Well, I didn't eat very much prior to exercising. If I tried reducing my diet by 25%, I have to wonder if my body would go into starvation mode or if anyone would want to be near me for fear of rabid bodily harm. LOL
There were too many variables, mainly unknown, which caused me to pause. The sample size was small. What type of exercises did the 12 dieters/exercisers do? How many hours during the day did they exercise? Did the type of workouts increase in difficulty or duration the healthier those 12 participants became? How overweight were the participants? the control group volunteers? And, though 6 months does seem like an adequate amount of time, would it have been for someone carrying an additional 100 pounds? Would they get the same results for someone wanting to lose only 10 to 15 pounds?
I suppose these questions may have been addressed in the acual published report. You could always research it if you're really interested.
