AJP - Regulatory, Integrative and Comparative Physiology, Vol 246, Issue 6 963-R967, Copyright © 1984 by American Physiological Society
Heart rate and energy expenditure in resting and running Svalbard and Norwegian reindeer
K. J. Nilssen, H. K. Johnsen, A. Rognmo and A. S. Blix
The purpose of this study was to determine whether a convenient
relationship could be found between heart rate (HR) and energy expenditure
at rest and during running in the high arctic Svalbard reindeer (SR) and
the subarctic Norwegian reindeer (NR). Measurements of HR and energy
expenditure (O2 consumption) were made at different ambient temperatures,
at rest, and during running at different speeds during both summer and
winter. Cost of transportation (Science 177: 222-228, 1972) was 3.56 and
2.67 J X g-1 X km-1 in SR and NR, respectively. The y-intercept value
obtained for NR was close to the predicted value (J. Exp. Biol. 97: 1-22,
1982), whereas that of SR was much lower. In NR the relationship between HR
and energy expenditure at running speeds from 0 to 9.2 km X h-1 is,
regardless of ambient temperature (in the -30 to +10 degrees C range),
described by the following equations: y = 8.04x + 48.70, r = 0.92, n = 27
(summer); and y = 7.48x + 31.20, r = 0.95, n = 52 (winter). In SR, the
corresponding equations were y = 7.60x + 49.20, r = 0.94, n = 29 (summer);
and y = 8.90x + 32.10, r = 0.96, n = 44 (winter), where y is HR (beats X
min-1) and x is metabolic rate (W X kg-1).
