I have struggled with fitness my whole life, and I have realized that not everyone is genetically disposed to the same effects of specific exercises. However, I believe that most people can get in shape, it's just a function of resistance.

Diet and fitness is one of those things in life where you should just overkill the plan. Keep your diet stricter than you have to, lift more weights than you have to, do more cardio than you have to.

When you overkill the situation, you will get in and stay in excellent shape, trying to walk the line of "just enough" gets your burned and loses precious time towards proper progress.