Biomechanical Adaptations to an Implemented Ramp Angle in Recreational Alpine Skiers

Most ski boot-binding complexes have a negative ramp angle. This angle is not regulated or reported in the alpine ski industry, but may influence skier balance and pressure control. Thus, joint coordination and center of pressure maintenance in alpine skiers (n = 19) was investigated during simulated ski squat and balance tasks with increasing binding ramp angles (0°, 1°, 2°). Greater sagittal plane center of pressure excursions were observed with ski-booted tasks compared to barefoot conditions during squats and balance simulations. Squat tasks performed on skis resulted in more uncoordinated knee-ankle movement, however, this effect was reduced with the highest ramp angle. Further, increased hip driven movement coincided with decreased coordinated hip-knee movement. Barefoot balance tasks resulted in a reduced knee (knee-ankle coordination) and increased hip contribution (hip-knee coordination). Excursions during trials with higher ramps were more likely to be significantly greater than when barefooted. In conclusion, the addition of a boot-binding complex appears to increase sagittal plane excursions, increase uncoordinated movement (squat tasks), and reduce knee joint driven postural maintenance (balance tasks). Higher degrees of ramps may be associated with altered joint coordination that does not positively affect squat pressure maintenance, as well as reduced sagittal plane stability during balance challenges