I'm a Physical Therapist with 38 years experience in Orthopedics and Rehabilitation. I also spent 4 years as the exercise consultant for a surgical Bariatric program. While in graduate school I studied Anatomy, Physiology, Exercise Physiology, and Kinesiolgy. Fact: the amount of fat cells in your body is established between ages 3 and 4. Your never lose or gain the established fat cells. When you gain fat, the cells expand, when you lose fat the fat cell shrink, but never disappear. When you eat more calories than your body needs, whether it comes from carbohydrates, protein or fats, these calories are turned into fatty acid. These fatty acids enter into fat cell where 3 fatty acids join with glycerol to from triglycerides. These triglycerides are too large to pass through the fat cell wall. With aerobic exercise the hormone epinephrine is released and stimulates the fat cell membrane and leads to the activation of the fat-splitting enzyme lipase. Lypiase splits the triglyceride molecule, and the fatty acids are free to
circulate getting to the working muscles. When the exercise is to intense lactic acid begins to appear in the blood indicating you are no longer in the aerobic phase of exercise, but the anaerobic phase. In anaerobic exercise lactic acid builds up in the blood creating an oxygen debt. Lactic acid also blocks the action of epinephrine thereby reducing the availability of fat for muscle metabolism. That's why it is important to exercise within your aerobic training zone. As you become more physically fit you can raise your aerobic threshold, thus exercise more intense and more fat can be mobilized and made available for use as an energy source. As the exercise consultant for the bariatric program I experienced how important exercise can be to lose fat. After surgery, our clients couldn't eat solid food, but were given a liguid supplement high in protein, moderate carbohydrates and low in fat. The high proteins were used to discourage the body from metabolizing existing muscles to make up for the calories it was not getting. I also told my clients they must exercise aerobically at least 30 minutes per day 4-5 days a week and to add strengthening exercises at least 2 days a week to conserve their muscle mass. We checked all clients weekly for the first 4 weeks using a medical grade body analyzer. All clients lost weight, the clients that exercised lost weight, which was between 80 to 90 percent fat and lost minimal lean body mass(muscle). Those that didn't exercise lost weight, but their percent body fat increased due to the lose of lean body mass(muscle). I recently spoke with a Registered Dietitian with a masters in Nutrition. I asked about fasting, IF, and cleansing. Her opinion was that fasting and IF could lead to unwanted consequences mainly lose of muscle mass and that cleansing was unnecessary because our bodies do a good enough job of cleansing itself. She stated that a diet that restricted more than 1000 calories per day could lead to the same consequences as IF.
I gram of fat contains 9 calories while 1 gram of carbohydrates and protein contain 4 calories, this is the main reason it is so hard to lose fat, because fat is the most efficient method for the body to store what it senses it may need to prevent starvation. In a book by Brian Sharkey an Exercise Physiologist at the University of Montana writes" One pound of fat has the energy equivalent of 3,500 calories. Thus 3,500 calories must be expended to reduce 1 pound of weight, hopefully fat. Conversely, 3,500 calories of excess dietary intake will lead to an additional pound of body weight. The daily activity of a young man who weighs about 154 pounds, consists of light office work and does not engage in any physical activity will require a daily caloric need of about 2,400 calories" This number is consistent with my statement in an earlier post that stated an average individual needs about 15 calories per pound per day. In summary, diets without exercise will never cause you to lose fat, and the weight you lose will be gained back if you return to your normal eating habits and same behaviors. To lose fat you should combine sensible eating with an exercise program that combines aerobic exercise and strength training. These opinions of mine are based on education and experience. If you agree with them good, if not, then can we agree to disagree using civil discourse?
