im confused, are you only supposed to do isometric stretching after doing some type of weight training for legs ? i workout legs twice a week at the gym squats/deads what if i want to do isometrics 3-4 times a week?
I do isometrics at least 3x/week, so you shouldn't have a problem there. There's no real rule for what you should do after training the legs. I do cardio myself. It all depends on your goal and your physical abilities.
Isometrics done properly are a strength exercise themselves. So they can be done anytime as long as you have had a proper warmup and don't overdo them.
i guess it depends on your recovery, PNF leaves some folk pretty sore. if you do PNF monday and are sore for you leg workout on tuesday that isnt much help is it? depends on the individual i suppose.