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  The Anterior Cruciate Ligament (ACL) is located in the center of the knee. The function of the ACL is to prevent the tibia from moving ahead of the femur. If the ACL tears or fails to perform properly, then you will not be able to withstand any pressure on that knee. Many athletes experience ACL tears and must perform advanced ACL rehab exercises, after treatment by a doctor, to re-stabilize the knee.
  
  

Lunges

• Stand with both feet shoulder width apart. Slightly bend both legs. Step two feet forward with the right foot. Lower the left leg one foot above the floor while bending the right leg to reach a perpendicular stance with the ground. Hold the stretch for 10 seconds. Slowly return your left leg and your right foot to the starting position. Switch legs and repeat the same moves. Repeat the process five times.
  
  

Chair Bends

• Stand with both feet together. Step to the left two feet with your left foot. Then move your right foot near your left foot with a one-foot gap between feet. Slowly bend both knees perpendicular to the floor. Hold the pose for five seconds. Slowly stand straight up. Step to the right two feet with your right foot. Repeat the process on the opposite side. Repeat the cycle five times.
  
  

Side Hop

• Stand with both legs together. Hop to the left with both legs still together. Hop to the right with both legs still together. Repeat the hopping sequence 20 times.
  
  

Stair Climbing

• Sit on the floor and slowly lower the back to the floor. Put both hands flat on the ground underneath the buttocks. Lift both feet two-inches above the ground. Raise the shoulders two-inches from the ground. Slowly bend both legs at the knees and bring them towards the chest. Slowly re-straighten both legs and lower them to the ground. Lower the shoulders back to the ground. Repeat the process five times.
  
  

Bicycle

• Sit on the floor with both legs straight and toes towards the ceiling. Place both hands, palm down on the floor, behind the back. Slowly bring the right leg towards the body by bending the right knee. Lower the right leg back to the ground and raise the left knee to bring the left leg towards the body. Repeat switching legs 20 times.
  
  

Quad Stretch

• Lay flat on the floor facing the ceiling. Bend the left leg and hold the left foot with the left hand. Hold the pose for 10 seconds. Repeat with the right leg. Continue alternating 20 times.