Poles providing a good workout.....

I was recently talking to a mate, who swears by his Gardiner poles as producing the best cleaning results. He also said his longer sized poles, namely the carbon fibre ones 38' and 56' ones respectively give him the chance for a good workout, and to build some muscles on the old arms. Never really thought about it, until he mentioned but thinking back to when I first started out I had these really skinny arms, now my arms are bigger and the best thing is I've never had to go to the gym to achieve this. It was solely achieved by me being out and about using me poles. So my questions to you kind readers is what poles do you use? Are they lightweight or heavy ones? And have you noticed any increase in muscle mass?