I was too out of shape to catch him
Why would you say you were too out of shape?
When I was catching him I felt the pain when I breathed
If you are having trouble keeping up with others, then you might need to exercise more.  Try to go to the gym, or run more in your own time, and you should build up more speed and stamina.  You will be healthier and live a better life overall.
Exercise? Wooah that sounds like a lot of work.
It's a lot of work, but it's the best way to get in shape quick. And you'll body will feel great!