Knee Strengthening Exercises


As someone who quickly recovered from a full house of complete ACL, MCL and LCL tears, I understand the importance of knee strengthening exercises ahead of ACL reconstruction surgery to enabling a rapid recovery after ACL surgery.

In my own case, I was able to start knee strengthening exercises 10 days after my injury occurred. Even before focused knee exercises can begin, there are several things that need to be done:

  • Follow the advice of your surgeon and use RICE techniques (rest, ice, compression, elevation)
  • Accelerate the ice and compression with a good product such as the Aircast Cryo/Cuff Cooler
  • Avoid pain. You’ll be prescribed strong painkillers but it is really important you take them as prescribed including during the night. Set your alarm – don’t let the pain get you otherwise it can be difficult to get rid of it and, more importantly, you won’t want to move and moving is critical. You need to gain range of motion in the knee ahead of surgery and you need to reduce swelling to enable surgery
  • Twenty to thirty years ago, ACL injury patients were effectively immobilized before surgery. This old school thinking has been superceded by “movement is good.” Today, medical science believes that establishing range of motion is important as is exercising the calf muscle which, in turn, will reduce atrophy (muscle wasting) and control swelling. Walking is good but only if supported by a good brace such as the DonJoy TROM Adjuster Knee Brace. Becoming mobile allowed me to start driving again 8 days after suffering my ACL tear.

The following are the knee strengthening exercises I performed as part of my recovery together with the timescales of when I was able to perform the exercises:

Day 12 (Pre-ACL Surgery Knee Exercises)

My first physical therapy session with Larry Meyer at the Boulder Center for Sports Medicine. He’s immediately concerned about the swelling in my ankle and knee and he puts a compression bandage on my lower leg.

The first three exercises he gives me are ankle pumps, heel slides and quad sets and these turn out to be the foundation of pre-surgery knee strengthening exercises.

  • Ankle pumps – lie on your back with your leg elevated (e.g. lie on the sofa with your foot on the arm of the sofa) and flex your ankle backwards and forwards (i.e. push your foot away and then back towards you). This works the calf muscle to prevent atrophy and reduces swelling
  • Heel slides – lie on your back with the heel of your injured leg on a smooth surface. Ideally you would have your leg elevated but if you’re at home this may not be practicable. Slide your heel towards your bum, thereby raising and bending your knee. This is an essential exercise in re-establishing range of motion
  • Quad sets are really tough after 10 days of inactivity and damage. Start by focusing on your good knee. send a message from the brain to your quad muscle and see it respond. Now try on your injured knee. Nothing? No reaction at all would be totally normal but you need to work at getting your quad muscle to fire again. There’s no secret to how to do this, more a case of mind over matter! You need to do this as the muscle needs to fire before you can strengthen it and strengthening it is key to strengthening the knee and being able to straighten the leg.

Larry tells me that Dr McCarty is unlikely to operate unless I can get my knee to bend to 90 degrees buy my current knee bend is only 60 degrees.

Day 16 (Pre-ACL Surgery Goals)

Back to see Dr Eric McCarty. Bad news, Larry’s 90 degrees is now Eric’s 120 degrees. I’ve spent the weekend doing knee strengthening exercises in preparation for my second physio session – with Mark Shepard. Mark works hard manipulating the knee – actually moving my knee cap and working the muscles around it and it feels odd that something so injured can be manipulated so much.

Quad sets now occur on a rolled towel and after half an hour of Mark manipulating my knee it was time for the knee bend protractor to come out….94 degrees! According to Mark it becomes much easier after I can get to 105 degrees at which point I can probably get on a stationary bike and the last 15 degrees should come easily.

Day 19

Third physio session. Larry’s pleased that the swelling has gone down (RICE and a compress bandage) and works on my range of movement. The protractor shows 107 degrees! All the hard work at home is starting to pay off. I haven’t missed an opportunity to work through the range of knee strengthening and flexibility exercises. 13 degrees from surgery.

Day 23 (Using a Stationary Bike)

Fourth physio session. The weekend just gone was hard. I’m finding it really difficult to repeat the range of motion I attain in physio when I’m working at home on my own.

My frustration eases as the protractor shows 111 degrees and Mark suggests I get on the bike! I think back to when he said it was much easier once you got knee bend past 105 degrees and you could get on the stationary bike…

Pedalling was tough. I spent 5 or 10 minutes just rocking back and forwards in half circles before I was finally able to get my knee to go full circle backwards. A few more turns later I was able to get my knee to go full circle forwards. It was painful (mainly the MCL) but a few turns later the pain subsided and I became just about the slowest cyclist in history.

The homework assignment was to cycle at least twice a day for as long as I could manage each time.

Day 27

Physio session #5 and one week (not to mention 9 degrees) from surgery.

No bike in this session but I’m introduced to the gravity machine which uses gravity to help bend my knee. This actually feels good and I urge Mark to bring his protractor and see how far I can go – the first measure is 112 degrees but I know I can do more and manage to get to 114 degrees – 6 degrees from surgery.

In little ways I’ve managed to measure some kind of progress every day. This is mentally important and, I feel, a key secret to rapid ACL recovery.

Day 32

I’ve done well sticking at my workout regime over the past 5 days but today is my last physio session before surgery.

I start out again on the bike and spend 5 minutes or so of painless cycling. Then I move onto the gravity machine. The first measurement has me at 115 degrees so Mark moves me to the physio bench and works his magic massaging the knee. After 10 minutes or so we go for the final measure….119 degrees! Of course, I couldn’t stop there. It might only be 1 degree but it’s failure to me and to fail now, so early in my rehab, is unacceptable. I go for one more measure. He bends my knee into position and coaxes my knee into further bending. The protractor comes out again, my knee feels as if it’s going to burst and the result is…124 degrees!! I made it, I’m ready for surgery!