I often unfurl a large paper clip into a straight piece of wire and hold it up to a client's face. I'll then take the wire with both hands and repeatedly bend it back and forth in the same place while saying "front squat, front squat, front squat" until the paper clip finally breaks.

As my client's eyebrows start to furrow, I straighten out another paper clip, and instead of bending it back and forth in the same spot, I'll repeatedly bend one end while saying "front squat" and then bend the other end while saying "back squat." It quickly becomes clear that the second paper clip will be able to withstand much more abuse before it finally breaks.

The Lesson

Your body's structures have a limited potential to adapt, so if you chronically use the exact same exercises, your connective tissues – which are typically poorly vascularized compared to muscle tissue – will be more prone to overuse injury.

You're likely to be taken by surprise by this injury since most connective tissue has limited neural input to your brain. You won't necessarily be aware of the damage you're doing until it's too late.

Be proactive. Rotate your exercises periodically to avoid these problems. The right amount of variation will prevent broken paperclip syndrome.

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