I guess regular use of the 600mm will give you powerful wrists ... eventually. I remember a guy in university that used to curl a 90 lb weight every day and as a result of this he was unbeatable in an harm wrestle. I recall one occasion when he had two women using both arms simultaneously and he could still hold his own. How immature! Still, this stunt served well as a chick magnet. When I used to work all summer long with a pipe wrench and manual pipe threader for the purpose of installing gas pipe to help pay for tuition my wrist and forearm were like steel. I'd shake hands with a fishing buddy and he would wince from my grip and I wasn't even aware of squeezing beyond what felt like a normal firm handshake. Those tendons really became strong. While your lens doesn't equate to a wrench, or slip-joint pliers, I'm sure that you are already stronger than you were before you got the lens. Now, what are we going to do about that allergy? We can't lose your contributions and enthusiasm to microscopic particles ... can we.
Those one-word answers can be tricky. I thought you were calling me a monster. I've been called worse.