قارن الطرق

	نسبة التبادل التنفسي	القدرة الحرجة (مونود)
المجال	علوم الرياضة	علوم الرياضة
العائلة	Hypothesis test	Hypothesis test
سنة النشأة	1949	1965
صاحب الطريقة	J. B. Weir	Henry Monod
النوع	expired gas analysis	power-duration model
المصدر التأسيسي	Weir, J. B. (1949). New methods for calculating metabolic rate with special reference to protein metabolism. Journal of Physiology, 109(1-2), 1-9.	Monod, H., & Scherrer, J. (1965). The work capacity of a synergic muscular group. Ergonomics, 8(3), 329-338.
الأسماء البديلة	RER, respiratory quotient, RQ, substrate oxidation ratio	CP model, power-duration relationship, anaerobic capacity, critical torque
ذات صلة	5	5
الملخص	The respiratory exchange ratio (RER), also called the respiratory quotient (RQ), is the ratio of carbon dioxide produced to oxygen consumed during metabolism. Introduced by J. B. Weir (1949), RER is a non-invasive indirect measure of substrate utilization—indicating whether the body is primarily oxidizing carbohydrate, fat, or protein. RER values range from approximately 0.7 (pure fat oxidation) to 1.0 (pure carbohydrate oxidation) and higher under anaerobic conditions. By measuring exhaled and inhaled gases during exercise, RER reveals which fuel source predominates at different intensities, providing insights into metabolic flexibility and exercise physiology.	Critical power (CP) is the highest power output that can be sustained indefinitely without fatigue, representing the boundary between sustainable and unsustainable exercise. Introduced by Henry Monod and Scherrer in 1965, the critical power model describes the hyperbolic relationship between power output and time-to-exhaustion. The model partitions work capacity into two components: critical power (the aerobic ceiling) and anaerobic work capacity (the maximal work that can be performed above critical power before depletion). This framework is widely used in exercise physiology, sports science, and occupational biomechanics.