Not all muscles are created equal, and sometimes, there’s nothing you can do to make yours like those of the person next you crushing bicep curls. This is the case in terms of long versus short. But what’s the difference between long muscles versus short muscles, and how does it affect your workout? Learn more before your next trip to the gym.

Who Has What

Most people are simply born with long or short muscles: “A muscle is attached to bones via tendons. If the total distance from one bone attachment to the other bone attachment is ten inches, then the entire muscle plus tendon structure needs to be ten inches. The length is determined by where the bone attachments are,” explains Marilyn McAllister M.S., of YourFitnessYourLife.com.

However, McAllister explains that muscles can become shorter or longer for short periods of time if you’re stretching (longer) or sitting at a desk all day (shorter).

The Benefits of Long vs. Short

Muscle Man Pulling a RopeThe benefits of long versus short muscles differ from person to person: each muscle type looks different, so if you want to have muscles with more peak you’ll prefer short muscles, as opposed to long ones, which run further from point to point.

To quickly assess which camp you fall in take a look at your muscle when contracted and supinated (not flexed). In biceps, for example, your arms will look bigger when supinated, but the muscle will be small in height when contracted, or flexed. The reverse is true for short muscles.

How Length Effects Tightness

Your muscles are like an elastic band, and they stretch and contract depending on the movement you’re performing. This movement comes from your joints, which pulls the muscles in various directions. This can cause your muscles to lengthen and shorten.

“Sometimes an imbalance occurs and one set of muscles is pulling harder, thus is shorter than the opposing muscles. Those opposing muscles are now too long and have the job of resisting the increased pull of the shortened muscles.  It is this increased tension that causes the muscle to be painful,” says Jen Flemming, a certified massage therapist. In this case, muscles can temporarily change to long or short, not permanently however.

Having long or short muscles doesn’t affect much other than the way your muscles look when flexed. Learn to love your muscles and choose workouts to maximize yours specifically.