Active Jobs Make a Big Difference
As a trainer, it is EXTREMELY easy to make those with active jobs lose fat. Give them a few extra workouts a week, make them adhere to a healthy diet, and watch them lose fat at an incredible rate. For the sedentary individual this happens MUCH slower as one would expect by the numbers above. They need to have their nutrition near perfect in order to lose fat at a considerable rate.
I Became Sedentary
Knowing this, I became even stricter on my nutrition thinking I could still lose some fat at a slower pace. Thinking my calculations were correct, I watched myself get softer even though I was eating VERY healthy and lower calories. I experienced how hard it was to lose fat with a sedentary lifestyle and only doing 3-4 light-moderate workouts a week. In fact, my bodyfat percentage went up over this time.
Once things started to heal enough to where my daily activity was restored, I resumed activities like hours of yard work and hiking. Amazingly the fat started to melt off. This experience really made me realize how important daily activity is for those at a desk 40-60 hours a week.
Make Up Those Non-active Hours
Walking does help, but from a fat loss perspective you have to do something with a higher intensity in order to reap the benefits of a leaner body. Walking is a very healthy thing to do, but it only works for fat loss if your heart rate is significantly elevated, you do it for many hours a day, or if you are very deconditioned.