Boys will be boys. 2PM's Taecyeon is learning the hard way that fun and games can lead to pain.

Taecyeon reportedly injured his humerus bone -- the bone stretching from one's shoulder to elbow -- while arm wrestling his fellow groupmates.

JYP Entertainment reported the news on the official homepage, "After finishing promotions in Japan on May 15th, Taecyeon injured his left humerus while arm wrestling with the other 2PM members. He went to the hospital right away late at night, where he received his diagnosis, inspection, and treatment in the emergency room. Today after his arrival in the afternoon, he's currently in the middle of getting a more detailed inspection at the hospital. According to the results from the hospital, it seems it's easier to injure or fracture bones while arm wrestling when one's arm muscles are big from working out.
There are similar cases that pop up every year at the hospital.
Taecyeon is undergoing all the necessary measures so we'll update you as more solid diagnosis becomes available."

For those waiting for Taecyeon's return, his schedule is pending on his doctor's final say.