Tennis Players Have Asymmetric Butt

Today, people, we are going to study butt. Some very athletic butts.
We have probably seen athletes with two distinct limb sizes, for example Rafael Nadal with his enormous left arm and skinny right arm.

Image: itsmysports.blogspot.com

So if this phenomenon occurs in arms, does it apply to our thighs, and subsequently our butt? After all, football players do have a favorite foot.

Sanchis-Moysi et al. "Iliopsoas and Gluteal Muscles Are Asymmetric in Tennis Players but Not in Soccer Players" PLoS ONE, 2011.--scientopia.org

Apparently someone has done research on this and came up with the result: tennis players do have asymmetric butt.
To explain this we have to take a look at the anatomy of our butt.

Image: wikipedia.org

The gluteal muscle group is on the back side, and contained three muscles, the gluteus minimus, the gluteus medius, and the gluteus maximus. These all begin on the back side of the pelvis. The gluteus minimus and medius connect at the top of the thigh, while the gluteus maximus wraps around about halfway to connect on the side. And the gluteus maximus "forms the prominence of the buttock".

Image: picturesdepot.com

So the researchers recruited some football players (from some LA Liga teams), some tennis players (international tennis federation), and some nerds to stick their butt in an MRI. The images of the muscles constituting the butt is studied and compared. Surprisingly, the football players fare quite well compared to the tennis players.

Image: blog.reelloop.com

The soccer players had right and left side hypertrophy (overdeveloped muscles) of 32 and 35%, or roughly equal, while the tennis players showed hypertrophy of 24 and 36%, which means the non-dominant side was actually BIGGER than the dominant side.

For the gluteal muscles, the soccer players actually showed no hypertrophy compared to normal controls, while the tennis players showed aymmetrical hypertrophy similar to the iliopsoas group, with the gluteal muscles on the non-dominant side 20% bigger than those on the dominant side.--scientopia.org

Image: blog.reelloop.com

The researchers reason that football players do all lot of running apart from kicking, and that helps to compensate and result in more symmetry. Tennis players, on the other hand, do a lot of short burst, sudden stop, thus resulting in more reps of the dominant side.

So, the next time you watch a tennis match, please treasure the opportunity to observe science at work. XD



Malcolm

info: http://scientopia.org/blogs/scicurious/2011/08/05/friday-weird-science-for-a-highly-symmetrical-butt-you-might-want-to-consider-soccer-instead-of-tennis/