JP HARTIGAN WAS 22 when he had to pack in rugby.

He dislocated his left shoulder, and then the right one needed surgery, and after two years or so on the sidelines he returned, only for injury to hit him again.

A worn disc and a bone growth on his c5 and c6 vertebrae proved too much to come back, and the Garryowen player left his playing days behind him.

He stayed involved in the game though. A keen rugby fan, he was studying product design and technology in the University of Limerick, and his final year thesis required him to come up with a commercially viable product, and thus Shadowman was born.

Fast forward five years to 2015, and the product – designed for rugby, American football or even Aussie Rules – is being used by more than 500 college and high school football programs across the United States.

Of that, more than 50 are NCAA Division 1 schools, including last year’s National Championship runner up Oregon.

The concept, a three part tackling dummy that can simulate real game situations has most recently been picked up on a three-year deal by USA Football, the sport’s national governing body.

The idea stemmed from the frustrations of rugby training. The usual tackling aides from his experiences in were either poorly designed tackle bags or padded suits, or simply none at all.

“The issue is you have two options. You practice on dummies that are unrealistic and not true to the game, or you practice on your fellow player, and then you face injury risks on both sides.

“When I dug down deeper into the research, I saw the trends.

“There was a problem coming with the injuries and the impacts per game. Everything was on the rise in terms of the injuries and forces, and the only thing you can really do to combat that is education for players and coaches, the rules and the equipment.

“So I thought that there was a big opportunity on the equipment side. I just went at it, and built a lot of prototypes,” he says.

Shadowman allows teams to practice more tackling, and reduce injuries.

The Shadowman itself comes in three parts. There’s the dummy; a life-sized humanoid that gets inflated with both water (at the bottom) and air (at the top). The humanoid sits into an inflatable ring, which is dragged along by harness, to simulate a potential ball carrier.

With the water at the base of the humanoid ensuring it retains a low centre of gravity, it means the player can make a full-on tackle and bring the Shadowman all the way to the ground.

As Hartigan has improved the design, the product has risen in popularity on the US market.

Growth in customers year on year has been between 250 and 300 percent, with the patent on it making it the only towable and detachable dummy available.

With a limit on the number of full contact practice sessions allowed for college and high school teams, the product has allowed coaches to increase the amount of tackling training they do each day, while also reducing the number of injuries that come as a result.

“The biggest college teams in the US are using our product; the Oregon Ducks, Nebraska, Notre Dame, Virginia Tech, our list of Division 1 programs is just phenomenal.

“We’ve done some engineering to ensure that the dummy sits perfectly into the sled when you tow it, and then when you make the tackle it pops out, so that you have a full and realistic game tackle, bringing the dummy all the way to the ground.

“And then you can practice on it as a moving target, which works really well with your muscle memory, and your cognitive learning process of getting your feet, head and shoulders in the right position, and the fact that it’s made out of air and water, it allows for a lot more repetition,” he tells the42.ie.

Originally designed as a tackling dummy, Shadowman has evolved into a component used right across practice sessions.

Teams are standing it in on all types of plays; for blocking on punt returns, for passing drills or filling in for linemen, with the dummy being made suffer, and not the players.

“The cool thing about our product in American Football at the moment is that every customer we talk to has a different application for it. They’re putting it in instead of the quarterback for a scrimmage, and Shadowman is taking all the punishment.

“You see it being used in stuff you never imagined.

“It really just gives players and coaches a new opportunity to put Shadowman in harms way, and they can then get more reps and more drills, because it’s less physically draining.”

A smaller version is also used for players under 14-years-old.

With bases in San Francisco and Limerick JP splits his time between the two, while also spending time on the road in America, and frequently visiting the European manufacturer.

The past 12 months have been the most significant since he started sketching the designs more than 5 years ago.

Three full-time staff in 2014 has grown to nine full-time staff and a further 17 contracted sales representatives today, as the product’s popularity has risen dramatically.

And with rugby currently in the midst of a concussion crisis, it’s a product we could see on training pitches in the not so distant future.