Category: P

Pituitary dwarfism (sometimes called proportionate dwarfism) is a condition of growth retardation characterized by children who are very short in stature but have normal body proportions. It is caused by a dysfunction of the pituitary gland (Tish, 1999). Pituitary dwarfism is caused by a lack of growth hormone (GH) produced by the pituitary gland, but…

The pyruvate dehydrogenase complex is responsible for converting pyruvate to acetyl CoA in the cytosol of a cell. When pyruvate is produced from glucose during glycolysis, for further metabolism via Krebs cycle, it must first be converted to acetyl CoA. The pyruvate dehydrogenase complex requires many enzymes and cofactors to accomplish this reaction. Cofactors involved…

Pycnogenol is an extract from French maritime pine bark (Pinus maritima), and is considered to be a strong and direct antioxidant and therefore is used as a dietary supplement. Pycnogenol is claimed to alleviate inflammations, improve cardiovascular function, inhibit tumor initiation, and inhibit angiotensin-conversion enzyme. It has been suggested to take part in the prevention…

Sparing of body protein is important for maintenance of lean body mass. Adequate energy and protein intake are vital to prevent catabolism of lean tissue. Dietary carbohydrate is well known for its protein-sparing effects. Sparing protein is of particular importance for an athlete during periods of weight loss, in which maintenance of lean body mass…

Protein powders are used in drink mixes to provide supplementary protein to the diet. Many preparations of protein powders have been developed and often include whole milk proteins, whey protein, casein, soy protein, egg albumin, and combinations of these. Although drinks produced from protein powders can offer a convenient source of protein and essential amino…

Many athletes focus on proper food consumption in the hours and moments just prior to exercise or competition. Williams has outlined several guidelines that should be used by athletes during the meal prior to competition. These recommendations include consumption of a meal providing foods that will allow the stomach to be relatively empty before the…

Proper nutrition after exercise can be extremely important, especially following vigorous training sessions or for events that take place on consecutive days. For endurance athletes, the primary goal for postexercise nutrition is to replace lost glycogen stores, while for resistance training the goal is to promote protein synthesis to maintain or enhance lean body mass.…

Phosphoplipids belong to a large family of molecules containing both lipid and phosphate components (such as glycerophosphatides, sphingolipids, etc.). In particular, glycerophosphatides consist of a glycerol bound to two fatty acids and a phosphate molecule that is linked to one of many compounds including choline, serine, ethanol- amine, and inositol. Phosphatidyl choline, also known as…

Phosphate salts of sodium and potassium have been proposed to be ergogenic for several reasons. Proposed mechanisms include increased availability of phosphate for oxidative phosphorylation and phospho- creatine synthesis, production of 2,3-diphosphoglycerate, which is important for delivery of oxygen to tissues via hemoglobin, and buffering the accumulation of hydrogen ions in the blood, thus maintaining…

Phosphagens are compounds that possess a high-energy phosphate bond that when broken produces energy that can be used to drive biochemical reactions such as muscle contraction, active transport, and biosynthesis. Adenosine triphosphate (ATP) is most commonly used for these purposes within the body. Another important phosphagen is creatine phosphate, which is used extensively to restore…