Mid Sweden University

Aim

To assess the effect of rifle carriage on skiing performance and angular kinematics in biathletes,and whether the rifle’s effect on angular kinematics could explain its effect on skiing performance, under ecologically valid conditions.

Methods

Twenty-nine biathletes (11 females, 18 males) performed two maximum effort skiing time-trials on snow, once with and once without rifle. During time-trials, biathletes wore a three-dimensional motion analysis system to measure maximum angle, minimum angle and range of motion of knee, hip and elbow flexion. A two-way mixed model analysis of variance and multilevel linear model were used to assess the effect of rifle carriage on skiing performance and angular kinematics respectively. In case of a significant effect, a Pearson correlation coefficient was calculated to assess the relation between the rifle’s effect on the respective angular measure and the rifle’s effect on skiing speed.

Results

Skiing performance was impaired with rifle compared to without rifle (P<.001; ƞ2p=0.04). No effect of rifle carriage was observed on any angular measure, except for maximum elbow flexion(P=.03; Cohen f 2<0.01). Maximum elbow flexion was reduced with rifle compared to without rifle (mean difference 11.9±37.6°). Pearson correlation coefficient revealed a positive correlation between the rifle’s effect on maximum elbow flexion and its effect on skiing speed (r=0.19; P=.04).

Practical application

The results demonstrate the negative impact of rifle carriage on biathlon skiing performance and suggest that maximum elbow flexion plays a role. Therefore, upper body contributions, elbow flexion angles in particular, might be of interest for biathlon coaches.