oksygenbruk

oksygenbruk is the rate at which oxygen is used by cells or tissues. In physiology, it is typically referred to as oxygen uptake or VO2, measured in milliliters of O2 per minute (ml/min) or milliliters per kilogram per minute (ml/kg/min). Resting VO2 is about 3.5 ml O2 per kg per minute, approximately 0.25 L/min for an average 70 kg adult. Maximal oxygen uptake (VO2 max) reflects cardiorespiratory fitness and can range from about 2–3 L/min in untrained individuals to 4–6 L/min or higher in elite endurance athletes.

Measurement is usually performed with cardiopulmonary exercise testing (CPET) using a metabolic cart to analyze expired gases during graded exercise. The Fick principle links VO2 to cardiac output (CO) and the arterial-venous oxygen difference (CaO2–CvO2): VO2 = CO × (CaO2 – CvO2).

Factors influencing oksygenbruk include heart function, lung function, physical conditioning, age, sex, and disease.

In addition to human physiology, the term is also used in ecology to describe the oxygen consumption rate of organisms in respirometry experiments. Applications include assessing metabolic rate, evaluating exercise capacity, diagnosing and monitoring cardiopulmonary conditions, and guiding rehabilitation and training programs.