Why Skate Uphill? A Biomechanical Analysis of the Effect of Incline on Forward Skating Mechanics

Abstract

The purpose of the study was to investigate the effect of surface incline on lower body kinematics and kinetics during forward skating at a constant speed on a skating treadmill. Fourteen male, competitive hockey players were recruited to participate (mean age: 23  2 yrs). An ABA, within-subject, quasi-experimental design was conducted to compare skating mechanics between four (A) baseline incline conditions (2 deg incline) and three (B) experimental incline conditions (6, 9, 12 deg inclines). An XSENS Awinda (XSENS Technologies, Enschede, The Netherlands) IMU sensor system and XSENSOR X4 (XSENSOR Technology Corporation, Calgary, Canada) pressure insoles were used to collect kinematic and kinetic data concurrently. Repeated measures ANOVAs across the repeated baseline incline conditions revealed no significant differences in any of the kinematic or kinetic variables, providing confidence that any changes in skating mechanics could potentially be a result of the increased incline conditions. Repeated measures ANOVAs revealed significant differences in stride length (m), stride rate (strides/s), support and recovery times (s), hip and knee flexion at weight acceptance (deg), maximum ankle dorsiflexion (deg), peak hip and knee flexion and extension angular velocities (rad/s), peak push-off force (N) and impulse (Ns) between the baseline incline condition and each of the experimental incline conditions (p<0.05). Further, repeated measures ANOVAs also revealed significant differences in stride rate (strides/s), support time (s), peak hip and knee flexion angular velocities (rad/s) and impulse (Ns) across each of the experimental incline conditions (p<0.05). This suggested that not only the incline but also the magnitude of incline has the potential to elicit different mechanical changes. These findings provide support for the manipulation of treadmill surface incline as a biomechanical stimulus to elicit changes in skating mechanics.