Fat Cells Are Like Bacteria

When you treat bacterial infections with antibiotics, the surviving bacteria pass their resistance on to their offspring, producing a strain of bacteria that is resistant, or even immune to the antibiotic used. Fat cells seem to behave the same way when subjected to diet and/or exercise programs. They eventually become resistant to whatever you're doing. Bodybuilders have known this for years. They even have an acronym describing the problem. S.A.I.D., or Specific Adaptation to Increased Demand.

The only solution to the problem is to vary your diet, your exercise routine, or both. Once you have a sound aerobic base, you can branch out into strength training, aerobic activities that work other muscle groups, etc. A cyclist might add swimming, or even (shudder) running to his training program.

Diet can be tailored to the exercise program's variations. You could mix a low-carb diet with a week of primarily weight workouts. A high-carb, low-fat diet would go well with a week of long bike rides. The idea is to keep your metabolism from settling into a routine until you've reached your target weight.