Taemin talked about growing older on 'Cultwo Show' on February 25!

The DJs said to him, "You debuted when you were 16 and SHINee's already on its ninth year.  At what times do you think that you've grown older?"  

He replied, "I've been on stage for a long time, but if I don't do things like warm-up exercises, I can feel my body stiffening.  I think that's why I get frequent injuries . . . I really didn't know about [muscle] sores, but I felt [I was getting old] when the sores came."

The DJs joked, "Then it is time for us to die," making everyone laugh.