Two are for show. Two are for go.
When it comes to working out the thighs, a lot of people only train the showiest muscles: the front and back, the quadriceps and the hamstrings. These are the ones that draw admiring glances if they bulge (for guys) or curve (for girls).
And while those two muscle groups are important in terms of function, there are two other muscles that are just as important to train and to make strong. They're the muscles that can literally save your butt if you're in a spot where you need them. One is the adductors, which are on the inside of the thigh. They allow you to squeeze your legs together. The others are the abductors, which move the legs apart.
The names of the two muscles can be confusing because there is only one letter that differentiates them. But here's a trick to remembering the correct name for each muscle. The word "adduction" means moving a body part toward the center of the body, as in holding the legs together. The word "abduction" means moving a body part away from the body, as in spreading the legs. To remember the name of the muscles on the outside of the thigh, think of the word "abduct," which means to take something away.
In addition, if you are using machines to work these muscles, the abduction machine is the one that people giggle about because it's used by spreading the legs against resistance.
Here are situations where you need both muscles to be strong: Suppose you are running on a slippery surface, such as grass or a wet sidewalk, and your foot starts to slide out. If your adductor is weak, you may not be able to stop the slide, and you can end up with a nasty groin pull. Or you may be climbing boulders or a flight of stairs and lose your balance. If your abductors are strong, you can take a step outward with one leg and regain your equilibrium, thus preventing a bad fall.
Building functional strength in these muscles is easy. You don't even need to go to the gym. A stretchy exercise or resistance band will do the trick, or even a length of rubber tubing.
An exercise band comes in a circle, but the rubber tubing will have to be tied into a circle at each end. The tubing will provide more resistance than most exercise bands. Put one end of the band or one circle of the tubing over a hard-to-move piece of furniture, such as a sturdy table leg or the leg of a bed or couch. Slip your foot into the other end.
Take a few steps away, so that the band is stretched. Keeping the free foot still, stretch the banded leg out and away from the body. To increase the resistance, just take an additional step away from the fastened end of the band. This will work your abductors. Do between 10 and 15 reps.
Next, turn around and stretch the banded leg across your body, so that it moves past the middle of your body and out to the other side. Again, do between 10 and 15 reps. If you feel any pain or pulling in your groin, the resistance is too high. Lower it by taking a step or two inward to where the other end of the band is fastened.
You won't be able to build big showy bulges by working these muscles. But by working them consistently, you definitely will be able to prevent what could otherwise end up as a strain, a sprain or worse.