title: Pulse rate and ventilation as indices of habitual activity. I. Theoretical aspects.
mesh_terms: D000367:Age Factors; D000531:Altitude; D001831:Body Temperature; D002940:Circadian Rhythm; D004644:Emotions; D006801:Humans; D008433:Mathematics; D009747:Nutritional Physiological Phenomena; D010101:Oxygen Consumption; D005082:Physical Exertion; D011674:Pulse; D012119:Respiration; D012129:Respiratory Function Tests; D012737:Sex Factors; D013312:Stress, Physiological