Unfortunately, the most common injury among wakeboarders happens to be tearing or rupturing of the ACL. The ACL connects the front of the shin bone, or tibia, to the back of the thigh bone, or femur. This stabilizes the knee joint and prevents the knee from hyperextending. Tearing the ACL happens from deceleration, like landing a jump or a trick, or from a twisting or shifting movement with the leg attached and anchored to the wakeboard. Bindings make us particularly more vulnerable to stress and tearing of the ACL. The ACL is most weak when the feet are pointed outward, knees inward, and torso flexed forward.
How can you protect the ACL? Multiple factors are involved with stabilizing and conditioning the knee. Strengthening the surrounding musculature is most important to help decrease the stress to the ACL involved with deceleration in the knee joint. This includes the quadriceps, hamstrings, hip abductors, hip external rotators, abdominals and obliques. The muscles assist in stabilizing the knee and prevent hyperextension. Below are a few exercises to add to your normal routine to make sure you protect your knees!
1. Body Weight Squats: Begin with knees and ankles separated, shoulder width apart, standing straight up. Hands can be on the waist or out in front for balance. Bend at the hip and knee, pushing buttocks backward like sitting in a chair. Make sure your knees don’t push forward of ankles. Return to stand. Repeat 25 times.
2. Heel Pulls: Lying on the floor, place one heel on top of a small plate weight (begin with 10 lbs). Stabilizing with your hands against the floor near your hips, pull heel with weight towards your buttock then back down to start position. Repeat 10 times per leg.
3. Box Step: Stand in front of a box, chair, or bench about 2 feet high. Step up onto the box, straighten the knee and step back down. Repeat on both legs 15-20 times. When this exercise becomes easier, add dumbells to hands.
4. Abductor Lifts: Lying on your side with bottom leg bent and top leg straight, lift top leg up. Hold for 3-5 seconds and lower to starting position. Repeat 15-20 times and repeat on opposite leg. Ankle weights will increase the intensity.
5. Adductor Lifts: Lying on your side with bottom leg straight and top leg bent and planted in front, lift bottom leg and hold for 3-5 seconds. Lower to floor and repeat 15-20 times. Repeat on opposite leg. Ankle weights will increase the intensity.
The next step in preventing ACL injury is to add coordination and proprioceptive exercises to help with the dynamic, or moving, strength of the knee, like in jumping and landing. Focus and attention should be made on maintaining an upright torso, increased knee flexion or bend, and lowering the center of gravity to help absorb the deceleration, both in the exercises and in landings behind the boat or cable.
1. Box Jumps: Stand in front of a box, chair or bench. Jump up with two feet to stand. Jump back down. Special attention should be made on bending the knees and absorbing the landing. Repeat 15-20 times.
2. Bosu/Indo Squats: Stand on the wobble board side of the Bosu ball or on top of an Indo board. While maintaining a tight core, bend at the waist and knee into a controlled squat and return to standing. Make sure chest is up and knees are not bowing in while in the squat position. Repeat 10-15 times.
3. One-Legged Star Plyometrics: Begin the 4 star drill by drawing (or imagining) a box on the ground. Each corner of the box will have a number that corresponds to it.
Perform the 4 star drill by hopping from one spot to the next. You can follow the order from 1 to 4, or you can change the order for some variation. You can also add a fifth spot at the center for even more difficulty.
Keep your ACLs protected and strengthen those knees!