ABSTRACT
Proper food intake provides an uninterrupted supply of energy and tissue-building chemicals to sustain life. For exercise and sports participants, the ready availability of specific nutrients takes on added importance because physical activity increases energy expenditure and the need for tissue repair and synthesis. Nutrient uptake by the body involves complex physiological and metabolic processes that usually progress unnoticed for a lifetime. Hormones and enzymes work in concert throughout the digestive
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absorbable subunits. Substances produced during digestion are absorbed through the thin lining of small intestine and pass into blood and lymph. Self-regulating processes within the digestive tract usually move food along at a slow rate to allow its complete absorption, yet rapid enough to ensure timely delivery of its nutrients.
