As a trainer, I’m always looking for trends of what works and what doesn’t work. One of the trends that absolutely does not work is holding your breathe while working. One day, I almost had someone pass out on me because they decided breathing while lifting wasn’t cool. You need to breathe. Consistently breathing on each rep is necessary for performing at full strength and explosiveness. During a bicep curl, on the way up as you’re actually doing the curl, you should be exhaling. On the way back down, you should be inhaling. It’s simple, but people forget to do it. Just breathe man!