December marks the beginning of the ski season in most European and American ski resorts. Many clients want to know what they can do to reduce their risk of ski injury. Here are some helpful tips based on recent research.
What are the most common skiing injuries?
The most common injuries for skiers are knee injuries. The Medial Collateral Ligament (MCL) on the inside of the knee is most vulnerable to injury. A rupture of the Anterior Cruciate Ligament (ACL) inside the knee is slightly less common but usually a more serious injury. These ligament injuries can occur in isolation or may be associated with damage to the menisci-the cartilage wedges between the knee joint surfaces.
What can I do before my ski trip to reduce my risk of injury?
Skiing is a physical activity which requires endurance of many muscle groups. EMG activity of skiers when turning shows high activity of the abdominal, back and leg muscles, especially the quadriceps. Improving the endurance capacity of these muscle groups can help to delay fatigue and ensure you maintain a good technique towards the end of a hard day on the slopes, reducing your risk of falling. A good conditioning programme is important, particularly if you are not already engaged in a regular exercise programme.
Sports Injury bulletin recommend the following exercises as preparation for skiing fitness.
- Parallel squat – 3 sets of 20
- Ab crunch- 3sets of 20
- Dead lift- 3 sets of 20
- Twisted crunch -3 sets of 20
- One-footed calf raise-3 sets of 20
- Back raise on floor (hands by ears).3 sets of 20
- Single leg squats 3 sets of 10 each side
- One legged chop Stand on one leg and bend forward from hips, keeping your back straight. 3 sets of 10 each side
It is a good idea to include some balance and proprioceptive exercises as well as some skiing specific movements. Your physiotherapist can also design a more specific programme which takes into account any individual weaknesses which may be relevant.
What about my equipment?
Lots of research has looked at the relationship between ski bindings and knee injuries. A good ski hire shop should take measurements of your height and weight in order to set your bindings to the correct stiffness. Ideally bindings should be set to allow release of your skis in the event of a fall. If a ski doesn’t release there is risk of greater twisting forces increasing the risk of injury.
- If you have your own skis you should get the bindings serviced at least once a year. Studies have shown that un-serviced bindings become stiffer and less likely to release if you fall.
- If you are hiring skis you should make sure you give an accurate value for your weight and height and a fair description of your skiing level. Try to hire from a well-equipped shop with a good selection of carver skis to choose from.
- Avoid borrowing skis which have not been fitted for you specifically.
- Remember that your boots are important too. Walking around too much in your boots can wear the soles which can affect the function of the ski binding mechanism. Take care when hiring boots that they do not look too worn in this way.
- Experts recommend you perform a self- test on your ski bindings daily to check the release mechanism. Check the toes piece by angling the inside edge of the ski to the ground and trying to twist the boot inwards by applying gradual force. The toes should twist out of the front of the binding. To check the heel piece, keep the ski flat on the ground and slide your heel back until the back leg is straight. Slowly and gently try to lift the heel of the boot out of the binding. If you can’t release either the toe or heel of the boot in this way you should reduce your binding setting by 0.5 and then repeat the test, adjusting further if necessary. (http://www.bobski.com/safety/french_binding_system_self_test.pdf)
What happens if I do fall?
The most common mechanism of ACL tear occurs where the tail of the downhill ski or ‘phantom foot’ provides a force from the back of the knee as if an imaginary foot were pushing the tail of the ski. This acts as a lever causing twisting and bending torques at the knee joint rupturing the ACL. This situation is more likely to happen when attempting to get up whilst still moving after a fall or as a result of leaning back in your boots or trying to sit down to avoids an inevitable fall. Often people are surprised by how little speed and force is required to rupture this ligament when it is put in this vulnerable situation (www.ski-injury.com)
You can try and avoid injury in this way by keeping your arms and hands forward over your skis when falling, keeping your legs bent, and avoiding standing up if already falling until you have stopped moving completely.
What can I do at the end of the day to recover quickly?
It is a good idea to perform a brief stretching routine each day after skiing to help recovery of the main muscles used. Examples of appropriate stretches are:
- Back stretch-lying on your back with your arms out to each side and your knees bent up. Twist your knees and hips to one side allowing your back to rotate. Hold for a few seconds as is comfortable and repeat several times to each side.
- Hip stretch-knee on one knee and place the other foot in front with the foot flat. Push your hips forwards to stretch the front of your back leg. Hold for 30-60 seconds each side
- Achilles stretch-In standing place the ball of one foot onto a step, bend the knee and lean forwards. Hold for 30-60 seconds each side.
You can also try other recovery strategies such as a light swim which may help metabolise lactic acid built up in the muscles, which is associated with aching and fatigue.
Recreational skiers should also be conscious of the time they are skiing for each day if they want to make it to the end of a week ski holiday without risk of injury. Some experts recommend the rule of 3: a stop before 3 pm each day, avoiding skiing more than 3000m a day and taking the third day off (www.injuryfix.com)
Should I wear a knee support?
Many patients ask whether a knee support can protect them from injury or re-injury. There are many different braces on the market ranging greatly in price. These range from simple neoprene supports to more complex functional made to measure braces. The price is usually a good indicator of how durable and comfortable the material of the brace will be as well as how much protection it will provide. There is some good evidence that made to measure functional knee braces can reduce the stress for the ACL making them useful for people returning to skiing after a reconstruction. Based on this I would recommend patients with reconstructed knee ligaments and patients with known ligament deficiencies consider wearing functional knee braces.
Changes in quadriceps muscle activity during sustained recreational alpine skiing
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