Why the Triple Hop test isn’t always a good barometer for ACL rehabilitation

Posted on November 16, 2018

(Last Updated On: November 16, 2018)

The Triple Hop test is a popular tool in the ACL rehab world as an indicator for how well the surgically repaired leg matches up to the non.

In theory it makes sense. If the surgically repaired leg can perform as well as the non in a jump test, you have a good indication rehab has been effective / is over / is on track.

However, symmetry, particularly in athletes, is commensurate with trying to find an honest politician: Good luck.

Specifically regarding jumping: If you watch enough athletes, or have been around enough, you’ll eventually notice patterns when it comes to jumping. You’ll also notice patterns with limb strength. (Limb strength applies to the general population as well.)

Those patterns are:


-Athlete predominantly jumps off two feet

After the first dunk, notice how Spud Webb jumps on every following jump. Also notice how much more he can do off two feet compared to one foot.


-Athlete predominantly jumps off one foot


Opposite leg dominance

When the athlete predominantly jumps off one foot, they just about always prefer to jump off the leg opposite of their hand dominance. LeBron James = Right Handed = Almost always jumps off his left leg.

-> More about Lebron’s vertical jump ability

Nearly all people: Right handed = left leg stronger. This is even more pronounced in athletes. That is, take Computer Dude, have him throw a ball as far as he can with both arms. His dominant hand will throw further. But, take a MLB pitcher and not only will his dominant arm throw further, the discrepancy will be much greater than Computer Dude. (Computer Dude maybe has 10% difference but MLB pitcher has 40% (note: I’m making up numbers for illustration.))

Or take someone with a basketball history. Chances are they are way more proficient going one direction (their right) than the other. Going one direction more than the other, like using your right hand more for lay-ups, lends itself to jumping off one foot more than the other (the left).

ACL rehab

Or someone with a long jump history. Thousands of jumps on one leg are going to make you better jumping off that leg than the other. There is a reason you don’t see long jumpers at the Olympics switching legs each jump.


Coming back to the Three Hop test: Say you’re someone with an athletic history along the above. Let’s say you are a left footed jumper. Next, say you tore your right ACL.

BEFORE you tore your ACL, do you really think you could ever jump as far on your right leg as you could your left?

Probably not.

So post-ACL reconstruction why are you even bothering trying to even out something that you’ll never even out? Something that was never even to begin with?

If your right handed and broke your left arm, after you got your cast off you wouldn’t think “I need to make my left arm as strong as my right.”

It’s not necessary, and it’s self-defeating. “Ugh, I’m still so far away from being normal.” You need to acknowledge what normal is for YOU.

In fact, here is an interesting study I found done by people looking at rehabilitating the neurological abilities of the feet. Abstract:

“If footedness is defined in terms of a reliable role differentiation of the two feet and legs, right-handers show a right-foot bias for activities requiring fine manipulation and focused attention. (Note from me: Think of kicking a ball. If you’re right handed, you likely feel way more confident in your accuracy with your right foot.)

In adult right-handers, the left leg tends to be the longer and heavier one, in keeping with the support role of that leg.

In left-handers, anatomical asymmetries tend to be in the opposite direction, and functional preferences are somewhat less clearly expressed. Foot biases and their interaction with hand biases are of practical importance in the design of man-machine systems. The considerable sensitivity of foot and leg performance to neurological insult renders the assessment of foot and leg use very attractive for purposes of clinical neuropsychology”

Source: Asymmetries in Foot Preference and Skill and Neuropsychological Assessment of Foot Movement

Here’s another way of putting this: For some people coming off ACL surgery, expecting symmetry in a Three Hop test is like expecting symmetry from a pitcher in velocity between arms. There is just no way Justin Verlander is EVER going to throw as hard with his left arm as he does with his right. In fact, for him, trying to do so would be counterproductive.

If you’re having issues with the Three Hop test reevaluate whether it’s even worth it for you.

For an anecdotal perspective, I was just fully cleared from my own ACL rehabilitation and I didn’t once bother with the three hop test. I tore my right ACL; I’ve been jumping off my left leg for 20 some odd years…Why bother with a test I know I’ll never satisfy?

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