It is important to continue building on the weight bearing exercises to start getting the knee used to the more compressive and shear forces that your knee will need to cope with during day to day life and your chosen sport.
You can build strength in your legs by starting to increase the resistance or weight and usually this would result in a need to reduce the repetitions. To get the body used to strength training 3-4 sets of 8-12 repetitions using a moderate weight is recommended for the first three to four weeks.
Once the body has started to adapt to these exercises, progression towards a more advanced and strenuous programme can be started. This usually involves approximately 5 tough repetitions and these would be repeated 3-5 times. When you are lifting heavier weights you are likely to experience more muscle pain and soreness after your activity known as ‘delayed onset muscle soreness’ or ‘DOMS’. Therefore more recovery time is needed between exercise sessions, so usually twice a week is sufficient when strength training with heaver weights. The national physical activity guidelines also recommend adults should aim to achieve “strengthening activities which work all the major muscle groups two days per week.”
Examples of exercises that you can use this approach with in the gym are: Leg Press and Leg Extension Machine, Hamstring Curl Machine, Squats and Deadlifts.
If you have mild to moderate pain whilst you are exercising then most of the time this is perfectly normal and nothing to worry about. You are stimulating the area in your body that is causing you some irritation so often it is inevitable that you will have some discomfort in that area whilst performing some of the exercises and this may persist for some time after finishing them. In fact the right amount of stimulation can encourage healing of tissue in the body and it does take time for you to get used to this and learn your limits. How much and how long the pain lasts for is something you will discuss with your physiotherapist, but usually if the pain and the length of the time the pain lasts for is acceptable to you, then it’s fine. The pain you may experience after the exercises does not mean you are damaging anything.
Below are some control and strengthening exercises for the legs. Regaining the muscular control is very important as this will help reduce re-injury and give you back the confidence in the knee. A good exercise to test the control and endurance is performing as many single leg sit to stands as you possibly can. Compare both legs and aim for 20-25 in one go. See video for demonstration of this exercise.