
authors.lastname: Kneubuehler
authors.affiliation: School of Health Sciences, University of Applied Sciences and Arts Western Switzerland Valais, Wallis, Switzerland.
authors.forename: Roger
authors.initials: R
authors.lastname: Hilfiker
keywords: Plyometric Exercise; Reproducibility of Results; Sports Medicine