Strengthening exercises can begin as soon as they are pain free to perform. If it hurts, don't do it. In grade 1 tears, strengthening exercises may be started from day 2.
The following examples are for information purposes only. We recommend seeking professional advice before attempting any exercises. If you find you have more pain the following morning after doing strengthening exercises then you may need to reduce the workload.
Static contractions can be used very early on in the rehab process. They involve contracting the muscle without any movement of the leg. This can be done in standing, or sitting with the legs out straight. Hold contractions for 10 seconds at a time. Relax for 5 seconds before repeating and perform 10 repetitions. As your strength improves, increase sets to 2 or 3 sets of 10 reps.
Although this exercise is boring it will maintain muscle bulk and ensure you are back to full fitness faster. Continue with this exercise on a daily basis until you are able to perform the concentric exercises below.
Play isometric quadriceps exercise video.
This exercise can be done lying down or sitting. Lying down is easier. Sit flat on the floor with the legs straight out in front of you. Raise one leg off the floor keeping the knee straight. Hold for 3 to 5 seconds before lowering back to the ground. Repeat 10 to 20 times. This exercise can be done daily. Progress the exercise by increasing the length of hold and the number of reps. Ankle weights can be added to increase the difficulty.
Play straight leg raise exercise video.
The quad muscles are responsible for straightening the knee. This exercise can be performed using no weight, ankle weights, a resistance machine or resistance band. Start with no weight and then progress to either ankle weights or a resistance band. Straighten the knee then slowly return to the start position. Start with 2 sets of 10 reps and gradually increase to 3 sets of 15 gradually increasing the weight or resistance when comfortable to do so.
Play knee extension exercise video.
Lunges are a slightly easier version of a squat and are sometimes called split squats. Start with a wide stance. Bend the back knee towards the floor, but don't let it touch. Keep your back upright throughout and don't let the front knee move forwards past the toes. Start with 2 sets of 10 reps with the injured leg in front and then do 2 sets of 10 with the injured leg behind. Gradually increase to 3 sets of 15. To make it harder, you can add either a dumbbell in each hand of a barbell over the shoulders.
Play lunge exercise video.
Squats can be performed in many ways including ball squats, double leg squats and single leg squats. Fit ball squats are the easiest and so if possible should be performed first, followed by double leg and then single leg as progressions. Ensure you do not bend your knees past 90 degrees and you make sure your knees don't move forwards past your toes. Start with 2 sets of 10 reps and gradually increase to 3 sets of 15 before progressing.
Play squat exercise video.