Objectives: The aim of this field study was to explore the relationship between body mass and quad bike
induced whole-body vibration (WBV) exposure in a group of New Zealand rural workers.
Methods: WBV exposure was recorded using a seat pad mounted tri-axial accelerometer while rural workers (n=34) were
driving a quad bike for approximately half an hour on a pre-marked track on farm terrain. Personal factors such as age,
height and quad bike driving experience were also surveyed and included as co-variates. Vibration dose value (VDV) was
calculated by analyzing the recorded raw vibration data samples (n=34) using vibration analysis software and corrected to
a one hour equivalent exposure for further statistical analysis. To evaluate for the relationship between variables of
interest (body mass, height, age and driving experience) and one hour VDVZ (1hrVDVZ), univariate and multivariate
linear regression analysis were conducted.
Results: Mean 1hrVDVZ was 13.2 m/s1.75 exceeded the VDV exposure action value of 9.1 m/s1.75. Univariate analysis
demonstrated body mass (R2 = 0.340) significantly (p < 0.0003) associated with 1hrVDVZ while age, body height and
quad bike driving experience were not. In a multivariate backward linear analysis body mass, height, and experience
combined to explain 38% (R2 = 0.376) of the variance in 1hr VDVZ, however, only body mass (p= 0.0004) demonstrated
statistical significance.
Conclusion: Body mass is significantly and negatively associated with quad bike induced WBV (1hrVDVZ) in a group of
New Zealand rural workers.