The squat is one of the best exercises for athletes and the general population because it not only allows you to run faster and jump higher, but it also strengthens bone and can improve mobility and walking speed. Everyone should train some form of squats, but the exact type of squat that is best for each trainee may vary, according to new research in the Journal of Sports Rehabilitation.
In this study, researchers tested how lack of flexibility in the ankle joint alters a trainee’s movement pattern in the squat, putting them at risk of injury. The theory is that tight calves, which cause the shin to stay closer to vertical during the squat, will limit the ability of the lower limb to track properly.
Researchers had subjects perform body weight squats with the sole of the feet flat on the ground in neutral position or with the ankle dorsiflexed 12 by placing the foot on a wedge board (the slant faced towards the subject). Results showed that with the foot dorsiflexed on the wedge board, the knee valgus angle, or “caving inward,” of the knee increased 16 percent on a wedge board compared to feet flat on the ground. Muscle activity of the soleus increased, while the activity of the quadriceps muscles, especially the vastus medialis obliquus (VMO) decreased.
These findings demonstrate how a trainee with tight calves or lack of ankle flexibility will have incorrect movement patterns during the squat that can put them at risk of injury. Plus, a trainee with limited ankle range of motion will likely already have structural imbalances, particularly of the VMO. Obviously, if they perform squats without correcting for ankle immobility and muscle weaknesses, the problems will only get worse.
Solve this by using the following strategies:
• Do a structural balance assessment for the muscles in the lower body and to identify range of motion (ROM) issues in the ankle and hip joints.
• Train split squats and step-ups to achieve greater structural balance before training a regular squat.
• Perform stretching, soft tissue work, and mobility exercises in joints with limited ROM.
• Train the tibialis anterior—try a machine that is designed to strengthen this muscle, such as the machine made by Atlantis—check out this video ( http://www.youtube.com/watch?v=k5ha7x8mSGE )for an example.
• Ensure the tibialis anterior is firing: Do the eccentric lowering phase of a calf extension and when you reach the bottom position, isometrically contract the tibialis anterior. This will increase the pre-stretch on the gastrocnemius and soleus, activating more motor units in the following concentric contraction of the plantar flexors.
• Once basic structural balance is achieved in the lower body, if ROM is still lacking in the ankle, use a wedge board to increase ankle ROM. Stand on a wedge board with the slant facing away from you in order to plantarflex the ankle, which will increase ROM and allow for better movement patterns in the squat.
• Do one-and-a-quarter squats to strengthen the VMO: Squat all the way down on a 4-second count, come up a quarter of the way at a controlled pace, go back all the way down under control until the hamstring covers the calves, and then all the way up.
Marcum, E., Bell, D., et al. Effect of Limiting Ankle-Dorsiflexion Range of Motion on Lower Extremity Kinematics and Muscle-Activation Patterns During a Squat. Journal of Sport Rehabilitation. 2012. 21(2), 144-150.