Can a running shirt help you get a new PR?

Can a running shirt help you get a new PR?

Can a running shirt help you get a new PR?

 The Story of the Berryman Running Shirt.
In a family of runners, we are constantly doing different races and are always looking for something new. So when one of us decided to start doing ultra marathons, we all began to immerse ourselves in the sport. From participating to crewing, you really get a feel for the lengths these athletes go through to finish the race.  
After years of going to these races, we started to notice no running apparel was designed for the needs of these events. In an attempt to change the way we look at running apparel, we decided to create our own shirt specifically made for ultras. 
The overarching question was: 
Could we make a shirt that gets you closer to your next PR?