always me!!!!!!!!!

[birdo1]

can someone tell me whats happening please.im trying to do an excersise (standing up and pushing the dumbells in the air alternately)but when i try to start the right arm seems stiff and will only push it after some pain then i can do ten easy.but its always that first one to start it that kills.its my tricep i think.its almost like its saying im not pushing it.and wen i have done ten and put the weight down my arms grip the bar and dont wana let go because if i do i get a pain in my forearms and tricep.im lifting 140 pounds on 2 dumbells at the moment.70 pounds each.any ideas?

[rabbit_punch]

happens to me sometimes, i don't have a clue what it is.

[jbrowncbr]

what are you talking about? "(standing up and pushing the dumbells in the air alternately)" are you talking about a standing alternating dumbbell shoulder press?