I’m dying.



This is it, the end. I’m sure of it now. Through the blobs of sweat on my glasses, I can see a strange white light in the distance, and if my thighs and lungs weren’t on the verge of bursting into flames, I’d be running straight toward it. Anything to end the agony.



I’m working out in a small, nondescript South Loop gym with Ian Mack, the performance coach and movement expert — “body nerd” is his self-assigned descriptor — who helped Patrick Kane have the best season of his career at age 30.



There are a handful of professional athletes here on a Wednesday afternoon, decompressing after their own hours-long workout, including the Devils’ Connor Carrick, the Avalanche’s J.T. Compher, and free agent Riley Sheahan. I’m almost certain they’re laughing at me.



Oh, wait, that’s because they are.



By this point, I’ve lunge-walked, barefoot, back and...