atmika.
do not go above 6 cm.
if you want a good life be safe and get 6 cm.
I personally asked Dr. Lee what he thought about this (lengthening past 6 cm) and he has told me that from his experience in talking to former lengthening patients (2-3 years post recovery) those that only lengthened 5 cm recovered fully and their previous athleticism returned close to 100% to pre-LL levels. On the other hand, those who chose to lengthen between 6 and 7 centimeters recovered 100% in performing daily functions (walking, light jogging, etc), BUT only recovered about 60-70% of their pre-LL athleticism when engaging in serious sports/strenuous activities (full sprinting, jumping, basketball, rugby, etc..). Additionally, those that lengthened beyond 7 cm saw an ever greater decline in their previous athletic abilities.
6cm is a massive amount like you can not believe, it will change your life, get tibia first, if yor still not happy then you could get femurs but you wont need it. trust me.