SAE TECHNICAL . tPAPER SERIES 911461

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Upper Body Exercise: Physiology and TrainingApplication for Human Presence in Space

Michael N. Sawka and Kent B. PandolfU.S. Army Research Institute of Environmental Medicine

Natick, MA

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The Engineering Society 21st International Conference onFor Advancing Mobility Environmental SystemsLand Sea Air and Space,, San Francisco, California

IN T E R N A T IO N A L July 15-18, 1991

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911461

Upper Body Exercise: Physiology andTraining Application for Human Presence in

SpaceMichael N. Sawka and Kent B. Pandolf

U.S. Army Research Institute of Environmental MedicineNatick, MA

ABSTRACT INTRODUCTION

Space physiologists have an interest in upper Upper body exercise provides many workbody exercise since in the weightless state astro- performance and physiological problems that arenauts do a substantial amount of work with their not evident during physical execise performedarms and hands. Upper body exercise elicits a with the legs (1)*. Space physiologists have anpeak oxygen uptake approximately 70% of that interest in upper body exercise, since in theobtained during lower body exercise; in addition, weightless state astronauts do a substantialupper body exercise requires a greater oxygen amount of work with their arms and hands anduptake at a given power output than lower body often use their lower body only for stabilizationexercise. Therefore, when performing exercise at (2,3,4). When aboard the spacecraft and duringa given power output, both the absolute and extravehicular activities (EVA), astronauts performrelative (% of peak Vo,) exercise intensity is mission related tasks that require upper bodygreater during upper body exercise. Although exercise for periods of three to six hours at meancardiac output responses for a given oxygen metabolic rates of 260 watts and peak metabolicuptake are similar, the heart rate, blood pressure rates of 625 watts (3,4). Shuttle astronauts haveand total peripheral resistance responses are reported that local fatigue of the upper bodygreater, and the stroke volume responses are skeletal muscles has limited their ability to performlower at a given oxygen uptake during upper than EVA (3). As noted by Convertino (3), excessivelower body exercise. Body temperature responses muscular fatigue should not be surprising at theseto both exercise types are similar, but the temper- modest metabolic rates as they likely representatures are achieved by different heat exchange "heavy" relative intensities for the upper bodymechanisms. During upper body exercise, there muscle groups where they only represent "light"is a greater reliance on torso dry heat loss for relative intensities for the lower body muscletemperature regulation. Exercise training pro- groups.grams can improve aerobic exercise capabilities The purposes of this paper are to discuss thefor the upper body, but there are minimal cross- physiological responses and control mechanismstraining benefits between the arms and legs. for upper body exercise, and to briefly discussSpace physiologists and engineers in the manned their application to the manned space program.space program should consider the unique physi- Upper body exercise has direct application toology associated with upper body exercise for: (a) achieving a sustained human presence in spaceassuring that astronauts are prepared to perform because: (a) astronauts must have sufficientmission related tasks; (b) developing effective physical fitness to perform mission related tasks ofexercise countermeasures programs; and (c)engineering of adequate life support systems. Numbers in parentheses designate references at end of

paper.

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which require use of the upper body muscle consistently lower during arm-crank than leg-cyclegroups; (b) exercise countermeasures for micro- exercise. Arm-crank exercise values range fromgravity environments must focus on maintenance 36% to 89% with a mean of 73% of leg-cycleof upper body work capabilities; and (c) the engi- exercise values. The investigations of Cerretelli etneering of astronaut life support systems, such as al. (18), Seals and Mullin (26), as well as Vrijensmicroclimate cooling systems for EVA, must et al. (13) indicate that individuals who train the7raccommodate the unique physiological adjust- upper body muscle groups can achieve arm-crankments associated with upper body exercise. values approaching 90% of their leg-cycle exercise

peak oxygen uptake values, whereas, sedentaryPHYSIOLOGICAL RESPONSES individuals may achieve only approximately 60%.

Generally, strong correlation coefficients (r=0.70 toAEROBIC METABOLISM - Figure 1 presents 0.94) have been reported (see Figure 3) for peak

a comparison of submaximal and peak oxygen oxygen uptake responses between upper anduptake responses for arm-crank and leg-cycle lower body exercise (15,20,29,30). A few investi-exercise (5). A greater oxygen uptake is elicited gators, however, have reported weaker relation-by arm-crank than leg-cycle exercise performed at ships (r=0.30 to 0.60) between these exercisethe same submaximal power output (5-13). types (31,32).Increased requirements for muscular stabilization The relatively smaller skeletal muscle massof the torso (9,10,14,15), a greater isometric involved during upper body exercise likely contrib-exercise component (1,5,6,16), as well as differ- utes to the reduced peak oxygen uptake valuesences in skeletal muscle recruitment patterns (1) compared to lower body exercise. Although thehave been suggested as responsible for the smaller skeletal muscle mass limits peak oxygenrelatively high oxygen uptake during submaximal uptake by its smaller oxidative capacity andarm-crank exercise. reduced ability to generate tension, the role of

Toner et al. (10) conducted experiments which muscle mass in accounting for individual differenc-provide insight into the physiological factors es of peak oxygen uptake during arm-crankresponsible for the relatively high oxygen uptake exercise remains unresolved (20,30,33). Armelicited by submaximal arm-crank exercise. volume measurements may (33) or may notCombined arm and leg exercise was performed (20,30) account for individual differences in peakwhere the distribution of a given power output oxygen uptake during arm-crank exercise. Never-(P0) was varied between arms and legs (20,40 theless, arm volume measurements provide a poorand 60% arm PO/toial PO), and these results estimate of the skeletal musculature employedwere contrasted with exercise performed with only during arm-crank exercise because the chest,arm-crank and only leg cycle. Figure 2 presents back and shoulder muscle groups are not includ-the results from experiments performed at 76 W ed.and 109 W (10). During the 76 W experiments, Upper body muscle groups are relativelyoxygen uptake increased linearly with increasing weaker than lower body muscle groups (34). Inpercent arm values; but during the 109 W experi- theory, muscular strength could influence upperments, oxygen uptake response could best be body performance by enabling stronger individualsdescribed by a power function. These investiga- to achieve higher levels of cardiorespiratory stresstors speculated that muscular stabilization of the prior to local fatigue and exercise termination.torso accounted for the linear increase in oxygen Sawka et al. (30) reported non-significant correla-uptake with increased arm participation during the tion coefficients between peak oxygen uptake for76 W experiments. A second unmeasured exer- arm-crank exercise and grip strength or isokineticcise component, believed to be excessive body elbow extension (30°/s) strength. Likewise, Falkelmovement, was suggested to account for the et al. (20) found grip strength as well as isokineticcurvilinear increase in oxygen uptake at the higher (30 and 1800/s) elbow flexor and extensor strengthpower output experiments, values had nominal relationships with peak oxygen

Table 1 presents a comparison of physiological uptake and endurance time for arm-crank exer-responses to maximal effort , .,rank and leg- cise.cycle exercise (5,12-28). Peak oxygen uptake is CARDIOVASCULAR - Cardiac output respon-

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ses at a given submaximal oxygen uptake are This could result in intramuscular tension thatsimilar, for arm-crank and leg-cycle exercise exceeds perfusion pressure and thereby effectively(6,11,14,16,23,35,36). Although upper and lower decrease the vascular cross-sectional area per-body exercise elicit a similar cardiac output, "ie fused (43,44). In cat fast- and slow-twitch mus-hemodynamics are quite different. According to cles, intramuscular pressure exceeds perfusionPoiseuille's equation, flow or 0 is the quotient of pressure at tensions above 50% of maximal (43).driving pressure (P) divided by resistance to flow Since 15%-20% of the quadriceps muscles' maxi-(R). By transposition, R equals P divided by 0; mal isometric tension is used during maximal effortand P equals the product of Q and R. Examina- leg-cycle exercise (40), it seems reasonable thattion of Figure 4 indicates that blood pressure is upper body exercise might generate sufficienthigher during arm-crank than leg-cycle exercise at intramuscular tension to mechanically increasea given oxygen uptake. If P is higher, then R peripheral resistance within the exercising arms.would be proportionally higher to elicit the same 0 Although cardiac output is the same duringduring upper than lower body exercise. Numerous submaximal arm-crank and leg-cycle exercise, it isinvestigators report higher systolic (9,16,37-39), achieved by marked differences in heart rate anddiastolic (9,16,36,37) and aortic (6) blood pres- stroke volume relationships (see Figure 4). Inves-sures during arm-crank than leg-cycle exercise. tigators consistently report a higher heart rate andSimilarly, total peripheral resistance is generally lower stroke volume at a given submaximal oxy-reported to be higher during arm-crank exercise gen uptake during arm-crank than leg-cycle exer-(6,9), although Miles etal. (36) reported no differ- cise (6,9,11,14,16). The elevated heart rateence between the exercise types. probably reflects a greater sympathetic stimulation

Based on Poiseuille's equation, a greater total during arm-crank exercise (1). This increasedperipheral resistance must account for the elevat- sympathetic stimulation should improve myocardialed blood pressure response during arm-crank contractility; however, similar values of contractilityexercise, since 0 is equal to that obtained during indices are reported during both exercise typesleg-cyc!e exercise. Vessel radius and blood (36). An increasec; myocardial contractility mayviscosity are the primary factors influencing R, and not be detected during arm-crank exercise be-both factors probably contribute to the greater total cause of differences in cardiac filling or pre-load.peripheral resistance during arm-crank exercise. During upper body exercise, reduced skeletalA smaller skeletal muscle mass is available for muscle pump activity might transiently fail toarm-crank than leg-cycle exercise; therefore, the facilitate venous return and decrease the ventricu-vascular cross-sectional area is smaller even lar end-diastolic volume (40). Therefore, a re-during maximal vasodilation. The smaller vascular duced pre-load will have the myocardium contract-cross-sectional areas being perfused by the same ing on a less efficient portion of the ventricular6 will result in a greater R. Also, an increased function curve. Under such conditions, an in-sympathetic response to arm-crank exercise will creased sympathetic stimulation (positive inotropicresult in the non-exercising muscles having a effect) would be needed to obtain similar contrac-greater vasoconstrictor tone and contribute to an tility values during upper body as compared toincr9ased R (40). Several investigators (19,41) lower body exercise. This reduced pre-loadreported that plasma catecholamine concentra- hypothesis may partially explain why stroke vol-tions are inversely related to the active skeletal ume does not increase (unlike lower body exer-muscle mass during submaximal exercise at a cise) markedly with arm-crank exercise intensitygiven oxygen uptake. Therefore, vasoconstrictor (6,9,11,35,45). Additionally, the increased after-drive is expected to be greater during arm-crank load reported for upper body exercise wouldthan leg-cycle exercise. impede stroke volume.

Total peripheral resistance may also increase TEMPERATURE REGULATION - There isbecause of greater mechanical compression of the debate as to whether upper body exercise resultsvasculature during upper body exercise. Exercise in different equilibrium levels of core temperatureperformed with a smaller skeletal muscle mass than those elicited by lower body exercise at themust develop a greater percentage of its maximal same metabolic rate (46). Several (47-49) investi-tension to produce a given power output (24,42). gators indicated that arm-crank exercise elicited

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different thermoregulatory responses and core amine concentrations are higher during sub-temperature values than lower body exercise. maximal exercise at a given oxygen uptake;Examination of those early studies, however, therefore, vasoconstrictor drive would be expectedsuggests that small sample size, technical prob- to be greater during upper than lower body exer-lems and inconsistent results make any conclu- cise (19,41).sions tenuous. The cardiovascular system may have greater

As previously discussed, maximal effort arm- difficulty in supporting the thermoregulatory systemcrank exercise elicits an oxygen uptake that is during upper than lower body exercise. Forapproximately 70% of that obtained during maxi- example, during upper body exercise the legs aremal effort leg-cycle exercise. It can be argued inactive, so there is less skeletal muscle pumpthat if core temperature elevations during exercise activity to facilitate venous return. If upper bodyare determined by relative intensity (with respect exercise were performed in the heat, the largeto the musculature employed) then arm-crank blood volume displaced in the cutaneous vascula-exercise would be expected to elicit a higher core ture combined with minimal skeletal muscle pumptemperature for a given metabolic rate than would activity could make it more difficult to maintainlower body exercise. There is also a different cardiac output. In addition, there is a greater totalmuscular source of metabolic heat during upper peripheral resistance and myocardial afterloadthan lower body exercise; as a result, tempera- during upper body exercise at a given oxygentures measured within a given body region may be uptake (52). Finally, there is a greater hemocon-different relative to other body regions. Therefore, centration at a given oxygen uptake during upperdifferent sites of core tempcrature, such as esoph- than lower body exercise (8,38). It is known thatageal or rectal, might provide disparate values, a reduced blood volume will result in less efficientFor example, blood warmed from leg muscular thermoregulatory responses during leg exerciseexercise might influence the rectal temperature to (53). As a result, the greater hemoconcentrationa greater degree than the esophageal tempera- might result in greater body heat storage duringture. The surface area-to-mass ratio of the arms upper than lower body exercise.is greater than that of the legs. A greater surface Table 2 provides a summary of the investiga-area-t-mass ratio for the exercising arms or limb tions which have examined the core temperaturecould facilitate heat loss and alter thermoregulato- and thermoregulatory responses to upper bodyry respunses during exercise. exercise (25,47,48,54-57). During the following

There are several neural factors that might paragraphs, an attempt will be made to explainmodify thermoregulatory responses to upper body some of the discrepancies between these investi-exercise. Robinson and colleagues (50) theorized ga,;ons.that thermal receptors located in skeletal muscle In 1947, Asmussen and Nielsen (47) studiedand in associated veins may provide afferent two subjects' core (rectal) temperature responsesinputs to the thermoregulatory centers in the brain, to arm-crank and leg-cycle exercise at the sameLikewise, mechanoreceptors and metaboreceptors metabolic rates. They found that after forty min-within the skeletal muscles might provide afferent utes of exercise, the elevation in rectal tempera-thermoregulatory information (48). Since upper ture was 0.280 C less during arm-crank than leg-body exercise employs a smaller skeletal muscle cycle exercise. The authors noted that the sub-mass than lower body exercise, a greater metabol- jects did not achieve steady-state rectal tempera-ic rate and heat production per unit of musle ture levels by forty minutes, but were unable tomust occur in order to perform exercise at a given exercise longer because of local fatigue. Asmus-oxygen uptake. Thermoregulatory afferent infor- sen and Nielsen (47) were concerned that rectalmation should therefore be somewhat quantitative- temperature values may have been spuriouslyly and qualitatively different using upper than lower high during leg-cycle exercise because of thebody exercise. This logic has led several investi- warm venous blood returning from the leg mus-gators to suggest that there is a different thermo- cles. They conducted additional experiments inregulatory setpoint (47,51) that results in higher which they measured stomach temperature. Inequiiibrium core temperature during upper than agreement with their rectal temperature date, thelower body exercise. Finally, plasma catechol- stomach temperature values were consistently

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lower during arm-crank than leg-cycle ergometer pared rectal temperature (10 cm) responsesexercise. Since both indices of core temperature between upper and lower body exercise. Sawkawere lower during arm-crank exercise, they con- et al. (55) measured rectal temperature responsescluded that upper body exercise results in a during arm crank and leg-cycle exercise in ninereduced thermoregulatory set-point than lower subjects at the same metabolic rate as well asbody exercise. relative intensity (% of peak Vo 2 for specific modes

In 1968, Nielsen (48) examined two subjects' of exercise). During the experiments with matchedcore (rectal and esophageal) temperature respons- metabolic rates, the subjects' steady state rectales to arm-crank and leg-cycle exercise over a temperatures and total body sweating rates wererange of metabolic rates. Rectal temperature the same for both exercise types. On the othervalues (mean of values obtained at four depths) hand, during the experiments with matched rela-were found to be lower (0.20 to 0.400 C) during tive intensities, the subjects' rectal temperaturesarm-crank than leg-cycle exercise. In contrast, the and total body sweating rates were lower during.esophageal temperature values were not different arm-crank than leg-cycle exercise. Pivarnik andbetween the two exercise types. Figure 5 pres- colleagues (57) measured eight subjects' rectalents the steady-state esophageal temperature temperature responses to arm-crank and leg-cycleresponses in relation to absolute metabolic rate exercise at the same metabolic rate in both a(watts) during arm-crank and leg-cycle exercise 22-C and 33°C environment. They found that the(48). In addition, the subjects' sweating rates and rectal temperature responses were the same forthermal conductances were not different between both modes of exercise. Young et al. (56) foundthe two modes of exercise. She concluded that that subjects had the same rectal temperaturethermoregulatory control during exercise was not responses for both arm-crank and leg-cycle exer-modified by the muscle groups employed. cise in a 380C environment while wearing a micro-

Subsequent investigators have found no climate cooling system over the torso. It seemsdifference in either tympanic (54) or esophageal clear that rectal temperatures measured at 10 cm(53) temperatures between upper and lower body are the same for both upper and lower bodyexercise performed at a given metabolic rate. exercise.These observations confirmed Nielsen's thesis that The question remains why the deep (>20 cm)exercise type does not modify the thermoregulato- rectal temperature measurements are systemati-ry control (48). Nielsen's data, however, raised cally lower during upper body exercise? For lowerthe possibility that rectal temperature might pro- body exercise, the rectal temperature is not influ-vide systematically low values for upper body enced by depth (greater than 5 cm), and theseexercise. This possibility was consistent with lower body exercise values are equivocal tosome indirect observations made by Nielsen and shallower (10 cm) rectal temperature measure-Nielsen in 1962 (49). These authors (49) found ments during upper body exercise at a giventhat during leg exercise esophageal temperature metabolic rate. The problem seems to be thatwas lower that rectal temperature, but that during deep rectal areas are not warmed as much duringarm exercise esophageal temperature was equal upper body exercise (48). For an average adult,to rectal temperature values. The investigators the rectum and anal canal length is approximatelymeasured rectal temperature at four depths (12, 12-16 cm (58); therefore, the deeper (20-27 cm)17, 22 and 27 cm) during either leg-cycle or arm- measurements were obtained well within thecrank exercise. They found that during leg-cycle sigmoid colon. The rectum receives its bloodexercise the measurement depth did not influence supply from the inferior mesenteric, as well Fsrectal temperature values, but that during arm- branches of the iliac and internal pudendal arter-crank exercise the deeper rectal measurements ies. The sigmoid colon receives its blood supply(22 and 27 cm)) tended to produce lower tempera- only from the inferior mesenteric artery. Duringture values. Therefore, rectal temperature mea- upper body exercise, the greater sympatheticsurements at a depth of 20 cm or greater may output should cause a greater constriction ofresult in spuriously low core temperature estimates splanchnic beds and result in reduced bloodduring upper body exercise. supply from the mesenteric artery. Perhaps this

Several investigators (55,56,57 ) have com- compensatory vasoregulation reduces the supply

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of warm blood more to the sigmoid colon than the compensatory heat loss depends upon the differ-rectum. Also, since the mucous membrane in the ential heat transfer coefficients which influencerectum is thicker and more vascular than in the tissue conductivity and mass transfer.colon (59); therefore, it should receive a richer Sawka and colleagues (25) attempted tosupply of warm blood during exercise. Finally, it determine if mode of exercise altered the controlis possible that the sigmoid colon area could be of thermoregulatory sweating. They found that theinfluenced more than the rectum by warmed sweating threshold and slope were not significantlyvenous blood from the legs during lower body different between arm-crank and leg-cycle exer-exercise (48,60); however, there is no anatomical cise. Therefore, local sweating rate (back) ap-evidence to support this notion. pears to be independent of the active skeletal

The preceding studies all examined core muscle mass and wholly dependent on the ther-temperature responses but did not attempt to mal drive. Previously, Tam et aL (51) suggestedquantitate the regional differences in evaporative that arm-crank exercise might elicit a non-thermaland dry heat exchange between upper and lower drive to sweating through increased sympatheticbody exercise. Sawka and colleagues (25) exam- activation. Their experiments, however, wereined the relative contribution of local evaporative, performed on only two subjects (one was a spinalradiative and convective heat exchange between cord injured subject) and only during arm-crankarm-crank and cycle exercise at the same meta- exercise.bolic rate. These experiments were conducted in The previous studies also indicate that differ-an 180C/78% relative humidity (rh) environment, ences in the surface area-to-mass ratio betweenwhich facilitated dry heat exchange, and in a the exercising arms and legs have nominal ther-350C/28% rh environment, which facilitated evapo- moregulatory effects in air. Water, however, hasrative heat loss. In both environments, esophage- a heat conduction approximately 25 times greateral temperatures were not different between exer- than still air. It seems that during cool-watercise types. Figure 6 illustrates the torso net immersion, exercise performed with the armsradiative energy flux values during exercise in the (relatively large surface area-to-mass ratio) andtwo environments. In each environment, these with the legs (relatively small surface area-to-massvalues increased over time for both modes of ratio) would be expected to have different heatexercise, with arm-crank exercise eliciting greater exchanges. Toner et aL (62) examined the ther-values than cycle exercise. Although this was a mal responses of subjects performing 45 minutesnew finding, it was not unexpected. During upper of arm-crank or leg-cycle exercise while immersedbody exercise, the muscles of the back torso in stirred water at 20, 26 and 330 C. Metabolic rateareas (i.e., latissimus dorsi, trapezius, infraspina- was not different between exercise types at eachtus) are employed to a greater extent than during water temperature. Rectal temperatures (10 cm)lower body exercise. Therefore, these skeletal were lower for arm-crank than leg-cycle exercise.muscle groups would generate and release a These lower core temperatures were supported bygreater metabolic heat that would be conducted both mean weighted skin temperature and meandirectly through the surrounding tissues to the weighted heat flow values; both of which wereoverlying skin (61). greater during arm-crank than leg-cycle exercise

These investigators found that torso and arm at each water temperature. These data indicateevaporative heat loss as well as arm dry heat that individuals are at a thermoregulatory disad-exchange were not different between exercise vantage (for hypothermia) when performing uppertypes in each environment (25). Leg dry heat loss body exercise in environments with a high convec-was greater during leg-cycle than. arm-crank tive heat transfer coefficient.exercise in the 180C environment; likewise, leg AEROBIC CROSS-TRAINING - Peak oxygenevaporative heat loss was greater during cycle uptake levels are dependent on central (cardiacthan arm-crank exercise in the 350C environment, output) and peripheral (ability of muscle cells toThese data indicate that to compensate for greater extract and utilize oxygen) components (63).torso dry heat loss during upper body exercise, Aerobic training adaptations pertaining to thelower body exercise elicits additional dry or evapo- enhanced myocardial contractility and increasedrative heat loss from the legs. The avenue for this cardiac hypertrophy would occur regardless of

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whether the upper or lower body muscle groups REFERENCESwere trained. Aerobic training adaptation pertain-ing to the peripheral components such as in- 1. Sawka, M.N. Physiology of upper bodycreased muscular capillarization and increased exercise. Exercise and Sport Sciences Reviews.vascular conductance as well as increased oxida- 14: 175-211, 1986.tive capacity would occur primarily in only the 2. Convertino, V.A. Physiological adaptationstrained skeletal muscle groups. As a result, it to weightlessness: Effects of exercise and workwould be expected that central component adapta- performance. Exercise and Sport Sciences Re-tions would provide some aerobic cross-training views 19:119-167, 81990.between the upper and lower body, but that the 3. Gazenko, O.G., V.I. Shumakov, L.J. Kaku-lack of peripheral component adaptations in the rin, V.E. Katkov, V.V. Chestukhin, V.M. Mikhailov,untrained limbs would limic the magnitude of A.Z. Troshin, and V.N. Nesvetov. Central circula-aerobic cross-training between the upper and tion and metabolism of the healthy man duringlower body. postural exposures and arm exercise in the head-

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Royce, and B. Saltin. Hemodynamic response toACKNOWLEDGEMENTS work with different muscle groups, sitting and

supine. J. Appl. Physiol. 22:61-70, 1967.The authors gratefully acknowledge Ms. 10. Toner, M.M., M.N. Sawka, L. Levine, and

Patricia DeMusis for preparing the manuscript. K.B. Pandolf. Cardiorespiratory responses toexercise distributed between the upper and lower

The views, opinions and findings in tnis report body. J. Appl. Physiol.54:1403-1407, 1983.are those of the authors and should not be con- 11. Toner, M.M., E.L. Glickman, and W.D.strued as an official Department of the Army McArdle. Cardiovascular adjustments to exerciseposition, policy or decision, unless so designated distributed between upper and lower body. Med.by other official documentation. Sci. Sports Exerc. 22:773-778, 1990.

12. Vokac, Z., H. Bell, E. Bautz-Holter, and K.Approved for public release; distribution is Rodahl. Oxygen uptake/heart rate relationship in

unlimited, leg and arm exercise, sitting and standing. J.Appl. Physiol. 39:54-59, 1975.

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13. Vrijens, J., P. Hoekstra, J. Bouckaert, and 26. Seals, D.R., and J.P. Mullin. Vo~max inP. Van Uytvanck. Effects of training on maximal variable type exercise among well-trained upperworking capacity and haemodynamic response body athletes. Res. Quart. Exerc. Sport 53:58-63,during arm and leg exercise in a group of pad- 1982.dlers. Eur. J. Appl. Physiol. 34:113-119, 1975. 27. Secher, N.H., N. Ruberg-Larsen, R.A.

14. Davies, C.T.M., and A.J. Sargeant. Binkhorst, and F. Bonde-Petersen. MaximalPhysiological responses to standardized arm work. oxygen uptake during arm cranking and combinedErgonomics 17:41-49, 1974. arm plus leg exercise. J. App. Physiol. 36:515-

15. Davis, J.A., P. Vodak, J.H. Wilmore, J. 518, 1974.Vodak, and P. Kurtz. Anaerobic threshold and 28. Vander, L.B., B.A. Franklin, D. Wrisley,maximal aerobic power for three modes of exer- and M. Rubenfire. Cardiorespiratory responses tocise. J. Appl. Physiol. 41:544-550, 1976. arm and leg ergometry in women. Physician

16. Astrand, P.-O., B. Ekblom, R. Messin, B. Sportsmed. 12:101-106, 1984.Saltin, and J. Stenberg. Intra-arterial blood pres- 29. Bar-Or, 0., and L.D. Zwiren. Maximalsure during exercise with different muscle groups. oxygen consumption test during arm exercise-J. Appl. Physiol. 20:253-256, 1965. reliability and validity. J. Appl. Physiol. 38:424-

17. Bergh, U., L.-L. Kanstrum, and B. Ekblom. 426, 1975.Maximal oxygen uptake during exercise with 30. Sawka, M.N., M.E. Foley, N.A. Pimental,various combinations of arm and leg work. J. and K.B. Pandolf. Physiological factors affectingAppl. Physiol. 41:191-196, 1976. upper body aerobic exercise. Ergonomics 26:639-

18. Ceretelli, P., D. Pendergast, W.C. Pagan- 646, 1983.elli, and D.W. Rennie. Effects of specific muscle 31. Bouchard, C., P. Godbout, J.-C. Mondor,training on Vo, on-response and early blood and C. Leblanc. Specificity of maximal aerobiclactate. J. Appl. Physiol. 47:761-769, 1979. power. Eur. J. Appl. Physio. 40:85-93, 1979.

19. Davies, C.T.M., J. Few, K.G. Foster, and 32. Franklin, B.A. Exercise testing, trainingA.J. Sargeant. Plasma catecholamine concentra- and arm ergometry. Sports Med. 2:100-119, 1985.tion during dynamic exercise involving different 33. Washburn, R.A., and D.R. Seals. Peakmuscle groups. Eur. J. Appl. Physiol. 32:195-206, oxygen uptake during arm cranking for men and1974. women. J. App. Physiol. 56:954-957, 1984.

20. Falkel, J.E., M.N. Sawka, L. Levine, N.A. 34. Falkel, J.E., M.N. Sawka, L. Levine, andPimental, and K.B. Pandolf. Upper body exercise K.B. Pandolf. Upper to lower body muscularperformance: comparison between women and strength and endurance ratios for women andmen. Ergonomics 29:145-154, 1986. men. Ergonomics 28:1661-1670, 1985.

21. Fardy, P.S., D. Webb, and H.K. Hellers- 35. Miles, D.S., M.N. Sawka, R.M. Glaser,tein. Benefits of arm exercise in cardiac rehabilita- S.W. Wilde, B.M. Doerr, and M.A.B. Frey. As-tion. Physician Sportsmed. 5:31-41, 1977. sessment of central hemodynamics during arm-

22. Pendergast, D., P. Cerretelli, and D.W. crank exercise. IEEE NAECON Record 442-448,Rennie. Aerobic and glycolytic metabolism in arm 1982.exercise. J. App. Physiol. 47:754-760, 1979. 36. Miles, D.S., M.N. Sawka, D.E. Hanpeter,

23. Reybrouck, T., G.F. Heigenhauser, and J.E. Foster, B.M. Doerr, and M.A.B. Frey. CentralJ.A. Faulkner. Limitations to maximum oxygen hemodynamics during progressive upper- anduptake in arm, leg, and combined arm-leg ergo- lower-body exercise and recovery. J. Appl. Phy-metry. J. Appl. Physiol. 38:774-779, 1975. sio. 57:366-370, 1984.

24. Sawka, M.N., M.E. Foley, N.A. Pimental, 37. Blomqvist, G., I. Astrand, and R. Messin.M.M. Toner, and K.B. Pandolf. Determination of Clinical, physiological, and ele.. . ;ardiographicmaximal aerobic power during upper-body exer- findings in patients with angina pectoris duringcise. J. Appl. Physio. 54:113-117, 1983. work in cold environments and during arm work.

25. Sawka, M.N., R.R. Gonzalez, L.L. Drolet, Acta Med. Scand. 178 (Suppl. 440):74-81, 1965.and K.B. Pandolf. Heat exchange during upper- 38. Miles, D.S., M.N. Sawka, R.M. Glaser,and lower-body exercise. J. Appl. Physiol. 57:- and J.S. Petrofsky. Plasma volume shifts during1050-1054, 1984. progressive arm and leg exercise. J. App/. Phy-

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siol. 54:491-495, 1983. 51. Tam, H.-S., R.C. Darling, H.-Y. Cheh, and39. Wahren, J., and S. Bygdeman. Onset of J.A. Downey. Sweating responses: a means of

angina pectoris in relation to circulatory adaptation evaluating the set-point theory during exercise. J.during arm and leg exercise. Circulation 44:432- Appl. Physiol. 45:451-458, 1978.441, 1971. 52. Miles, D.S., M.H. Cox, and J.P. Bomze.

40. Clausen, J.P. Circulatory adjustments to Cardiovascular responses to upper body exercisedynamic exercise and effect ci physical training in in normals and cardiac patients. Med. Sci. Sportsnormal subjects and in patients with coronary Exerc. 21:S126-S131, 1989.artery disease. Prog. Card. Dis. 18:459-495, 53. Sawka, M.N., R.P. Francesconi, A.J.1976. Young, and K.B. Pandolf. Influence of hydration

41. Hooker, S.P., C.L. Well-, M. Manore, S.A. level and body fluids on exercise performance inPhilip, and N. Martin. Differences in epinephrine the heat. J. Am. Med. Assoc. 252:1165-1169,and substrate responses between arm and leg 1984.exercise. Med. Sci. Sports Exerc. 22:779-784, 54. Davies, C.T.M., C. Barnes, and A.J.1990. Sargeant. Body temperature in exercise: effects

42. Simmons, R., and R.J. Shephard. Effects of acclimatization to heat and habituation to work.of physical conditioning upon the central and Int. Z. angew. Physiol 30:10-19, 1971.peripJheral circulatory response to arm work. Int. 55. Sawka, M.N., N.A. Pimental, and K.B.Z. angew Physiol. 30:73-84, 1971. Pandolf. Thermoregulatory responses to upper

43. Petrofsky, J.S., D. Hanpeter, and C.A. body exercise. Eur. J. App. Physiol. 52:230-234,Phillips. Intramuscular pressure during isometric 1984.exercise in fast and slow muscles of the cat. 56. Young, A.J., M.N. Sawka, Y. Epstein, B.Physiologist (abstract) 23:47, 1980. DeCristofano and K.B. Pandolf. Cooling different

44. Sawka, M.N., J.S. Petrofsky, and C.A. body surfaces during upper and lower body exer-Phillips. Energy cost of submaximal isometric cise. J. Appl. Physiol. 63:1218-1223, 1987.contractions in cat fast and slow twitch muscles. 57. Pivarnik, J.M., T.R. Grafner, and E.S.Pfluegers Arch. 390:164-168, 1981. Elkins. Metabolic, thermoregulatory and psycho-

45. Magel, J.R., W.D. McArdle, M. Toner, and physiological responses dufing arm and leg exer-D.J. Delio. Metabolic and cardiovascular adjust- cise. Med. Sci. Sports Exerc. 20:1-5, 1988.ment to arm training. J. Appl. Physiol. 45:75-79, 58. Moore, K.L. Clinically Oriented Anatomy.1978. J.N. Gardner-(Ed.) Baltimore: Williams and Wil-

46. Sawka, M.N., and W.A. Latzka. Tempera- kins, 1985.ture regulation during upper body exercise:able- 59. Gray, H. Anatomy of the Human Body.bodied and spinal cord injured. Med. Sci. Sports C.M. Goss (Ed.). Philadelphia: Lea and Febiger,Exerc. 21:$132-S140, 1989. 1973.

47. Asmussen, E., and M. Nielsen. The 60. Mead, J., and C.L. Bonmarito. Reliabilityregulation of the body-temperature during work of rectal temperatures as an index of internal bodyperformed with the arms and with the legs. Acta temperature. J. AppL Physio. 2:97-109, 1949.Physiol. Scand. 14:373-382, 1947. 61. Wade, C.E., and J.H. Veghte. Thermo-

48. Nielsen, B. Thermoregulatory responses graphic evaluation of the relative heat loss by areato arm work, leg work and intermittent leg work. in man after swimming. Aviat. Space Environ.Acta Physiol. Scand. 72:25-32, 1968. Med. 48:16-18, 1977.

49. Nielsen, B. and M. Nielsen. Body temper- 62. Toner, M.M., M.N. Sawka, and K.B.ature during work at different environmental Pandolf. Thermal response during arm and legtemperatures. Acta Physiol. Scand. 56:120-129, and combined arm-leg exercise in water. J. Appl.1962. Physio. 56:1355-1360, 1984.

50. Robinson, S., F.H. Meyer, J.L. Newton, 63. Neufer, P.D. The effects of detraining andC.H. Ts'ao, and L.O. Holgersen. Relations be- reduced training on the physiological adaptationstNeen sweating, cutaneous blood flow, and body to aerobic exercise training. Sports Med. 8:302-temperature in work. J. Appl. Physiol. 20:575-582, 321, 1989.1965. 64. Clausen, J.P., K. Klausen, B. Rasmussen

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and J. Trap-Jensen. Control and peripheral kayak and bicycle ergometer training. Med. Sci.circulatory changes after training of the arms and Sports 8:18-22, 1978.legs. Am. J. Physiol. 225:675-682, 1973. 67. Stamford, B.A., R.W. Cuddihee, R.J.

65. Lewis, S., P. Thompson, N.H. Areskog, P. Moffatt, and R. Rowland. Task specific changesVodak, M. Marconyk, R. DeBusk, S. Mellen and in maximal oxygen uptake resulting from armW. Haskell. Transfer effects of endurance training versus leg training. Ergonomics 21:1-9, 1978.to exercise with untrained limbs. Eur. J. Appl. 68. Loftin, M., R.A. Boileau, B.H. Massey, andPhysiol. 44:25-34, 1980. T.G. Lohman. Effect of arm training on central

66. Ridge, B.R., F.S. Pyke, and A.D. Roberts. and peripheral circulatory function. Med. Sci.rFasponses to kayak ergometer performance after Sports Exerc. 20:136-141, 1988.

911461 13

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.11461 19

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