After an ACL injury or ACL surgery, many athletes report experiencing increased frequency of muscle cramping. Oftentimes, this cramping occurs in the toes, calf, or hamstring. It’s important to note that this is a normal part of the process and that a cramping sensation isn’t necessarily a bad thing. So why does it happen?
Let’s start with an analogy that athletes may be able to relate to in order to set the scene.
Your favorite (American) football team suddenly develops offensive line problems. Every time the quarterback drops back to pass, he only has a second or two before a defensive lineman is on top of him, hitting him harder and harder every snap.
Before, when the offensive line was playing well, the quarterback was able to stay in rhythm. He could take his time, go through his progressions, and find the open receiver.
But now that the offensive line was leaking like a sieve, he looked like a totally different quarterback. His feet sped up, he was panicky, and even when the offensive line did give him a little bit of time, he was getting the ball out as fast as humanly possible.
The result? A less effective offense, more passes thrown away, and more interceptions.
The quarterback had experienced the trauma of being hit repeatedly, lost trust in his offensive line, and it was causing him to be much more sensitive to the pass rush, which ultimately affected his performance. In order to gain back the quarterback’s trust, the offensive line will have to consistently show it can protect him.
A similar sequence of events occurs after an ACL injury and/or after ACL surgery.
The second the ACL tears, the nervous system recognizes the body has experienced a severe trauma. It loses trust that the athlete can perform movements that would cause the knee joint to be stressed. In turn, the nervous system becomes much more sensitive to various loads placed on the knee.
The result? It “locks down” muscles responsible for generating forces around the knee joint by rapidly shortening the muscle… what we know as cramps.
It does so via the following mechanisms:
There are neuromuscular sensors in each muscle that control two things:
- How much load the nervous system is willing to allow the muscle to take on
- How long the nervous system is willing to allow the muscle to get
As noted earlier, after an ACL injury and/or surgery, the tuning on these sensors become highly sensitive. They no longer allow the muscles to take on as much load or as much length. If the sensors determine length or load are beyond their limits, they send an alert signal, which locks the muscle down with a cramp.
Similar to the quarterback and offensive line, in order to gain back the trust of the nervous system, the muscles will have to consistently show they can properly support the knee. This is one of the crucial roles of performing exercises without compensation in the ACL recovery process.
In a sense, the cramps that athletes experience during the ACL recovery process are a good thing. It means you are challenging the nervous system by loading the muscles and forcing it to reassess its tuning parameters. The more frequently you do it, the more success you will have retuning those neuromuscular sensors, allowing you to continue pushing the recovery process and ensuring muscles are properly activated before return to sport.
If you’re interested in working with me and my team to build quad strength quickly and avoid atrophy after ACL surgery, click the link below to find out if you qualify for a 2 day trial.