Lastly, there are advanced techniques that require one not to "lose their Jing" during the practice period. If you are practicing a method like this, your master would have informed you this is the case, and it is highly advisable to follow the instructions. Otherwise, if you look at the techniques I will be providing, they are safe techniques that allow for a balanced life style - although, the loss of Jing may set you back, it does not take you back to zero, but simply means there may be less energy the following day when you practice. If practicing Kung Fu with these techniques, then try not to train so hard the next day, but save it for a different day.