It is afraid that the middle-aged and elderly people themselves are very favorite, that their legs and feet to give back the power to participate in the study, a moment of happiness, forget their age, 'improvisation' performance, in the many applause, forget their age, the knee cartilage is very easy to be injured! Once injured, it is difficult to heal, even the general square drill, square dance can not be jumped, then regret is also too late.
Middle-aged and elderly people still need to 'live within their means' is good.