When are strength gains *not* specific?
If you enjoy this article, you will like my first book (see on Amazon).
As a rule, lifting weights causes strength gains that are very specific to the type of exercise performed in training. In other words, if we test strength using *exactly* the same set-up as we used during training, then the strength gains we measure will be greater than if we use a different set-up.
Sometimes, however, strength increases after lifting weights do not follow this rule. Instead, they are quite similar when tested in many different ways after training.
This is because the principle of specificity is a general guideline, and not a hard-and-fast rule.
But why are strength gains specific, and sometimes not specific?
Well, this happens because strength gains are not caused by a single mechanism, but by many mechanisms. Sometimes those mechanisms produce a specific effect, and sometimes they don’t.
Let’s take a look at some examples.
When untrained individuals start lifting weights, they achieve extremely fast strength gains (for many reasons).
They also achieve greater increases in muscle size than more well-trained lifters. These gains in size become slower and slower as they become more experienced.
Muscle size contributes considerably to our ability to produce force under any circumstances, whether we are lifting or lowering a weight, moving fast or slow, moving through a large range of motion or a small one, lifting a heavy weight a few times or a light weight many times, or lifting in stable or unstable environments.
So whenever someone is able to gain a lot of muscle (for any reason, but most normally because they are a beginner), then the strength gains they achieve after lifting weights will be *less specific* to the type of training they do, and will transfer to a much wider range of exercises and sporting movements.
In other words, almost any training program will “work” for almost any goal in beginners (or in other lifters who are able to gain large amounts of muscle mass for any reason), simply because of the beneficial effects of greater muscle size on all types of strength.
#2. Eccentric training
Surprisingly, eccentric training causes larger gains in maximum (lifting) strength compared to normal strength training, or even compared to strength training that only uses the lifting phase.
This is because the mechanical loading on the muscle-tendon unit is usually higher during eccentric training (because we can lower a heavier weight under control than we can lift).
In turn, this causes greater changes in the key factors that contribute to maximum (lifting) strength.
Such factors can include increased tendon stiffness, an increase in the amount of force that is transmitted laterally within the muscle, an increase in the activation of the prime mover muscles, and improvements in load-specific coordination.
#3. Long muscle lengths
When we do full range of motion exercises (like deep squats), our muscles reach a long length at the end of the lowering phase.
In contrast, when we do partial range of motion exercises (like quarter squats), the longest length that our muscles reach in the lowering phase of the exercise is still quite short.
The longest lengths that prime mover muscles reach in any exercise is usually the point they exert the most force (this is certainly true for squats). This muscle length is where muscles adapt to produce their greatest gains in strength. And this is what produces the joint angle-specific strength gains we all know about.
Yet, while partial range of motion exercises nearly *always* cause strength gains that are very specific the joint angle corresponding to the longest muscle lengths reached in training, full range of motion exercises often produce less joint angle-specific strength gains.
Why does this happen?
It happens because strength gains after training with partial range of motion exercises are caused by joint angle-specific increases in neural drive. And these neural adaptations do not transfer very well to other joint angles.
In contrast, strength gains after training with full range of motion exercises occur because of changes in regional muscle size and muscle fascicle length, which transfer better to strength at other joint angles.
What is the takeaway?
Strength gains after lifting weights are not always specific, partly because of gains in muscle size (which improves strength in almost every way), but also partly for other reasons. If we blindly apply the principle of specificity all the time without understanding the mechanisms by which specific strength gains happen, we will not achieve optimal results.
Also, there are circumstances in which people (most normally when they are beginners, but ultimately for any reason) might lift weights in a specific way, yet still gain strength in non-specific ways. This can happen whenever they gain large amounts of muscle mass. Using the same program as an advanced lifter as you did as a beginner (or as other people who have extraordinary muscle-gaining abilities) will not work as well as you might hope.
If you enjoyed this article, you will like my first book (see on Amazon).