How to avoid doing things that suck the energy out of you? A recent answer on this site was as follows.


  To make a strong commitment, you want to cultivate right effort by making a continuous effort, by hanging out with wise spiritual friends, by balancing energy with concentration and by not doing things that suck the energy out of you like reacting to your arising defilements, eating too much and getting lost in mental proliferation.


I would love an explanation, specifically, about the part in it which I highlighted in bold (i.e. about "sucking energy" and "reacting to defilements").
My questions include:


What are all the things that "suck our energy" ? 
Why does reacting to defilements suck our energy ? 


Everything else people want to add about this subject will be welcomed.
This is one of the things you learn from a live teacher, not usually found in books. Briefly, few of the main points I was taught, in no particular order:


ego - a lot of energy is spent on defending the self-image, rationalizing, finding excuses etc.
negative/pessimistic thinking - another major energy hog is thinking of the kind "things are wrong and are impossible to fix", excessive focusing on the issues and bad news.
masturbation and sexual activity - orgasm is traditionally considered a major point of energy loss.
non-spartan lifestyle - relaxing into one's weakness for sensuous comfort.
having no agenda - allowing other people, things, and circumstances drive you around.
inner conflict - blaming or judging oneself non-constructively.
doubt - anxious wavering back and forth.
not taking responsibility - organizing one's action around other people's approval and acceptance instead of taking ownership of one's choices.
alcohol - consumption of alcoholic beverages.
low energy food - food that is spoiled, expired, frozen and reheated, over-processed, lifeless, and generally bad quality.
posture - an important factor of energy loss is a posture and gait that moves the body weight off the center of the feet and too much towards the toes or the heels.


I will add more points here if I remember any.