健身練肌肉

I am not an expert, but I have several friends have injuries, here are some tips may help you.
有冇之前傷過膝頭, 之後健身train 返肌肉?
Yes, in fact many people have to deal with their injuries, or exercise while or after their injuries.

主為大 腿 前 的 四 頭 肌 及 後 腿 肌 肉, 我兩年前傷左,近排有d痛 ....e生叫我練返兩組肌肉......我係home可以點做呢????
The best way is doing exercises in the pool, water help you with the pain.

同埋每次做幾耐??? 要練幾耐先可以回復以前咁ga 狀態????
It's hard to tell, depends on your problem, try to take it easy and slow the first few weeks, if that is ok, you can increase the intensity 10% per week, don't over do it, you don't want to make it worse and stop exercise.

同埋做完係咪最好fu 冰??
You don't need to ice it, if you don't have any problem.

如果做完有d痛係咪正常呢???
Muscle pain is ok that is normal, if that is the injury pain, then you should ask your doctor to check.