Researchers say those folks who bug you at the gym by grunting or cursing might be getting more out of their workouts than you are.

In recent years, a number of bodybuilders have been kicked out of gyms, especially at Planet Fitness locations.

Their crime?

Grunting too loudly while lifting.

But new studies show that grunting might be critical to reaching peak performance — and perhaps that behavior should be taken even a step further.

A growing body of research also indicated that cursing while exercising can boost physical performance.

People who swore while riding an exercise bike or squeezing a handgrip generated more power than people who repeated a neutral word during the same exercises, according to one new study.

Richard Stephens, PhD, a psychologist at Keele University in England, presented the results of that study at a conference last month, spurring an explosion of media coverage on how swearing makes you stronger.

Read more: What exercises are the best? »

These findings aren’t news to everybody.

“When I’m chugging up a hill on my bike, I’ll often use a common four syllable curse word invoking a mother,” said Dave Bexfield, founder of the website ActiveMSers, which seeks to inspire those with multiple sclerosis to stay active.

The 48-year-old Albuquerque, N.M., resident told Healthline he accidentally discovered this cursing trick for helping with cadence while biking, but he also uses it to “get over that hump” to push past 90 percent effort during high intensity interval training.

That lines up with Stephens’ findings.

Stephens asked study participants to choose a swear word and repeat it while performing the exercises.

Those who cursed reportedly hit a peak power two to four times higher than those who didn’t during the half-minute stationary cycling trial.

In the grip test, the cursers squeezed 8 percent harder.

The full paper on the studies is currently under peer review and has not yet been published, Stephens told Healthline.

Read more: How long does it take to get in shape? »

No matter the benefits, cursing repeatedly and purposefully at the gym or spin class isn’t exactly encouraged — yet.

Nonetheless, if you can get away with it at your gym, grunting has also been shown to boost performance.

Dennis O’Connell, PhD, DPT, a physical therapy professor at Hardin-Simmons University in Texas, has found grunting during a tennis serve can boost the power by 4.5 to 5.5 mph, and that grunting can increase isometric force while pushing or pulling by 10 to 20 percent.

The sex of the participants made no difference in his studies, nor did whether the participants were already grunters or liked grunting.

“It continues to surprise the heck out of me that we keep finding the same thing,” O’Connell told Healthline.

He has done three tennis-related studies, all with different investigators and subjects, although an earlier study on whether grunting aids in deadlifting a barbell didn’t find a significant difference.

“It may be task-specific, may have to involve movement,” O’Connell explained.

Other studies have shown grunting can boost force in a karate kick and other activities.

O’Connell wasn’t aware of the findings on cursing. He noted the exercise strategy may have its limitations.

“People thought grunting was obnoxious, so I can only think what they would think of people cursing,” he said.

Read more: It can take just two weeks to get out of shape »

Bexfield sometimes opts for grunting, but he says it doesn’t compare to the boost from cursing.

“As a rule of thumb, I try to avoid screaming out obscenities in the gym. If I’m lifting, I’ll grunt just like anyone else,” he said. “That said, when it comes to motivation, I can’t grunt my way to peak performance. But I sure as hell can try to curse my way there.”

How either works to boost performance is still a bit unclear.

In the case of grunting, O’Connell thinks the act of taking in a deep breath and momentarily holding it in order to grunt may act like a sort of Valsalva maneuver, in which exhalation is attempted against a closed airway. That tends to stabilize the spine and core.

“This gives you a great platform for doing a task with your arms and generating force,” says O’Connell.

Stephens’ work on swearing has shown it likely increases pain tolerance. He also has theorized that, whether you do it out of an emotional impulse or choose to do so deliberately, cursing ups emotion and releases adrenaline.

He has also theorized that the performance boost of cursing might wear off if the words become less taboo.

But were those bad words too off-limits, his research might never have gotten off the ground.

“We were probably quite lucky in the timing of our research on swearing and pain,” he wrote in 2013. “Maybe a few years earlier and it would still have been too much of a taboo topic to secure peer review publication.”