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close this bookBibliography of Studies of the Energy Cost of Physical Activity in Humans (London School of Hygiene and Tropical Medicine, 1997, 162 p.)
close this folder4. Adults
close this folder4.4 Standardized activities
Open this folder and view contents4.4.1 Men
Open this folder and view contents4.4.2 Women
View the document4.4.3 Men & women

4.4.3 Men & women

1. Banerjee B & Saha (1972): Effect of temperature variation in a climatic chamber on energy cost of rest and work. Environ.Res. 5, 241-247.

Energy expenditures with some common daily activities of 10 male and 10 female medical students were measured at the room temperature of 29°, and at 18° and 38° in a climatic chamber. The increased resting metabolic rate and energy cost for different activities in hot and cold temperatures were found to be not significantly higher than that for room temperature except in a few categories. The energy cost for all the activities was found to be lower than that reported in Western figures.

2. Bhambhani Y & Singh M (1985): Metabolic and cinematographic analysis of walking and running in men and women. Med.Sci.Sport Exerc. 17, 131-137.

The purposes of this study were to compare the total metabolic costs and gait patterns of walking and running at self-selected, comfortable speeds in males and females. Total oxygen consumption was used to determine the metabolic cost, and cinematographic analysis was used to study the gait patterns of walking and running a distance of 1 km in 12 male and 12 female subjects. No significant sex difference was observed for the speed, vertical lift per stride, and total vertical lift per km of distance walked. Females ran at a significantly slower speed than males (P less than .01), but no significant sex difference was observed for the vertical lift per stride or total vertical lift per km of distance run. In both sexes, the gross and net energy costs of running were significantly greater (P less than .001) than those of walking when values were expressed as kcal . kg-1 . km-1 or cal . kg-1 . stride-1. No significant sex difference was observed in the gross or net metabolic cost of walking, whereas during running, the gross and net metabolic costs in kcal . kg-1 . km-1 were significantly higher (P less than .05) in females than in males. It was hypothesized that this sex difference was due to the cumulative effect of several factors which were biomechanical and metabolic in nature.

3. Bransford DR & Howley ET (1977): Oxygen cost of running in trained and untrained men and women. Med. Sci. Sports Exerc. 9, 4 1 -44.

The purpose of this study was to compare the oxygen cost of running as it relates to speed of running among the following four groups: trained male distance runners, trained female distance runners, untrained but active men and women. Each subject was given a series of treadmill tests during which Vo2 was measured at submaximal work loads. The linear regression equation was utilized to compute the relationship between Vo2 and running speed for each groups. The results indicated that the rate of increase in Vo2 for a given increase in running speed could be represented as a straight line and was the same for all groups (P greater than .05). The trained male runners had a significantly lower Vo2 (P less than .05) than those of the other three groups at any measured speed. The trained females and untrained males had significantly lower Vo2s than the untrained females (P less than .05) at any of the given range of speeds. No significant differences were observed between the untrained mean and trained women (P greater than .05). It was concluded that there were differences in the oxygen cost of running not only between the trained and untrained groups but also between males and females.

4. Brehm BA & Gutin B (1986): Recovery energy expenditure for steady state exercise in runners and nonexercisers. Med.Sci.Sport Exerc. 18, 205-210.

This study examined the effects of intensity, mode of exercise, and aerobic fitness on the energy expended during recovery (recovery oxygen consumption, or rec VO2 following steady state exercise. Eight runners (4 males, 4 females; 22-32 yr) walked at 3.2 and 6.4 km X h-1 and ran at 8.1 and 11.3 km X h-1 (18, 33, 50, and 68% peak VO2 All subjects completed 3.2 km of walking or running each session. Eight sedentary adults (4 male, 4 female; 21-33 yr) completed the 6.4 km X h-1 test. For the runners, net rec VO2 for 3.2, 6.4, 8.1 and 11.3 km X h-1 exercise was (X +/-SE) 12.52 +/- 3.00, 29.53 +/- 5.41, 28.64 +/- 2.91, and 44.27 +/-5.32 ml X kg-1, respectively, for the recovery period (18-48 min). Differences among group means were significant (P less than 0.05), except between 6.4 and 8.1 km X h-1 walking (29.53 +/-5.41 and 35.09 +/- 9.39 ml X kg-1). Statements attributing substantial energy expenditure to the recovery period may be misleading to people exercising at levels similar to those described in this study, since the recovery energy expenditure only amounted to approximately 13-71 KJ (3-17 kcal).

5. Bunc V & Heller J (1989): Energy cost of running in similarly trained men and women. Eur.J.Appl.Physiol 59, 178-183.

Physical Culture Research Institute, Charles University, Prague 1, Czechoslovakia. The energy demand of running on a treadmill was studied in different groups of trained athletes of both sexes. We have not found any significant differences in the net energy cost (C) during running (expressed in between similarly trained groups of men and women. For men and women respectively in adult middle distance runners C = 3.57 +/- 0.15 and 3.65 +/-0.20, in adult long-distance runners C = 3.63 +/- 0.18 and 3.70 +/- 0.21, in adult canoeists C = 3.82 +/- 0.34 and 3.80 +/- 0.24, in young middle-distance runners C = 3.84 +/- 0.18 and 3.78 +/-0.26 and in young long-distance runners C = 3.85 +/- 0.12 and 3.80 +/- 0.24. This similarity may be explained by the similar training states of both sexes, resulting from the intense training which did not differ in its relative intensity and frequency between the groups of men and women. A negative relationship was found between the energy cost of running and maximal oxygen uptake VO2max expressed relative to body weight (for men r = -0.471, p less than 0.001; for women r = 0.589, p less than 0.001). In contrast, no significant relationship was found in either sex between the energy cost of running and VO2max We conclude therefore that differences in sports performance between similarly trained men and women are related to differences in The evaluation of C as an additional characteristic during laboratory tests may help us to ascertain, along with other parameters, not only the effectiveness of the training procedure, but also to evaluate the technique performed.

6. Bunc V, Heller J. Sprynarova S & Leso J (1988): Relationship between energy expenditure and running speed in laboratory. In: Exercise physiology: current selected research. edited by C.O. Dotson, et al, pp. 121-131. AMS Press, Inc. New York.

Running on the treadmill is one of the most often used means for determining functional capacity and/or fitness in the laboratory. It is possible to assume that the degree of mechanical and metabolic adaptation to this work load would be mostly marked according to its biomechanical similarity to walking. The energy output for running expressed indirectly by oxygen uptake per kg body weight (VO2/kg) can be calculated from the velocity of running (v) with the help of various monographs or equations. These relationships are linear in the range of submaximal work loads, approximately in range 20-90% of maximal aerobic power VO2max The relationship between VO2/kg and running speed are influenced by the degree of training, i.e. adapting to this work load (which changes mostly the mechanical efficiency) and also by sex and natural talent for running. On the basis of our measurements on the treadmill in differently trained athletes (long-distance runners, middle distance runners of both sexes and cross-country skiers) and untrained persons of middle age, supplemented by data from other authors, it was possible to demonstrate these relationships in a range limited on the bottom by an equation VO2(kg/ml)=2.950.v(km/h)+2.000, and the top by the equation VO2(kg/ml)=2.800.v(km/h)+14.000. An equation independent on training state was established for women: VO2(kg/ml)=2.756.v(km/h)+8.516, with maximal error about 10%, and a similar equation for men VO2(kg/ml)=3.1154.v(km/h)+3.886 with the same error. Finally, a general equation was established for the relationship between energy output and running speed on the treadmill: VO2(kg/ml)=2.875.v(km/h)+8.000, with a maximal error about 12%. These equations can be used for the running with a speed lower than 13 km/in even under field conditions, e.g. for doing daily or weekly exercise, For increasing energy output above a certain level so as to improve fitness or reduce body weight, etc.

7. Butts NK, Dodge C & McAlpine M (1993): Effect of stepping rate on energy costs during StairMaster exercise. Med. Sci. Sports Exerc. 25, 378-382 .

Human Performance Laboratory, University of Wisconsin-LaCrosse, Wl 54601. The responses to a self-selected stepping pattern (random) on a StairMaster 4000PT were compared with those obtained in response to the rates established by the manufacturer (cadence) in men (N = 14) and women (N = 14). During the random test the subjects stepped at their own natural, self-selected rate and distance. In cadence trial the subjects were required to step in time with a metronome at predetermined rates of 60, 77, 95, and 112 steps.min-1. Each trial consisted of four, 5-min continuous workloads during which HRs were recorded and expired air was analyzed using an automated open-circuit gas system each minute. All size dependent variables (i.e., VE and (O2.min-1) as well as relative VO2 ( were significantly (P < 0.01) higher for the men across all stages and between methods. Although the random test produced slightly higher oxygen consumption values than the cadence trial, these differences were not significant (P > 0.05). The actual METs were significantly (P < 0.01) higher at all stages except at the lowest stepping rate for both methods compared with those estimated by the manufacturer. Equations were established to estimate actual MET costs: Men's METs = 2.675 + 0.935 (rate); women's METs = 2.934 + 0.817 (rate). Cross-validations of 0.975 and ().957 were obtained on an additional group of men (N = 8) and women (N = 11), respectively.

8. Butts NK, Knox KM & Foley TS (1995): Energy costs of walking on a dual-action treadmill in men and women. Med.Sci.Sport Exerc. 27,121-125.

Department of Exercise and Sports Science, University of Wisconsin--LaCrosse 54601. The physiological responses of normal walking and walking on a dual action treadmill which incorporates arm exercise were compared in 29 men and 37 women. Subjects completed six, 5-min steady-state exercises at 2.0, 3.0, and 4.0 mph (0.89, 1.34, 1.79 m.s-1) and 3% incline with and without arms. Estimated METs calculated according to the ACSM equations were compared with the actual METs. The men's ventilation (VE), and VO2 (I.min-1,, and METs) were significantly (P < 0.001) higher at all speeds and for both conditions than the women's. There were no gender differences (P > 0.05) in heart rates (HR), respiratory exchange ratio, and ratings of perceived exertion (RPE) for each condition. The arm conditions yielded significantly (P < 0.001) higher responses at each speed for VE, l.min-1,, METs, RPE, and HR. Although there were no significant (P < 0.05) differences in HR between men and women for each condition, the relationships between and HR differed. The actual METs obtained during the arm conditions were significantly (P < 0.05) higher than those estimated for both the men and women at all speeds. It was concluded that using the arms while walking on a dual action treadmill increases the energy costs an average of 55% above normal walking.

9. Carroll MW, Otto RM & Wygand J (1991): The metabolic cost of two ranges of arm position height with and without hand weights during low impact aerobic dance. Res.Q.Exerc.Sport, 62, 420-423.

Human Performance Lab, Adelphi University, Garden City, NY 11530. To determine the energy cost of low impact aerobic dance while varying arm movement height and the use of hand weights, 10 adults volunteered to participate in four choreographed trials. All trials consisted of identical leg movements. Arm movements, however, were performed above shoulder level both with and without 0.9-kg hand weights and below shoulder level both with and without 0.9-kg hand weights. Open circuit spirometry was employed throughout the 10-min videotape guided trials, and heart rate was measured by telemetry. Neither the use of hand weights nor the change in arm position height significantly altered the energy cost of low impact aerobic dance. However, heart rate responses were significantly different.. Caution should be observed by aerobics instructors and participants as to the use of heart rate as an indicator of intensity for low impact aerobic dance.

10. Cassady SL & Nielsen DH (1992): Cardiorespiratory responses of healthy subjects to calisthenics performed on land versus in water. Phys. Ther. 72, 532-538.

Physical Therapy Graduate Program, College of Medicine, University of , lowa City 52242. This study evaluated the oxygen consumption (VO2) and heart rate response curves for standardized upper- and lower-extremity exercise on land and in water. Forty healthy subjects performed one upper-extremity and one lower-extremity exercise at three selected cadences on land and in water. Steady-state heart rate was determined by electrocardiographic radiotelemetry and expressed as a percentage of age-predicted maximal heart rate (% APMHR). Percentage of age-predicted maximal heart rate was used as the criterion measure of relative exercise intensity. Oxygen consumption was determined by the open-circuit method. Results indicated systematic increases in VO2 from 2 to 9 metabolic equivalents (METs) (1 MET = 3.5 mL and % APMHR from 45% to 73% with increased cadence. The VO2 responses were highest during water exercise, whereas % APMHR was greater during land exercise. Based on the magnitude of the responses, water calisthenics appear to be of sufficient intensity to elicit training adaptations. Training studies are needed to document these changes.

11. Claremont AD & Hall SJ (1988): Effects of extremity loading upon energy expenditure and running mechanics. Med.Sci.Sport Exerc. 20, 167-171.

College of Health and Physical Education, Oregon State University, Corvallis 97331-6801. Physiological and mechanical consequences of running with commercially available hand and/or ankle weights were examined. Five males and three females (age 30 to 56 yr) ran for 30 min on a treadmill (0% grade) at a self-selected pace (8.9 to 13.7 km.h- 1), under randomized conditions of: (i) unloaded weights; (ii) hand weights; (iii) ankle weights; and (iv) hand + ankle weights. Respiratory gas exchange determinations, heart rates, and sagittal view film clips were obtained at selected time intervals. Highest energy expenditures and heart values were obtained for the fully loaded condition, with intermediate values measured for independent hand- and ankle-weighted trials. increased energy expenditure due to loading ranged from 5 to 8%. Lower extremity kinematics were unaffected by loading. Angular velocity and excursion of the arm segments was significantly (P less than 0.05) reduced when hand weights alone were carried. The results indicate that commercial claims of marked increases in energy expenditure during running with hand/ankle weights are exaggerated. It appears that the small actual increases in energy expenditure, the potential for increased impact forces, and the relative discomfort of carrying weights discredit running with hand and/or ankle weights as a desirable exercise alternative.

12. Cotes JE (1969): Relationships of oxygen consumption, ventilation and cardiac frequency to body weight during standardized submaximal exercise in normal subjects. Ergonomics, 12, 415427.

In normal males during submaximal exercise at a constant rate of external work on a bicycle ergometer or step test, the oxygen uptake and ventilation are linear functions of body weight. In normal females the oxygen uptakes do not differ materially from those for males of comparable weight. However, because of the constant terms in the regression equations, the convention of expressing results per kg body weight or m² body surface area may give rise to error; for ventilation this may be avoided by the use of the regression on oxygen uptake. Alternatively, the results may be reported at a constant oxygen uptake, for example, for men 1.5 I/min as recommended by l.L.O. and for women 1.0 I/min; the ventilation is then independent of body weight. By this procedure allowance is also made for differences in oxygen uptake due to the effects of practice. For the cardiac frequency a similar adjustment to a constant oxygen uptake yields values which are negatively correlated with body weight for walking on a treadmill, but not, in this instance, for standardized stepping and cycling.

13. Dal Monte A, Lupo S. Seriacopi D & Pigozzi F (1989): Energy consumption during passive isokinetic exercises. J.Sports Med.Phys.Fitness, 29, 123-128.

The energy cost and intensity of contractile muscle action incurred during passive gymnastics exercises in men and women was assessed and compared to other forms of activity. A polyfunctional isokinetic ergometer was used, which allowed tests to be performed at a constant predetermined speed and to be continued over time while the quantity of strength applied could be measured. Energy costs were determined from measuremenents of oxygen consumption made using a new telemetric system, K2 COSMED. Two groups of tests were conducted of the upper and lower limbs. The mean energy consumption of the upper limb exercises were 0.22 and 0.12 cal/kg/hr in men and women respectively, and of lower limb exercises were 0.78 and 1.39 cal/kg/hr in men and women respectively. These values are lower than those for other professional and common activities. Cardiac activity was modest and increases in heart rate were not significant. Although this type of exercise enables a passive mobilization of the joints which may be efficacious in certain situations, it is concluded that this type of exercise does not offer much assistance to those hoping to lose weight. [not original abstract]

14. Evans WJ, Winsmann FR, Pandolf KB & Goldman RF (1980): Self-paced hard work comparing men and women. Ergonomics, 23, 613-621.

Six fit male subjects (23 years, 171 cm, 67 kg, maximal VO2=2.25 (50.3 ml.kg1.min-1) and six fit female subjects (22 years, 163 cm, 57 kg, maximal VO2=1.83 mmol.kg1.min-1 (41.1 performed self-paced hard work while walking over four different terrains carrying no external load, 10 kg and 20 kg. Time on each course for individual subjects was used to determine speed and energy expenditure; heart rate was recorded as each subject completed each course. Walking speed and energy expenditure of the males were found to be significantly greater (p<0.05) than those of the females over all terrains (blacktop road, 1.6 km; dirt road, 1.8 km; light brush, 1.4 km; and heavy brush, 1.3 km) and for each load carriage condition. Relative energy expenditures of the males and females for all conditions were very similar (p>0.05) and remarkably constant at a value close to 45% VO2max These data indicate that the voluntary hard work rate is dependent upon maximal aerobic power. The best predictor of speed for self-paced hard work of males and females for 1 to 2 hours in duration appears to be based on 45% of maximal aerobic power.

15. Gehlsen GM & Dill DB (1977): Comparative performance of men and women in grade walking. Hum.Biol. 49, 381-388.

In various studies of the energy expended by males and females in level and grade walking some report females require less energy per kg of body weight than males, but others report equality of the sexes in this respect. In this study the possible influences on energy cost of differences in age or in height or in weight were eliminated. Twelve males and twelve females were selected to yield two groups having the same means of age, height and weight. Despite these uniformities, there were significant differences in that females had longer legs and lower oxygen consumption when resting and when walking at 80 meters per minute on a 7% grade. The difference between males and females in oxygen consumption in the grade walk was only 3.6%, this was accounted for almost entirely by the females' lower resting energy consumption. After subtracting the resting oxygen consumptions from the oxygen consumptions in the grade walk, the net values in liters per minute were 1.20 for females and 1.22 for males: not significantly different.

16. Geissler CA, Dzumbira TM & Noor Ml (1986): Validation of a field technique for the measurement of energy expenditure: factorial method versus continuous respirometry. Am.J.Clin.Nutr. 44, 596-602.

The field technique for measuring daily energy expenditure, using activity diary plus short-term indirect calorimetry, was validated with a room respirometer. Eleven male and 14 female subjects spent 24-h periods in the respirometer and kept an activity diary to the nearest minute. Subsequently, the energy cost of the recorded activities was measured in duplicate, and 24-h expenditure was calculated. Over the 42 24-h measurements the mean value by the factorial field method was within 1% of that from continuous indirect calorimetry. However, the error in individual daily expenditure ranged from -17% to +25%. Correction of the error involved in using calculated BMR for the cost of sleeping resulted in a 5% mean underestimation of the daily value. The factorial method is, therefore, too inaccurate for the estimation of individual daily expenditures but provides a close estimate of the true energy expenditure for population groups.

17. Hagan RD, Strathman T. Strathman L & Gettman LR (1980): Oxygen uptake and energy expenditure during horizontal treadmill running. .J.Appl.Physiol 49, 571-575.

The purpose of this investigation was to compare linear and curvilinear regression equations relating oxygen uptake and energy expenditure to running velocity and to examine the effects of age, sex, and maximal aerobic power on these relations in well-conditioned male and female runners. One-variable linear equations that use running velocity as the independent variable for predicting oxygen uptake and energy expenditure and coefficients of determination (r2) of 0.86 and 0.897, respectively. Two-variable linear equations that use body mass and velocity as independent variables had r2 values of 0.895 and 0.901 for the same relation. Age, sex, and maximal aerobic power did not influence the relations between oxygen uptake, energy expenditure, and running velocity. Stepwise regression indicated that the two-variable linear equations had the highest r2 values suggesting that between the running velocities of 8.8 and 16.9 km.h-1 these equations best express the relation of oxygen uptake and energy expenditure to running velocity.

18. Hagerman FC, Lawrence RA & Mansfield MC (1988): A comparison of energy expenditure during rowing and cycling ergometry. Med.Sci.Sport Exerc. 20, 479-488.

Department of Zoological and Biomedical Sciences, Ohio University, Athens 45701. Metabolic and cardiorespiratory responses of healthy adults were compared at similar incremental power outputs during a variable-resistance rowing exercise and a fixed-resistance cycle ergometer exercise. Repeated measurements of power (watts), VEBTPS, VO2 STPD, and HR were obtained on 60 men and 47 women ranging in age from 20 to 74 yr. Average maximal power output for the men was significantly higher (P less than 0.05) for cycling than rowing: 207 +/- 5.2 W vs 195 +/58 W (mean +/- SE:). A similar difference was also observed for women favoring cycling: 135 +/4.1 W vs 126 +/- 4.9 W (mean +/- SE). VEBTPS, VO2 STPD, and HR were significantly higher at all power increments during the rowing graded exercise test (RGXT) when compared with the same exercise intensity during the cycle graded exercise test (CGXT). Consistent linearity was found between VEBTPS and VO2 STPD and between HR and VO2 STPD for both exercises. The linear relationship between VEBTPS and VO2 STPD for men during RGXT was r = 0.976, P less than 0.001, slope = 44.6 +/- 1.03, and for women during RGXT it was r = 0.990, P less than 0.001, slope = 19.6 +/- 0.36. The relationship between HR and VO2 STPD for men during rowing was r = 0.989, P less than 0.001, slope = 29.1 +/- 0.76, and for women during rowing it was r = 0.971, P less than 0.001, slope = 35.7 +/- 0.89. The linear relationship between VEBTPS and VO2 STPD for men during CGXT was r = 0.991, P less than 0.001, slope = 31.1 +/- ().98, and for women it was r = 0.959, P less than 0.991, slope = 29.6 +/- 0.87. The relationship between HR and VO2 STPD for men during CGXT was r = 0.997, P less than 0.001, slope - 28.1 +/- 0.83, and for women it was r = 0.990, R less than 0.001, slope = 35.9 +/- 0.96. Results indicated that energy costs for rowing ergometry were significantly higher than cycle ergometry at all comparative power outputs including maximum levels. It was concluded that rowing ergometry could be an effective alternative activity for physical fitness and exercise rehabilitation programs.

19. Haymes EM & Byrnes WC (1993): Walking and running energy expenditure estimated by Caltrac and indirect calorimetry. Med.Sci.Sport Exerc. 25, 1365-1369.

The purpose of this study was to examine the accuracy of the Caltrac personal activity computer during walking and running. Ten women and 10 men walked at speeds of 2-5 mph and ran at speeds of 4-8 mph on a horizontal treadmill. Two Caltrac monitors were attached over opposite hips: one programmed to give caloric expenditure and the other to give Caltrac counts. Oxygen uptake was measured simultaneously. Significant correlations were found during walking between Caltrac estimated and actual expenditure (r=0.91) and between activity counts and net exercise (r=0.87). However, the Caltrac significantly overestimated energy cost during horizontal walking at speeds above 2 mph. Although there was a significant correlation between Caltrac estimated and actual expenditure during running (r=0.71), the correlation between Caltrac counts and net exercise was not significant (r=.29). There was no significant increase in Caltrac kcal or counts with increased running speed between 5 and 8 mph. It is concluded that the Caltrac is a valid indicator of physical activity during walking, but does not adequately discriminate between running speeds of 5-8 mph.

20. Holewijn M, Heus R & Wammes LJA (1992): Physiological strain due to load carrying in heavy footwear. Eur.J.Appl.Physiol 65,129-134.

TNO Institute for Perception, Thermal Physiology Research Group, Soesterberg, The Netherlands. To determine the effects of wearing heavy footwear on physiological responses five male and five female subjects were measured while walking on a treadmill (4, 5.25, and 6.5 km.h1) with different external loads (barefooted, combat boots, and waist pack). While walking without an external load the oxygen uptake, as a percentage of maximal oxygen uptake (%VO2max) of the men increased from 25% VO2max at 4 km.h-1 to 31% VO2max at 5.25 km.h-1 and to 42% VO2max at 6.5 km.h-1. The women had a significantly higher oxygen uptake of 30%, 40%, and 55% VO2max, respectively. In the most strenuous condition, walking at 6.5 km.h-1 with combat boots and waist pack (12 kg), the oxygen uptake for the men and women amounted to 53% and 75% VO2max respectively. The heart rate showed a similar response to the oxygen uptake, the women having a heart rate which was 15-40 beats.min-1 higher than that of the men, depending on the experimental condition. The perceived exertion was shown to be greatly dependent on the oxygen uptake. From the results a regression formula was calculated predicting the oxygen uptake depending on the mass of the footwear, walking speed and body mass. It was concluded that the mass of footwear resulted in an increase in the energy expenditure which was a factor 1.9-4.7 times greater than that of a kilogram of body mass, depending on sex and walking speed.

21. Holmer I (1972): Oxygen uptake during swimming in man. .J.Appl.Physiol 33, 502-509.

It is possible to set the water flow rate with great accuracy in a recently constructed swimming flume, i.e., a kind of swimming "treadmill". Oxygen uptake, heart rate, and blood lactate concentrations were measured in three female and six male adult subject, with varying proficiency in swimming, while subjects swam three styles at different speeds. The same determinations were made during exercise on a Krogh bicycle ergometer and on a treadmill. The same determinations were made in 12 girl swimmers, 13-18 years old, but only during maximal running and maximal swimming. Minimal oxygen uptake during floating in a vertical position in nine subjects varied from 0.9 to 2.0 I.min-1. At a given swimming speed the trained swimmers were able to swim with a much lower oxygen uptake than subjects who were not trained swimmers. At a given oxygen uptake trained swimmers also swam much faster than the untrained swimmers. The front crawl proved to be the most economical style, as is the case in competition swimming. The back crawl was somewhat less economical and the breaststroke was the least economical style. Maximal oxygen uptake, maximal pulmonary ventilation, and maximal heart rate were significantly lower in swimming than in running or cycling, respectively.

22. Howley ET & Glover ME (1974): The caloric costs of running and walking one mile for men and women. Med.Sci.Sport Exerc. 6, 235-237.

Our purpose was to resolve the disagreement as to the number of calories expended per unit distance for walking and running. The caloric costs of walking and running one mile on a treadmill were calculated for eight men and eight women. The subjects walked at a speed of 82 +3 m/min (X+- SD) and ran at a speed that was regarded subjectively as comfortable. The average speed at which the mile was run was 195 +- 25 m/min for men and 137 +- 4 m/min for women. The average R measured during the walk was 0.86 and during the run 0.96. The gross caloric cost of walking was 1.08 +- 0.06 kcal/kg per mile for men and 1.15 +-0.08 kcal/kg per mile for women, and the cost of running was 1.57 +- 0.09 kcal/kg per mile for men and 1.73 +0.09 kcal/kg per mile for women. The running required significantly more kcal/kg per mile than walking (P<0.001) and the women used significantly more calories for both running and walking compared to the men (P<0.01). The net caloric cost of walking was 0.76 +- 0.07 kcal/kg per mile for men and 0.83 +- 0.08 kcal/kg per mile for women, and the cost of running was 1.43 +-0.08 kcal/kg per mile for men and 1.53 +- 0.09 kcal/kg per mile for women. The difference between the run and walk was highly significant (P<0.001) and the women used significantly more calories than men for both activities (P<0.05). Possible reasons for the small but statistically significant difference between men and women are discussed. It was concluded that running a given distance required more calories than walking the same distance.

23. Johnson BL, Stromme SB, Adamczyk JW & Tennoe KO (1977): Comparison of oxygen uptake and heart rate during exercises on land and in water. Phys. Ther. 57, 273-278.

Oxygen comsumption and heart rate response during identical calisthenic-type exercises performed on land and in the water were compared in eight subjects. Both the heart rate and the oxygen uptake were greater during exercises in water. Although gravity is the primary resistance to movement on land, viscosity friction and turbulence are dominant resistive factors in the water. The results of this study indicate that the latter two factors provide a greater load during exercise than the resistance of gravity in land exercises. At a moderate rhythm of leg exercises, oxygen consumption increased about ten times over resting values in the water for :men subjects and about seven times for women. Arm exercise performed in the water require less energy than leg exercises in water, but arm exercises require significantly more oxygen when performed in water than the same exercises performed on land.

24. Katch VL, Villanacci JF & Sady SP (1981): Energy cost of rebound-running. Res.Q.Exerc.Sport, 52, 269-272.

The purpose of this study was to examine the energy cost and heart rate response of rebound-running on a mini trampoline and to make comparisons with other forms of aerobic exercise. Twelve volunteers were selected who varied in age, sex, weight and height. Oxygen consumption was measured in steady-state exercise conditions by open circuit respirometry. Subjects breathed through a Collins triple J respiratory valve into metereological balloons and the contents were analysed immediately. Gas analyzers were calibrated before and after each test. Oxygen uptake was calculated according to the method of Conzolazio et al (1963) and calorie expenditures calculated using the standard conversion for the calorific equivalent per liter of oxygen at a given respiratory exchange ratio, assuming steady-rate exercise conditions. The average VO2 for men and women combined was 1.21 I.min-1, which places rebound-running in the "moderate" exercise category, and the average calorie expenditure was 0.0864 [not original abstract]

25. Kumar S (1984): The physiological cost of three different methods of lifting in sagittal and lateral planes. Ergonomics, 27, 425-433.

Twelve young adults (six males-mean age 24.1 years, mean weight 75.4 kg and mean height 176.6 cm- and six females- mean age 20 years, mean weight 59.8 kg and mean height 162.6 cm) lifted and lowered a weight of 10 kg from a height of 13.5 cm at three-quarters reach. The weight was lifted and lowered in the! sagittal 30° lateral and 60° lateral plane by stoop, squat and freestyle techniques six times per minute for a period of 4 min. and the subjects rested for a period of 10 min. The steady-state values of oxygen consumption during these activities were measured. The subjects also subjectively assessed the relative degree of tiresomeness of the tasks studied. The oxygen consumption for each of the techniques was significantly different from the others (p<0.01). The stoop method of lifting required the least amount of oxygen and had the lowest per-minute inspiratory ventilation volume. The squat method required the highest oxygen consumption and inspiratory ventilation volume. The plane of the activities did not have a statistically significant effect on the energy consumption. The squat method of lifting was subjectively rated most tiring, and free style least tiring of the three techniques studied.

26. Kurzer MS (1987): Effect of activity on the energy cost of sitting in men and women: implications for calorimeter studies. Hum.Nutr.Clin.Nutr. 41C, 403-407.

It is important that activities be carefully standardized during whole-body human calorimetry studies because differences in physical activity in the calorimeter between subjects may mask true metabolic differences or result in false differences. The purpose of this study was to quantify the extra heat losses that: may occur due to small body movements, which are not standardized while sitting in whole-body calorimetry activity programmes. Energy expenditure was measured in 17 men and women while sitting passively and sitting actively. The subjects sat in a chair in a whole-body calorimeter for a total of 4 hours. During the first hour the subjects sat and were allowed to read and listen to the radio while adapting to the calorimeter. During the second and fourth hour the subjects sat passively, and during the third hour they performed standardized arm and leg stretches every 6 minutes while remaining seated. A 31 % increase in total heat loss during active sitting was found. It is thus important that the manner of sitting be controlled in studies looking for an effect smaller than 15%.

27. Makalous SL, Araujo J & Thomas TR (1988): Energy expenditure during walking with hand weights. Physician Sportsmed. 16, 139-148.

Eleven obese adults (three men, eight women) performed three 30-minute walking sessions at 3.4 mph: normal walking, walking with increased arm movement, and walking with increased arm movement while holding hand weights. The purpose was to assess the additional energy expenditure induced by carrying hand weights. Walking with hand weights resulted in increased heart rate (127 vs 120 beats.min-1), increased VO2 (1.168 vs 1.086 L.min-1), and greater energy expenditure (171.5 vs 159.7 kcal) compared with normal walking. Fat use and recovery energy expenditures were similar in all exercise conditions. Increased arm movements while walking without weights resulted in no significant increases over normal walking. These results indicate that using hand weights increased the energy demands of walking, but only to a small degree.

28. Maughan RJ & Leiper JB (1983): Aerobic capacity and fractional utilisation of aerobic capacity in elite and non-elite male and female marathon runners. Eur.J.Appl.Physiol 52, 80-87. The physiology of marathon running has been extensively studied both in the laboratory and in the field, but these investigations have been confined to elite competitors. In the present study 28 competitors who took part in a marathon race (42.2 km) have been studied; 18 male subjects recorded times from 2 h 19 min 58 s to 4 h 53 min 23 s; 10 female subjects recorded times between 2 h 53 min 4 s and 5 h 16 min 1 s. Subjects visited the laboratory 2-3 weeks after the race and ran on a motor driven treadmill at a series of speeds and inclines; oxygen uptake VO2 was measured during running at average marathon racing pace. Maximum oxygen uptake VO2 max) was measured during uphill running. For both males (r = 0.88) and females (r = 0.63), linear relationships were found to exist between marathon performance and aerobic capacity. Similarly, the fraction of VO2 max which was sustained throughout the race was significantly correlated with performance for both male (r = 0.74) and female (r = 0.73) runners. The fastest runners were running at a speed requiring approximately 75% of VO2 maxi for the slowest runners, the work load corresponded to approximately 60% of VO2 max. Correction of these estimates for the additional effort involved in overcoming air resistance, and in running on uneven terrain will substantially increase the oxygen requirement for the faster runners, while having a much smaller effect on the work rate of the slowest competitors. Five minutes of treadmill running at average racing pace at zero gradient did not result in marked elevation of the blood lactate concentration in any of the subjects.

29. Mayhew JL, Piper FC & Etheridge GL (1979): Oxygen cost and energy requirement of running in trained and untrained males and females. J.Sports Med. 19, 39-44.

The oxygen cost and energy requirement of submaximal treadmill running was assessed on trained (n=1) males and trained (n=5) and untrained (n=6) females. Open circuit spirometry was used to determine each subject's oxygen consumption during the final 2 minutes of 5-minute runs at 135, 150, 165, and 180 m/mint Two-way ANOVA was used to determine differences across speeds and subjects. Submaximal VO2 (ml/kg/min) was not significantly different among the four groups. Trained subjects, however, showed slightly greater efficiency than their untrained counterparts (5%). The VO2-running speed relationships were linear for all groups. Regression slopes and intercepts were not significantly different. Untrained females expended significantly more relative energy (kcal/kg/km) than untrained males, but no more than the two trained groups. The reason for this was perhaps a combination of greater relative fat content and inefficient running mechanics of the untrained females.

30. Miller JF & Stamford BA (1987): Intensity and energy cost of weighted walking vs. running for men and women. J.Appl.Physiol. 62, 1497-1501.

The energy cost and intensity of exercise performed at 0% grade were determined for walking at 2, 3, and 4 mph, running at 5, 6, and 7 mph, and walking at 2, 3, and 4 mph with ankle and/or hand weights. Subjects were young moderately trained males (4) and females (3). The energy cost per kilogram of body weight was similar between sexes, and data were combined for among-treatment comparisons. Intensity of effort and energy cost per minute and per mile were increased when weight was added during walking and were increased more with hand weights compared with ankle weights regardless of speed. The average increase in 02 uptake ( .min-1.100 g-1 of added wt) was 0.8% for ankle, 1.3% for hand, and 0.9% for ankle and hand weights. Gross energy cost per mile during weighted walking (120-158 kcal/mile) was comparable to and in some cases exceeded that of running which was independent of speed (120-130 kcal/mile). During nonweighted walking, the energy cost (kcal/mile) was significantly greater at 4 mph compared with 2 and 3 mph which did not differ. The intensity of walking at 4 mph with ankle and hand weights was comparable to running at 5 mph.

31. Morrissey SJ, George CE & Ayoub MM (1985): Metabolic costs of stoopwalking and crawling. Appl.Ergon. 16, 99-102.

This paper is a study of the metabolic costs of crawling and stoopwalking as performed by trained male and female subjects. After training, male and female subjects crawled and stoopwalked at a range of task speeds and in task postures set at 100, 90, 80, 70 and 60% of each subject's erect stature. It was found that as the task posture became more stooped, or the task speed increased, there were marked increases in metabolic cost. Further analysis found these increases to be due to the task speed within a posture, rather than from the task posture. It was also found that in some task postures, the combination of speed and posture resulted in metabolic costs of performance which would be limiting in terms of non-fatigue task performance time.

32. Padilla S. Bourdin M, Barthelemy JC & Lacour JR (1992): Physiological correlates of middle-distance running performance. A comparative study between men and women. Eur.J.Appl. Physiol. 65, 561-566.

Centro Medicina Deportiva, Neudigonoza Amadeo Garcia Salazar S/U, Victoria-Gasteiz, Spain. To compare the relative contributions of their functional capacities to performance in relation to sex, two groups of middle-distance runners (24 men and 14 women) were selected on the basis of performances over 1500-m and 3000-m running races. To be selected for the study, the average running velocity (v) in relation to performances had to be superior to a percentage (90% for men and 88% for women) of the best French v achieved during the season by an athlete of the same sex. Maximal 02 consumption VO2max and energy cost of running (CR) were measured in the 2 months preceding the track season. This allowed us to calculate the maximal v that could be sustained under aerobic conditions, va,max. A v:va,max ratio derived from 1500-m to 3000-m races was used to calculate the maximal duration of a competitive race for which v = va,max (tva,max). In both groups va,max was correlated to v. The relationships calculated for each distance were similar in both sexes. The CR [0.179 (SD 0.010) x m-1 in the women versus 0.177 (SD 0.010) in the men] and tva,max [7.0 (SD 2.0) min versus 8.4 (SD 2.1)] also showed no difference. The relationships between VO2max and body mass (mb) calculated in the men and the women were different. At the same mb the women had a 10% lower CR than the men; their lower mb thus resulted in an identical CR. In both groups CR and VO2max were strongly correlated (r=0.74 and 0.75 respectively, P < 0.01), suggesting that a high level of VO2max could hardly be associated with a low CR. These relationships were different in the two groups (P < 0.05). At the same VO2max the men had a higher va,max than the women. Thus, the disparity in track performances between the two sexes could be attributed to VO2max and to VO2max/Cr relationships.

33. Ryschon TW & Stray-Gundersen J (1991): The effect of body position on the energy cost of cycling. Med.Sci.Sport Exerc. 23, 949-953.

Department of Internal Medicine, U.T. Southwestern Medical School, Dallas. Energy expenditure during bicycling on flat terrain depends predominantly on air resistance, which is a function of total frontal area (bicycle and rider), coefficient of drag, and air speed. Body position on the bicycle may affect energy expenditure by altering either frontal area or coefficient of drag. In this study, oxygen uptake (VO2) was measured for each of four body positions in 10 cyclists (8 males, 2 females, 24 +1-2 yr, 67.7 +/- 3.3 kg, VO2max = 65.8 +/- 1.5 while each bicycled up a 4% incline on a motor-driven treadmill (19.3 km.h- 1), thereby eliminating air resistance. Positions studied included: 1) seated, hands on brake hoods, cadence 80 rev.min-1; 2) seated, hands on dropped bar (drops), 80 rev.min-1; 3) standing, hands on brake hoods, 60 rev.min-1; and 4) seated, hands on brake hoods, 60 rev.min-1. Subjects rode their own bicycles, which were equipped with a common set of racing wheels. Energy expenditure, expressed as VO2 per unit combined weight, was not significantly different between drops and hoods positioning (30.2 +/- 0.6 vs 29.9 +/- 0.9 but was significantly greater for standing compared with seated cycling (31.7 +/- 0.4 vs 28.3 +/- 0.7, P < 0.01). These results indicate that body posture can affect energy expenditure during uphill bicycling through factors unrelated to air resistance.

34. Ryschon TW & Stray-Gundersen J (1993): The effect of tyre pressure on the economy of cycling. Ergonomics, 36, 661-666.

Department of Internal Medicine, University of Texas, Southwestern Medical School, Dallas. Cycling requires power generation to overcome gravity, air resistance, and rolling resistance. When rolling surface and rolling speed are constant for a given tyre, rolling resistance is determined by tyre inflation pressure and the combined weight (COO) of the bicycle and rider. In this study, the oxygen uptake per unit CW (VO2.CW-1) of seven trained bicycle racers (5 men, 2 women, 24 +/- 2 years) was measured while each cycled up a 4% incline at 19.3 km.h-1 and 75 revolutions.min-1 on a motor-driven treadmill, using randomly-ordered tyre pressures of 552, 690, 827, and 965 kPa. Subjects (55.8-78.4 kg) rode their racing bicycles equipped with the same set of sew-up tyres and wheels. VO2.CW-1 was averaged over the last 3 min of a 5 min ride at each pressure. A repeated measures analysis of variance was performed and significance set at p c 0.05. VO2.CW-1 ranged from 28.1 +/- 0.6 to 28.9 +/- 0.5 x min-1 and was not significantly different between tyre pressures. We conclude that differences in rolling resistance caused by varying tyre pressure between 552 and 965 kPa are too small to be detected physiologically.

35. Schiller WR, Long CL, Carlo M, Davis D & Blakemore WS (1978): Energy costs of physical therapy in normal subjects. Fed.Proc. 37, 581.

Physical therapy is commonly administered to hospitalized convalescing patients, however, the energy demands for these treatments are not well known. Certain patients with marginal exercise tolerance may not tolerate exercises with high caloric expenditures. To quantitate the caloric expenditure of commonly utilized modes of physical therapy, 10 normal control volunteers were studied. The energy cost of these activities was determined by means of indirect calorimetry. The 02 consumption and the CO2 production were measured at, 1) resting levels, 2) during arm lifting of a 5 lb weight at 12 times per minute, and, 3) while doing straight leg raising at 6 times per minute for 12 minutes. The caloric expenditure for males at rest was 0.6107 ± .053 kcal/min/m² while for females was 0.6205 i .07 kcal/min/m². The values for arm lifting were 0.8169 ± .096 kcal/min/m² and 0.8052 + .0813 kcal/min/m² for females. This represented a 34% increase over resting values for males and 30% increase for females. When straight leg raising was performed, the caloric expenditure was 0.7973 i .076 kcal/min/m² for males and 0.8294 ± .099 kcal/min/m² for females. This represented a 31% for male and a 34% for female over resting values. In summary, these preliminary data show the energy cost of both activities to be slightly above that expended during standing as determined by a previous study to be 0.749 ± 0.12 kcal/min/m²

36. Seliger V (1968): Energy metabolism in selected physical exercises. Int.Z.angew.Physiol. einschl. Arbeitsphysiol. 25,104-120.

The energy costs of 15 physical activities were examined in 275 subjects under training conditions of the particular activity. The sample contains usually 15 medium athletically developed persons at minimum. The energy metabolism was followed by indirect calorimetrical method, the heart rate was registered throughout the experimental telemetrically. The activities were divided into three groups, according to the time of duration. The results showed that the energy expenditure ranges were in A-group (duration 5 min and more) 0.08-0.26 kcal/min/kg, in B-group (1-3 min) 0.11-0.45 kcal/min/kg, and in C-group (1-30 see) 0.68-1.75 kcal per min/kg. The observed values of heart rate, pulmonary ventilation, and oxygen uptake are discussed. No correlation between the energy expnditure and the intensity of the motional activity, according to pedagogues' observation was found. The relationship to physiological function was with respect to motional activity on 1-5% significance level, especially in sports from groups A and B. A graph was constructed of the relationship of the intensity of metabolism, against duration of the activity. Three fields limited by parallel lines enables us to judge the real metabolic rate during the sports' activity of examined persons to functional development of his organismus.

37. Snyder AC, O'Hagan KP, Clifford PS, Hoffman MD & Foster C (1993): Exercise responses to in-line skating: comparisons to running and cycling. Int.J.Sports Med. 14, 38-42.

Department of Human Kinetics, University of Wisconsin-Milwaukee 53201. A comparison of the physiological responses to in-line skating with the more traditional modes of exercise training has not been reported. The purpose of this study was to examine the physiological responses to in-line skating compared with running and cycling. Nine trained volunteers (2 male, 7 female) performed 3-6 submaximal (30-90% VO2max workloads with each exercise mode. Oxygen uptake, heart rate and blood lactate were measured during each trial. Across the spectrum of oxygen uptakes studied, heart rate was higher with in-line skating than with cycling or running. At a lactate concentration of 4 mM oxygen uptake was less for in-line skating and cycling than for running. Therefore, while in-line skating may be an effective mode of aerobic exercise, the training adaptations for in-line skating at 4 mM lactate may not be as great as for running, and at a given HR may be less than for running and cycling.

38. Stauffer RW, McCarter M, Campbell JL & Wheeler LF, Jr. (1987): Comparison of metabolic responses of United States Military Academy men and women in acute military load bearing. Aviat.Space Environ.Med. 58, 1047-1056.

Exercise Science Laboratory, United States Military Academy, West Point, New York 10996. Twenty-four first year United States Military Academy (USMA) men and women were studied to compare metabolic response differences in seven horizontal walking velocities, under three military load bearing conditions. The treadmill protocol consisted of walking or jogging on a horizontal treadmill surface for 3-min intervals at velocities of 3, 3.5, 4, 4.5, 5, 5.5, and 6 mph. The three military load bearing conditions weighed 5, 12, and 20 kg. Metabolic measurements taken at each speed in each of the military load bearing conditions were: minute volume, tidal volume, respiratory rate, absolute and relative to body weight oxygen consumption, and respiratory quotient. Two three-way analyses of variance for repeated measures tests with main effects of gender, military load, and speed revealed that USMA men and women metabolically respond to different military load bearing conditions; they metabolically respond to different walking and jogging velocities under military load bearing conditions; and they have identifiable and quantifiable metabolic response differences to military load bearing. This study was designed to improve USMA physical and military training programs by providing information to equally and uniformly administer the USMA Doctrine of Comparable Training to men and women alike; and additionally to clarify the "...minimal essential adjustments...required because of physiological differences between male and female individuals ..." portion of Public Law 94106 providing for the admission of women to America's Service Academies .

39. Town GP, Sol N & Sinning WE (1980): The effect of rope skipping rate on energy expenditure of males and females. Med.Sci.Sport Exerc. 12, 295-298.

The purpose was to study the effects of skipping rate on energy expenditure and sex differences in response to rope skipping. Responses of 19 males and 11 females were measured while skipping for 5 min at 125, 135 and 145 skips.min-1. Expired air was routed through a hollow handle to collection bags to provide uninterrupted exercise. Values at the respective rates for the total sample were: VO2 (I.min-1) 2.70, 2.83, 2.85; VO2 ( 41.1, 42.0 42.5; HR (beats.min-1) 176, 177, 177; VE (I.min) 102.2, 103.5, 106.3; R 1.09, 1.07, 1.05; energy expenditure (kj.min-1) 58.6, 59.4, 60.3. Sex differences were found in that females had significantly lower VO2 both in l.min-1 and but higher HR values than males. Comparison of VO2 values of the females to VO2max values reported for females in the literature suggested that they may have been exercising close to their maximum. There were no differences in any of the values due to skipping rate nor was there interaction between sex and rate. Retrospective cinematographic analysis on two subjects suggested that the failure to find significant differences due to rate may be due to a decrease in vertical displacement resulting in a relatively constant work output as skipping rate increased. Average MET values at the different rates ranged from 11.7 to 12.5, which supported findings from other studies that rope skipping is very strenuous exercise.

40. Webb P. Saris WHM, Schoffelen PFM, van Ingen Schenau GJ & ten Hoor F (1988): The work of walking: a calorimetric study. Med.Sci.Sport Exerc. 20, 331-337.

Experiments were designed to test the traditional assumption that during level walking all the energy from oxidation of fuel appears as heat and no work is done. Work is force expressed through distance or energy transferred from man to the environment, but not as heat. While wearing a suit calorimeter in a respiration chamber, five women and five men walked for 70 to 90 min on a level treadmill at 2.5, 4.6 and 6.7 km.h-1 and pedalled a cycle ergometer for 70 to 90 min against a horizontal load. During cycling, energy from fuel matched heat loss plus the power measured by the ergometer. During walking, however, energy from fuel exceeded that which appeared as heat, meaning that work was done. The power increased with walking speed; values were 14, 29 and 63 W. which represented 11, 12, and 13% of the incremental cost of fuel above the resting level. Vertical and horizontal loads increased the fuel cost and heat loss off walking but did not alter the power output. This work energy did not re-appear as thermal energy during 18 h of recovery. The most likely explanation of the work done is in the inter-action between the foot and the ground, such as compressing the heel of the shoe and bending the sole. We conclude that work is done in level walking.