My muscles are sore from playing tennis because I haven't played for quite a while.
The muscles in my arms and legs are strained/sore because I played tennis for the first time in a long time.
ーMy muscles are sore from playing tennis because I haven't played for quite a while.
「しばらくプレーしてなかったので、テニスで筋肉痛だ」
My muscles are sore で「筋肉痛です」と言えます。
for quite a while で「ずいぶん長い間」
ーThe muscles in my arms and legs are strained/sore because I played tennis for the first time in a long time.
「久ぶにりテニスをしたら腕と足の筋肉が痛い」
strained で「痛めた」
sore で「痛い」
for the first time in a long time で「久しぶりに」
ご参考まで！
カナダ 
