Hey Reader,

Over the past few years, there has been a vocal camp of people who say that lifting heavy is dangerous, and will make you slow. Specifically, the argument I most commonly see is the following:

1. Heavy lifting is typically slow
2. Doing slow things teaches your body to be slow
3. Therefore, heavy lifting makes you slow

While I recognize the concern, this argument is not substantiated by the science. In fact, lifting heavy is actually one of the most effective tools we have at our disposable for athletic development. Let me explain:

Why you (probably) should lift heavy

To understand this, we first need to introduce the topic of motor units

A motor unit is defined as a single motor neuron, and all the muscle fibers it innervates

Or in simple terms, it’s the thing your brain activates to get muscle to work (and generate force!)

Now broadly speaking, our brain can do two things in order for muscle to produce more force:

1. Recruit MORE motor units (size principle)
2. Recruit motor units more QUICKLY (rate coding)

When we achieve these things, we can use more of our muscles to produce more force very quickly!

How does lifting heavy help with this??

Heavy lifting stimulates the recruitment of MORE motor units more QUICKLY primarily thorough a mechanism known as the size principle of motor units:

The premise of this principle is simple:

1. Low force actions (like picking up a chair) require low motor unit recruitment
2. High force actions (like going for a heavy squat) require high motor unit recruitment

Per the size principle, when we lift heavy, we stimulate our nervous system to become produce more force more quickly.

And last I checked, I think we want to produce a lot of force really quickly to become more athletic

Coach's Takeaway

Lifting heavy most certainly doesn't make you slow. Its actually one the most effective tools we have for becoming quicker and more athletic

Finding ways to incorporate heavy lifting (with appropriate technique and progressions) is a critical part of athletic development.

If you got any more questions, reply to this email and let me know! And I'll personally respond with an answer

Till next time,

Casey Dashtban | Strength & Conditioning Coach