After my 2nd pregnancy, my tummy is very flabby, like a water bed (I used to describe to my bestEST fren, haha..) I asked my yoga teacher, is there any exercise that is effective to firm my tummy. She teach me this,
1) Lie straight on the floor
2) Raise both your legs 90 degree
3) For 10 minutes (I mean do not move your 90 degree legs for 10 minutes)
I thought the yoga teacher was joking with me, this is too easy to do I thought... and I try it at home, wah lau... dont play play leh, it is so hard to keep your legs up for 10 minutes. U try and see.
Besides that, if you feel that your legs are very tiring, then u are exercising on the wrong area. Your tummy should be the area that feel tire after this exercise.