I've known this for ages- it's really common sense... you have to fuel your body with good foods if you want to feel good and have the energy to exercise. The concept is not a difficult one to grasp, yet here I am huffing and puffing after a 2 mile run and feeling like **** because I ate a large size tater tot less than 2 hours ago.
I work my butt off all day long and work out hard! I put so much effort in, and I recently began HIIT (high interval training) to burn a lot of calories in a short amount of time. This makes me HUNGRY! And when I get this hungry, it seems the only foods I crave are the worst kinds! It makes sense when I think about it- I mean whether it's mental or physical, my body knows these foods are super high in calories- it just seems like if I can realize THAT on a subconscious level, I'd be able to remember "THIS WILL HURT ME IN THE LONG RUN!"
Sorry, had to vent a bit. It's just frustrating because it took a lot to gain control of my eating habits and to start eating healthy, balanced meals so I could start working out every day to get to more advanced workouts which in turn sabotage my diet..... GRRRRRRR!
we all go through it. It's a tough pill to swallow (cravings that is) and they might get the best of us at times. You can do it 
Perhaps you are not getting enough protein and/or calories in your diet regularly. Many times consistent deprivation leeds to binging.
