- 2002-2003 ski season 384 skiers were admitted to hospitals with 81% of these being downhill skiers.
- A larger proportion of these admissions were less experienced skiiers.
- The major cause of downhill skiing injury was falls (73%), followed by collisions with objects or persons (18%). The most common injuries to downhill skiers are fractures (61%), dislocations/sprains/strains (14%) and head injuries (7%).
- Almost one-third of injuries were to the knee and lower leg (32%).
- Inadequate release of bindings has been found to cause many lower limb injuries. Binding release performance may be influenced by the quality and conditions of the binding, inadequate adjustment and the condition of the ski boot sole.
Victorian hospital surveillance data.To understand where things go wrong, we need to start with the demands skiing has on our bodies. With majority of incidences being lower-limb injuries resulting from falls, we will explore the basics of lower limb biomechanics, how to test for areas of limitation, and how to improve on these over the next two months.
During the straight-forward stance, generally the weight of the body should sit just over the front of the boots to allow equal distribution of weight through the entire ski. In this stance, your hips, knees and ankles are flexed to allow for absorption of incoming forces and prime the body to respond appropriately. As the slope flattens off (gradient decreases), you will need to lean forward to keep the centre of mass over the front of the skis. Here is where limitations in ankle mobility may ruin your gnarly run.
A well fitted boot should allow for flex (dorsiflexion) to happen at the ankle. The appropriate flex of the boot is determined by a person’s weight, height and skill level. (Check with your preferred manufacturer or ask in store about the Dynamic Response number suitable for your needs.) However, if after all of this your dorsiflexion range still does not allow you to bring your weight through the front of the boots, this could be due to reduced ankle mobility.
A simple way to test for ankle mobility is the Knee to Wall Test. Start by facing a wall with your tested foot in front. While keeping your foot flat on the ground, lunge forward – bringing your knee towards the wall. If your heel lifts while reaching the wall, bring your foot closer to the wall. If you are able to easily reach the wall, bring your foot further away. Find the distance at which you can reach the wall just before the heel lifts. This value is your result. Generally, 5-10cm is an acceptable range; with <5cm being restricted and >10cm being quite mobile.
If you have found that you are restricted in this motion, your first plan of attack can be a simple calf stretch. (Shown Below).
Option 1: Standing in a lunge position with front knee bent and back knee straight. Keep your back heel on the ground and lean forward until you feel a stretch in the lower leg. If you can not keep your heel on the ground you may need to shorten your stance.
Option 2: Using a step or large book stand with you heel hanging off the back and leg straight to stretch your calf.
Hold the stretch for 30 seconds and perform 3 – 5 repetitions each side.
General recommendations by Sport Medicine Australia
- Undertaking appropriate pre-season conditioning and training to build up your fitness, strength and flexibility.
- Warm up and stretch before the day’s skiing. Don’t ski to warm up. Cool down for about 10-15 minutes after a skiing session and include low-intensity exercise such as walking and stretching.
- Novice skiers should undertake skiing lessons, to learn proper use of equipment, improve skills and techniques, and learn skiers’ etiquette.
- Assess the snow conditions and take them into consideration, along with your skill level, before skiing.
Sports Medicine Australia: Downhill Skiing Fact Sheet (2013).
Warren-Smith Ski Academy: Ski Biomechanics and Range Test