Summary
Although many studies indicate that the spontaneous breathing frequency minimizes breathing work, the consequences of this for exercise energetics have never been investigated. To see if the spontaneous exercise breathing frequency minimizes oxygen uptake, we compared\(\dot V_{{\text{O}}_{\text{2}} }\) during treadmill walking (2/3\(\dot V_{{\text{O}}_{\text{2}} }\) max) at several alternative frequencies. The alternative frequencies ranged from the lowest sustainable to a frequency twice the spontaneous value. All eight subjects adjusted tidal volume to comfort. Exercise oxygen uptake was constant, independent of breathing frequency. At the same time, minute ventilation rose to be 65% greater at the highest frequency than at the lowest (P<0.01). We then reproduced the various exercise frequencies, tidal volumes, and ventilations during seated isocapnic hyperpnea to measure\(\dot V_{{\text{O}}_{\text{2}} }\) with locomotory muscles at rest. Once again, oxygen uptake was constant, independent of breathing frequency. We conclude that the spontaneous exercise breathing frequency fails to minimize\(\dot V_{{\text{O}}_{\text{2}} }\) during either exercise or resting reproduction of exercise ventilation.
Similar content being viewed by others
References
Bartlett RG, Brubach HF, Precht HS (1958) Oxygen cost of breathing. J Appl Physiol 12: 413–424
Bechbache RR, Duffin J (1977) The entrainment of breathing frequency by exercise rhythm. J Physiol [Lond) 272: 553–561
Bouhuys A (1964) Distribution of inspired gas in the lungs. In: Fenn WO, Rahn H (eds) Handbook of physiology, sec. 3, Respiration. Am Physiol Soc, Washington, pp 130–171
Clark FJ, Euler C von (1972) On the regulation of depth and rate of breathing. J Physiol [Lond] 222: 267–295
Dempsey JA, Gledhill N, Reddan WG, Forster HV, Hanson PG, Claremont AD (1977) Pulmonary adaptation to exercise: effects of exercise type and duration, chronic hypoxia, and physical training. Ann NY Acad Sci 301: 243–261
Gautier H (1980) Control of the pattern of breathing. Clin Sci 58: 343–348
Grunstein MM, Younes M, Milic-Emili J (1973) Control of tidal volume and respiratory frequency in anesthetized cats. J Appl Physiol 35: 463–476
McIlroy MB (1954) The work of breathing in normal subjects. Clin Sci 13: 127–136
Martin BJ, Stager JM (1981) Ventilatory endurance in athletes and non-athletes. Med Sci Sports Exerc 13: 21–26
Mead J (1960) Control of respiratory frequency. J Appl Physiol 15: 325–336
Melissinos CG, Mead J (1977) Maximum expiratory flow changes induced by longitudinal tension on the trachea in normal subjects. J Appl Physiol 43: 537–544
Milic-Emili G, Petit JM, Deroanne RT (1960) The effects of respiratory rate on the mechanical work of breathing during muscular exercise. Int Z Angew Physiol 18: 330–340
O'Cain CF, Dowling NB, Slutsky AS, Hensely MJ, Strohl KP, McFadden ER Jr, Ingram RH, Jr (1980) Airway effects of respiratory heat loss in normal subjects. J Appl Physiol 49: 875–880
Otis AB, Fenn WO, Rahn H (1950) Mechanics of breathing in man. J Appl Physiol 2: 592–607
Roos A, Dahlstrom H, Murphy JP (1955) Distribution of inspired air in the lungs. J Appl Physiol 7: 645–659
Secher NH, Clausen JP, Klausen K, Noer I, Trap-Jensen J (1977) Central and regional circulatory effects of adding arm exercise to leg exercise. Acta Physiol Scand 100: 288–297
Shephard RJ (1966) The oxygen cost of breathing during vigorous exercise. Q J Exp Physiol 51: 336–350
Winer BJ (1962) Statistical principles in experimental design. McGraw-Hill, New York, pp 77–85
Author information
Authors and Affiliations
Consortia
Additional information
Supported in part by NIH Grant HL 26351
Rights and permissions
About this article
Cite this article
Kennard, C.D., Martin, B.J. & Physiology Section/Medical Sciences Program. Respiratory frequency and the oxygen cost of exercise. Europ. J. Appl. Physiol. 52, 320–323 (1984). https://doi.org/10.1007/BF01015218
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF01015218