STUDIES ON ENERGY EXPENDITURE OF RICKSHAW PULLERS By SACHCHIDANANDA BANERJEE, KESHAB NARAYAN ACHARYA AND DHURJATI PROSAD CHATTOPADHYAY. From the Dep3rtment ojPhysiology, Presidency College, Calcutta ( Received on April, 6, 1959) INTRODUCTION Numerous studies have been made on the energy expenditure l;>y persons engaged in different types of physical labour. Walking, running, carrying 13.1:15, etc. were the main features of such occupations. Closely similar results of the, energy cost of "walking" at varying speeds were reported by Brezina and Kolmer (1912), Douglas and Haldane (1912), Benedict and Murschhauser (1915), Atzler and Herbst (1927), and Margeria (1938). It was reported that the energy cost of walking erect was least when compared with the stooping postures by Moss (1935) and by Bedford and Warner (1955). The exp~nditure of energy by men and women while walking was determined by Booyens and Keatings (1957). Ogasawara (1934) and Mugeria (1933) reported that the energy expenditure of walking and run· ning vary with speed and depend on the efficiency and training of the subjects. One of the classical studies on load carrying was ofBedale (1924), who herself was the subject of her experiment and carried weights in 8 diffe­ rent ways and found that the energy expenditure was minimal with the use of yoke across fle sh()ulders and maximum when carried on the hip under the arm. The energy expenditure of carrying loads were also reported by Glas>ow and Muller (1951), Dressel et. at. (1954) and by Das (1951). It was reported by Dressel (1954-) and by Lehman (1953) that there exist relatively little difference in using several types of wheel barrows on a smoothed road or on planks. The present investigation deals with the studies on the energy cost of different types of activities of the rickshaw pullers of this city, and their daily calorie expenditure. MATERIALS AND METHODS The subjects of the experiment were eleven rickshaw pullers of this city, of ages varying between 25 and 35 years. They were medically examined and found healthy. The "rickshaw" - is a common two wheeled vehicle with a sitting accom­ modation of tWo persons and drawn by man. The diary technique of Garry et. at. (1955) for recording the time spent in various activities during the 24 hours period, was not possible because the rickshaw pullers could not read or write. The average time spent in various Present address: Prof. ojPhysiology, Bikaner Medical College, Bikaner, Rajasthan. 148 ENERGY EXPENblTURE OF RICKSHAW PULLERS activities during the 24 hours period was recorded by int~rviewing the subjects. So the exact time-work record was not possible but a very approximate idea of their'usual routine work was 'obtained. The basal metabolic rate and the energy,cost of different activities which occupied the main featu!es of their occupations e.g. lying rest. sitting rest, standing rest, sitting' 'work, standing work, walking, plying rickshaw without and with one, two and three passengers repectivdy were determined. I Measurements of the energy' cost of various activities were made by the "Max·Plank - Institute Fur Arbeitzphysiologie" respirometer (Kofranyi and Micha:lis, 1940; Muller and Franz, 1952). The respirometer was calibrat~d according to the method of Durnin (1955). .Douglas bag was used only during the determination of basal metabolic rate. The gas samples, from the rubber bladder of the Max Plank respirometer, and from the Douglas bag were collected over mercury in Bailey's bottles. Analysis of the gas samples were done in duplicate using ~aldane-H~nderson.Bailey's gas analysis apparatus. Energy cost of each activity was caTculated from the oxygen con­ sumption at N.T.P. after introducing thenecessiiry corrections for the diffu­ sion of gases from the rubber bladder a~d from the percentage of .aliqouts of gases collected in ,the rubber bla'dder t~king the ,calorie equivalent of one litre of oxygen at the particular R.Q. from the table of Lusk (1924). , Surface area was calculated according to the formulae of Du Bois and Du Bois (1916) and of Banerjee and Sen (1955}. RESULTS . The age, height, weight and surface area of the subjects are given in Table I. The age varied between 25 and 54 years, height between 149'3 and 171'3 cms., weight between.38·56 and 51'61 kg., and surface area when measured by the formula of Banerjee and Sen (1955) varied between 1'329 and 1'741 m 2 and between 1'278 and 1'675 m2 when me~ured by Du' Bojs and Du Bois (1916) height weight formula. .. The energy cost of lyirig rest, sitting rest; standing rest, sitting wor,king, standingi~orking, walking and the B.M.It.' eXl?ressed as Cals/min, Cal/kg/hr. and Calsjm~/hr.. (according to Du Bois arid Du Bois (1916) and Bane'rjee and Sen (1955) are given in Tables 2, 3, 4 and 5. The energy c~~t' of walk:i~g 'and plyi~g of ~icksha~ 'without and with, I. 2, and 3 passengers expressed as:' ·Calsjkilometer/hr., Calsjkilometer/hr/m2 body surface accor-ding to Du Bois and Du Bois (1915), Baqerjee and Sen (1955) andCalsjkilometer/kg body weight are shown in Tables 6, 7, 8, 'and 9, The average time spent on each activi;y and 'the respective energy expenditure during the 24 lirs. period are given in Table 10. TABLE 2 .... CJo Energy cost of different activities (Cals/min). 0 Subjects. B.M.R. Lying rest Sitting rest Standing rest Sitting work Standing work Walking. B. N. G. 0.822 0.841 0.901 1.124 2.410 2.207 2.566 zto! M.C.R. 0.881 0.894 0.922 0.923 2.379 3336 2.484 !'l :0 (;) S. C. A. 0.906 0.961 1.012 1.122 2.176 2.323 2.319 >< to! ~ M.R. 0.735 0.815 1.028 1.973 2.198 2.486 "0 0.793 to! Z tl S. S. 0.832 0.855 0.993 1.. 183 2.670 2.198 2.920 ~ c: :0 T.M. 0.757 0.809 0.872 1.034 1.560 1.916 2.092 trl 0.., ]. S. 0.962 1.086 1.141 1.193 2.271 2.635 2. 262 :0 0 D.N.S. :0: 0.701 0.813 0.881 1.194 2.323 2.484 2.917 en =;l> A. S. 0.807 0.821 0.872 0.891 1.668 2.024 2.715 :;: "0 R. S. S. c: 0.898 0.959 1.030 1.265 1.734 2.007 3.029 t"' r-' M H. K. S. 0.974- 1.007 1.277 1.396 1.703 2.326 3.012 :0 • '" Mean 0843 0.894 0.974 1.123 2.079 2.335 2.630 S.D. 0.087 0.095 0.131 0.131 0.351 0.382 0.312 ±S. E. ±0.026 ±0.029 ±0.039 ±0.039 ±0.106 ±0.115 ±0.094 \ , TABLE 3 Energy cost of different activitIes (Cals/kg/hr). Subjects. B. M. R:. Lying rest Sitting rest Standing r~st Sitting work- Standing work Walking. B.N. G. 1.012 1.035 1.109 1.384 2.967 2.717 3.282 1.195 1.213 1.251 1.252 3.227 4.567 3.371 M.C.R. I:Il >z S. C. A. 1.317 1.397 1.471 1.631 3.163 3.378 3.370 t'l ..... "t'l M.R. 0.972 1.049 1.077 1.360 2.610 2.907 3.290 J'l > 1.230 1.466 3.309 (') S. S. 1.031 1.060 2.724 3.618 :I: >~ T.M. 1.178 1.259 1.'35 7 1.609 2.428 2'982 3.254 -< > J. S. 1.074 ).213 1.274 1.331 2.536 2.942 2.524 >z 0 1.190 1.612 3.136 (') D.N.S. 0.946 1.097 3.352 3.977 :I: ~ 1.220 1.241 1.318 1.347 2.523 2.059 "'i A. S. 4.104 0 'tI > R. S. S. 0.974 1.040 1.117 1.372 1.879 2.176 3.284 0 :I: >< 1.014 1.048 1.329 1.454 1.774 2.423 > RK.S. 3.137 >< Mean 1.085 1.150 1.248 1.437 2.687 3.020 3.383' S.D. 0.115 0.117 0.114 0.134 0.501 0.593 0.400 ±O.035 ±0.035 ±0.035 ±0.04 ±0.151 ±0.179 ±O.l21 ±. S. E. -~ TABLE 4. (Jl Energy cost of different activities (Cals/m2 body.surface/hr) , • t-:l Surface area calculated according to Banerjee and Sen (1955) : fiu~ects. B. M. R. Lying rest S,itting rest Standing rest Sitting work Standing work Walking B.N. G. 31.82 34.88 43.52 93.33 85.49 103.20 M ,. 32.56 -z ~ M 1 " \I:l M.C.R. 134.40 99.19 (') 35.17 35.69 36.81 36.84 94.95 ><: I. r M S. C. A. 38.09 40.40 42.54 47.17 91.47 97.68 97.45 >: 'tl 'Mz M.R. 29.07 31.36 32.23 40.66 78.05 86.94 98,35 tl ::1 c::: S. S. 32.22 33.10 38.44 45.80 103AO 85.09 113.1 0 \I:l , M 0 T.M. 34.18 36.54 59.38 46.69 70.44 86.54 94.43 "l I ' q\I:l ]. S. 34.88 39.38 41.37 43.25 82.35 95.54 81.98 :0:: en ':1: D: N.