How much rehabilitation is enough after anterior cruciate ligament (ACL) injury?

You’ve ruptured your ACL, had surgery (or extensive conservative therapy) and gone through a heap of hard rehabilitation. How do you know if you’re ready to get back sport and activities? It’s a question that clinicians face every day.

What do we use to judge and when we decide, how do we measure it?

Maybe we think that strength is important. As I so often highlight, strength is important, BUT so is the:

  • speed of muscle activation,
  • the patterning of activation
  • and your ability to cope with unpredictable, rapid joint loading


What does that mean? Well, injuries happen very quickly;

An ACL injury typically occurs in less time than it takes to blink an eye!

So it’s important that you do the right sort of rehabilitation to make your muscles activate quickly and produce force rapidly so when you do get back to sport on the field/court/slope/pitch etc. you’re better able to protect yourself from further injury. Incidentally, this type of exercise is different to exercise that develops strength.
I came across this article the other day, which summarises really well the challenges of ACL rehabilitation and the risks and incidence of re-injury

So many things need to be taken in to consideration and every individual will be different in their rate of progression and unfortunately there’s no definitive criteria to determine whether or not you’re ready. However, a pre-planned, structured programme of ‘end-stage’ rehabilitation that incorporates sport-specific and graded exercises is ultimately the best approach to guide your safe return to sport.

Certainly towards the end of your rehabilitation, you should be doing dynamic exercise that involves rapid twisting, turning, leaping and bounding and activities that replicate some of the stresses you’ll encounter when you do get back to sport. And these should be graded.

[Here you can find out exactly what to do and how!]

What do I mean by graded?

For example, if you play rugby or football, you should make sure that you progress from doing agility exercise inside wearing trainers, to outside on the field wearing your boots. The studs enable you to grip the grass when you turn suddenly but in doing so additional rotational forces are placed on the knee that you need to be able to deal with without thinking.

The difficulty of the exercise is graded – first you (and your muscles!) need to learn how to twist and turn properly inside where the environment is controlled and ‘safe’, going from slow to fast, non-injured leg to injured leg. Then, when you’ve mastered this you increase the difficulty of the task by changing our footwear (boots) and surface (grass) taking care to start slowly again and build it up.

So how much is enough?



As I said, unfortunately there’s no hard and fast rules on this, BUT as a guide, the earliest return to sport after ACL reconstruction if you’ve followed a comprehensive rehabilitation programme is around 6-months post-surgery. If you don’t have this luxury and find yourself having to ‘do your own thing’, it might take 9 or even 12-months.

The key is getting the right information

Read more on ACL injury, return to sport and rehabilitation here and here.