...even if my shoulder muscle is sore. (Para. 13)
muscle: n. pieces of spring-like material in the body
In order to build his muscles he does lots of exercises every day. 为使肌肉发达起来，他每天做大量的锻炼。
After the game, all of the muscles in his arms and legs were aching. 比赛之后，他感到手臂和腿部肌肉都在胀痛。
The tennis player could hit the ball hard because his muscles were so strong. 由于网球运动员肌肉发达，所以击球力量很大。
sore: a. painful, especially from a wound or hard use
My leg is still sore from the operation. 我的腿现在还因做了手术而感到疼痛。
My muscles were sore because I had exercised too much. 我因锻炼过度而肌肉发痛。
She stayed home from school because she had a sore throat and a fever.她待在家里，没有去上课，因为她喉咙痛，还发烧。