Should a client perform a squat exercise if the squatting motion hurts, for example, the client's knee?
Well, some people might argue that if the pain is mild, then squatting is ok. But, generally, if it hurts to squat, squatting is probably not such a good idea.
Unless you know the client's Load Tolerance.
What's Load Tolerance? Load Tolerance (LT) is a testing procedure I created to find the maximum amount of pain-free force a person can produce for a given movement without a break in form*.
That may sound familiar to you. It sounds a lot like the definition of a 1 Repetition Maximum (1RM) from the world of athletic training and fitness. 1RM is the maximum amount of weight a person can lift or move through a defined range of motion one time.
So how is Load Tolerance different from 1RM? Load Tolerance includes the entire gravity spectrum from less than body weight to above body weight and is typically 5-10 repetitions. 1RM is traditionally limited to above body weight loads and is one repetition.
Trainers and athletes often use the data from the 1 RM test(s) to define the upper limit of training and to determine training loads. For example, strength training is often performed at 85% of 1RM. So, if your squat 1RM is 250lbs., your training load would be around 212 lbs. (this varies based on the intent of training, the rep range, etc.). I, and other similarly trained therapists and trainers, use the data of a LT test(s) for the same basic purpose: to idenitfy physical upper limits and determine trainning loads. The difference is in how we use it.
1RM data is used to determine muscle training loads only. LT test data is used to determine all joint tissue training loads: muscle, tendon, cartilage, muscle.
At this point, some people start scratching their heads. Are you saying that you can train tendon? That you do that somehow or in some way differently than muscle? Yes. Think of it this way. Normally, a healthy tendon is somewhere around 2 times stronger than its associated muscle which makes complete sense*. About the last thing you would want is an arrangement where the tendon is weaker than the muscle. Of course, this is exactly what happens in the case of tendonitis and tendonosis. The tendon is now less capable of withstanding the tension created by the contracting muscle. The result? You hurt.
So, let's take an example. Let's go back to the squat. Your client's knee hurts over the patellar tendon and let's assume she has patellar tendonosis. She tries to perform a single leg squat but can't. It hurts. So, you now also cannot (or at least shouldn't) prescribe any muscle strengthening squatting drills since the force would exceed the client's tolerance. What do you do? You could wait. Just skip the drills and wait for the tissue to become less irritable and the try the drill again in 10 to 14 days. But, what happens if, after 10 days, you get the same result?
This is when practitioners start soft tissue techniques: myofascial release, massage, Graston, etc., to relieve the pain; to have something to do until the client can tolerate the drill. Or, concerns about biomechanics become primary. Sometimes abnormal biomechanics are a source of overload. Nothing wrong with that either. But, the problem is that drills are often aimed at muscle when the faulty tissue is tendon. Why not find the LT for the squatting drill, dose it for tendon, and not only relieve pain but improve the tensile quality of the tissue?
To accept my argument, you have to accept the premise that 1.) tendons respond both positively and negatively to physical stress 2.) that the stress required for healing is different than that required for muscle 3.) that you can actually do it.
But, that's coming. I'll go over all three arguments in the next few posts. My point in this post is to raise awareness around the concept of Load Tolerance Testing; to think of the tissue that's injured, find the LT for a movement that involves that tissue and then design drills using that data. I'll explain how to do that with selected tests in future posts.
DK
*
Kelsey, D. D. and
E. Tyson (1994). "A new method of training for the lower extremity
using unloading." J Orthop Sports Phys Ther 19(4): 218-23.
Elliott, D. H. (1967). "The biomechanical properties of tendon in relation to muscular strength." Ann Phys Med 9(1): 1-7.
