These protectors of manhood come in all shapes, sizes, materials, colors, quality, and effectiveness. They have to be safe, high quality and effective.
So what makes a groin cup "good"?
An athletic cups' shape dictates much of its ability to protect the male genitals, and it’s not just about covering your balls. At its core an athletic cup must keep the testicles from touching the sides of the cup when it gets hit. If it doesn’t then the balls that hit your groin cup causes your cup to hit your balls. Ouch. In fact, an athletic cup would be pretty useless if the testicles were pressed into it all the time.
Ok, so it covers your junk well, the testicles are not touching the sides, but what if you bend over? Or lift a leg high in the air? Where are your balls during this? If they are not inside the athletic cup it doesn’t matter that you are wearing it. A good groin cup doesn’t allow “slippage” of your prized possessions outside the cup. This is a huge deal in martial arts and other sports where leg movement is rapid and unpredictable. Baseball catchers also have this issue when squatting if the fit is incorrect.
What Holds it There
Since athletic cups are not glued in place, they have to be held there by something. There are many ways to do that, but no matter the method, as you move, the groin cup can’t. If you lift your leg high in the air, or squat, and the pelvic cup moves even slightly off your genitals, adjust it, and if you can’t, throw it away and get something else.
Size Does Matter
Cups come in many sizes, even for adults. Youth groin cups are often very inconsistent, and difficult to size since the “strap” size (as in a jockstrap) is listed only by waist size. This has nothing to do with genital size, which is largely an age issue. A 7 year old boy and a 14 year old boy should not have the same cup, but may have similar waist sizes. A good cup clearly displays an age-range or other indicator of the protection area provided.
If you have a "good" athletic cup, you may not even think about it when you get hit. And that is good!
Sports Injury Researcher, United States