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Substrate Utilization Mapping

Meaning

Substrate Utilization Mapping is the precise clinical assessment and quantification of which energy substrates—carbohydrates, fats, or protein—an individual’s body is preferentially using for fuel under various metabolic conditions, such as rest, exercise, or fasting. This mapping is achieved through indirect calorimetry or advanced metabolic testing to determine the Respiratory Quotient (RQ) or Respiratory Exchange Ratio (RER). The data provides a direct measure of metabolic flexibility and efficiency, serving as a critical guide for individualized nutritional and exercise programming to optimize hormonal and metabolic health.