Nish Nadaraja made a quick lunge for the ball. Mr. Nadaraja said he felt his feet tangle and he fell to the pavement. He wanted to make a play with his paddle and braced himself.

Nope, that's right. He said he faced-planted.

Mr. Nadaraja played through the pain, even though his wife thought he should have taken a break. He admitted that he needed antibiotics.

It was a wound stemming from a national sensation that shares a name with a snack or a sandwich topping, but that is proving to be more dangerous than advertised. As a flock of middle-aged players migrate from tennis or start fresh with an easy to learn sport, the aches are bucking the game's low impact reputation.

Injuries to the ball were on the rise before the outbreak of the swine flu. According to an analysis published in The Journal of Emergency Medicine, 90 percent of pickleball injuries were to people over the age of 50.

Part Ping-Pong involves hitting a sphere with a paddle over a net. The game is played in a small space and requires little running. The Kitchen is located near the net. Something could go wrong.

Noe Sariban is a former pro player and physical therapist who markets himself as the Pickleball Doctor. The name of the disease is tennis elbow and it is now called pickleball elbow.

Pickleball sounds like a silly game but is actually a sport. The ball is not a bocce ball.

Nish Nadaraja, an entrepreneur in Northern California, recently face-planted during a pickleball match.Credit...Christie Hemm Klok for The New York Times

An analysis of emergency-room visits related to pickleball was published last year. The study found that 85 percent of the visits were to people over the age of 60. The most common injuries were broken bones.

The number of emergency-room visits related to pickleball by people 60 and older was equal to the number of tennis visits. The average age of players is 38, but half of them are 55 years old or older, according to the governing body. Older bodies are more likely to have strains that are easy to amplify.

It is not easy at any age. It involves quick stops and starts and a lot of twisting. On a small court, players tend to reach or bend to make a play that is harder on the body than it looks. In tennis, a new player might not think to chase down a ball, whereas in pickleball, the temptation is greater to bend, reach, and charge.

The 53-year-old patient was in pain when he lifted his arm over his head. When he worked for the Los Angeles Dodgers and the California Angels, Dr.Roth treated cases caused by tennis and swimming, as well as injuries from pickleball.

The doctor said that you are not just hitting the ball. The players are working on the long muscles of their legs.

Slips are caused by stops and starts. The largest share of emergency-room injuries were in the category of Slip/Trip/Fall/Dive.

Injuries can include “Achilles’ strains or tears, shoulder problems, rotator cuff injuries, lower back problems such as disc injuries, muscle strains,” Noe Sariban, a pickleball instructor, said.Credit...Christie Hemm Klok for The New York Times

Amy Fenoglio, a hand and upper-extremity surgeon at the University of Colorado, said that most of it is from tripping.

The kitchen is next. The nonvolley zone is a seven foot strip in front of the net on the other side. The court is 44 feet long and 20 feet wide. A player is not allowed to step foot in the Kitchen, so when a ball heads there, a player may bend forward to return a "dink," a shot that hops over the net and lands in the opponent's Kitchen.

The risks are familiar to Mr. Sariban. A former junior college basketball player, he was in a small professional pickleball tournament in January of last year and found himself at the edge of the kitchen.

He said he has hit a million volleys. I felt my back lock up when I hit the ball, and in my head, I said, 'Huh?' He had to lay down on the court. He said that he could barely walk and that his wife had to help him get into the passenger well. He had back problems. He thought he wouldn't play a sport again in his life.

Warming up without a paddle is one of the things Mr. Sariban teaches his players at his clinics. He said it was amazing how no one warmed up. It's the same thing everywhere I've taught. They don't warming up.

The risk of injury isn't higher than in other sports but the perception of risk is lower. Death-hards like Debbie Landa say that the risks should not discourage participation. She said an older woman in Palm Springs inspired her daily.

Ms. Landa has had various issues with the sport. She said that the nasty players are the real pains.

They have to loosen up. She said, 'You're playing a game called pickleball!'