Collected Fitness Info


Wednesday, May 14, 2003
Patrick- carb

Marshall, if possible can you please indicate how many calories your client is taking in and the type, frequency and duration of his current workouts so that we can provide more specific assistance to you and your client. Cutting carbohydrate foods from your clients diet results in diminished energy but it also produces a frequently fatigued body not capable of performing even near maximal potentials. The fact is you need carbohydrates for your brain, heart and muscles among other vital organs. The main fuel of the brain and central nervous system is glucose, which is most easily obtained from carbohydrates. If carbohydrates remain unavailable for several days the body attempts to conserve essential protein by producing an alternative fuel source known as ketones, from the partial burning of fatty acids. As the breakdown continues, these ketones build in the blood causing an abnormal condition called ketosis. Initial weight loss is NOT fat but water from the kidney’s attempting to rid the body of excess ketones. Ketogenic diets make the blood more acidic, upsetting the body’s chemical balance and causing potentially serious and unpleasant side effects like headaches, bad breath, dizziness, fatigue and nausea. In addition, Fat can only be metabolized via Krebs cycle oxidation. It is essential to recognize that a reduction in Krebs cycle intermediates due to low or no carbohydrate diets will result in a diminished rate of ATP production from fat metabolism. When carbohydrate stores are depleted in the body, the rate at which fat is metabolized is reduced. Therefore carbohydrates are essential in the ability to metabolize fat. It is only the free fatty acids that are metabolized via the Krebs cycle that are used in ATP production that go toward reducing body fat levels.
The truth is, there is no scientific evidence to support that this theory will translate into improved body composition or fat loss. It is true that a large volume of weight will be lost as glycogen (stored carbohydrate) depletes in the muscle and liver, but this weight is from water, not fat loss. This will not help body composition or overall health. It is also true that the body will rely more on free fatty acids for fuel when muscle glycogen is depleted, but the body will rely much more on amino acids (protein) supplied from the breakdown of lean tissue as well. So while you may burn fat, you will also burn more muscle. In addition to this, individuals on a carbohydrate-restricted diet have lower energy levels and experience shorter time to fatigue during exercise. This means that workouts will likely be cut short and lower in intensity. In general, helping your clients in controlling their weight is not a particularly complex process. Regardless of what you may read in the popular literature, no magic formula exists for weight loss. In simple terms, to lose weight, you must expend more energy (calories) than you consume. This is known as thermodynamics. Thermodynamics is NOT a theory or a fad. Thermodynamics is the branch of physiochemical science concerned with heat and energy and their conversions one into the other involving mechanical work.