Ergonomics International

It was the purpose of this study to examine whether replacing long pants (P) with shorts (S) would reduce the heat stress of wearing firefighting protective clothing during exercise in a warm environment. Twenty-four Toronto Firefighters were allocated to one of four groups that performed heavy (H, 4.8?km·h^?1, 5% grade), moderate (M, 4.5?km·h^?1, 2.5% grade), light (L, 4.5?km·h^?1) or very light (VL, 2.5?km·h^?1) exercise while wearing their full protective ensemble and self-contained breathing apparatus. Participants performed a familiarization trial followed by two experimental trials at 35°C and 50% relative humidity wearing either P or S under their protective overpants. Replacing P with S had no impact on the rectal temperature (T_re) or heart rate response during heavy or moderate exercise where exposure times were less than 1?h (40.8?±?5.8 and 53.5?±?9.2?min for H and M, respectively while wearing P, and 43.5?±?5.3 and 54.2?±?8.4?min, respectively while wearing S). In contrast, as exposure times were extended during lighter exercise T_re was reduced by as much as 0.4°C after 80?min of exercise while wearing S. Exposure times were significantly increased from 65.8?±?9.6 and 83.5?±?11.6?min during?L and VL, respectively while wearing P to 73.3?±?8.4 and 97.0?±?12.5?min, respectively while wearing S. It was concluded that replacing P with S under the firefighting protective clothing reduced the heat stress associated with wearing the protective ensemble and extended exposure times approximately 10?–?15% during light exercise. However, during heavier exercise where exposure times were less than 1?h replacing P with S was of little benefit.     

Estimated aerobic performance and energy cost of severe exercise of 24 h duration

Abstract

The maximal aerobic performance ([Vdot]O₂max) and energy cost of running at various speeds of two ultra-distance athletes were measured in the laboratory on a motor driven treadmill and the results related to observations made during a 24 h race. The athletes finished 1st and 2nd in the event and covered distances of 251·46 km and 234·56 km respectively during the 24 h period. From the measurements in the laboratory it was calculated that the average speeds sustained by the athletes during the competition were equivalent to an O₂ cost of 36·4 ml kg^?1 min^?1 and 35·3 ml kg^?1 min^?1 which represented approximately 50% of their [Vdot]O₂max. During the race the winner expended an estimated 77,829 kJ (18.595 kcal) which is three times the highest recorded value in the most severe industrial work. By the nature of the activity this figure must be regarded as at or near the upper limit of sustainable energy expenditure by man during a complete uninterrupted 24 h circadian cycle.     

Energy expenditure and clearing snow: a comparison of shovel and snow pusher

In order to assess the energy demands of manual clearing of snow, nine men did snow clearing work for 15 min with a shovel and a snow pusher. The depth of the snowcover was 400–600 mm representing a very heavy snowfall. Heart rate (HR), oxygen consumption ([Vdot]O₂), pulmonary ventilation ( [Vdot]O_E), respiratory exchange ratio (R), and rating of perceived exertion (RPE) were determined during the work tasks. HR, [Vdot]O_E, R, and RPE were not significantly different between the shovel and snow pusher. HR averaged (± SD) 141 ± 20bmin_-1 with the shovel, and 142 ± 19 beats-min_-1 with the snow pusher. [Vdot]O₂was 2·1 ± 0·41 min_-1 (63 ± 12% [Vdot]O₂max) in shovelling and 2·6 ± 0·51 min_-1 (75 ± 14% [Vdot]O₂max) in snow pushing (p< 0·001). In conclusion manual clearing of snow in conditions representing heavy snowfalls was found to be strenuous physical work, not suitable for persons with cardiac risk factors, but which may serve as a mode of physical training in healthy adults.     

The energy cost of women walking and running in shoes and boots∗

The purpose of this study was to determine the difference in energy cost for women walking and running in shoes versus heavier boots. Seven subjects wore athletic shoes (mean weight = 514 ± 50g) and leather military boots (mean weight = 1371 ± 104g) at three walking speeds (4·0, 5·6 and 7·3km/hour) and two running speeds (8middot;9 and 10·5 km/hour). During each walking and running trial oxygen uptake ([Vdot]O₂ ml kg^?1 min^?1) was measured. The [Vdot]O₂ for women wearing boots were significantly higher (P < 0·05) than for shoes for both walking and running, with the exception of the slowest walking speed. The average increment in energy cost was 1·0% per 100-g increase in weight per pair of footwear. These results are similar to those reported for men from other studies which found increments in energy cost of 0·7 to 0·9% per 100-g increase in weight of footwear.     

The influence of flywheel weight and pedalling frequency on the biomechanics and physiological responses to bicycle exercise†

The physiological, subjective and biomechanical effects of altering flywheel weight and pedalling rate on a Quinton Model 870 bicycle ergometer were studied. Steel plates were added to the flywheel to increase its weight to 35·9 kg with a moment of inertia of 1·65 kg m². A 1·5 kg spoked wheel with a moment of inertia of 0·1 kg m² was used as the light flywheel. Eight subjects pedalled on two separate occasions for 6 min at 40, 50, 60, 70, 80 and 90 r.p.m. with workload levels representing 30 and 60% of their [Vdot]O₂max with each flywheel. Force plate pedals were used to measure the total resultant force on the pedals (F_R ) and the component perpendicular to the crank arm (F_T). A force effectiveness index (FEI) was denned as the average of F_T/F_R over a crank cycle. The result showed no statistically significant change (p<0·05) in [Vdot]O₂, heart rate and rating of perceived exertion of the FEI as a function of flywheel weight except for the [Vdot]O₂ at 50 r.p.m. for the light workload. As the r.p.m. increased from 40 to 90 r.p.m., the FEI decreased from 0·5 to 0·35 with the heavy load and from 0·36 to 0·22 with the light load. Measured physiological, subjective and biomechanical indices did not change significantly with flywheel weight. Increasing the pedalling rate caused a significantly less effective application of forces to the crank arm with only a small change in [Vdot]O₂.     

Aerobic Capacity of Steel Workers in India

Abstract

Seventy-six workers, aged 21–43 y. drawn from three major steel plants—two located in the eastern and one in the central region of India (referred to as Group A, Group B and Group C respectively)—were studied on the bicycle ergometer to determine their aerobic capacity ([Vdot]_O2max), Both the direct and indirect methods were employed, the direct one being used only in the case of the workers in Group C. The mean [Vdot]_O2max of these workers was found to be 42·6 cm³ kg^?1 with a standard error of ± 0·71 cm³ kg^?1 min^?1. The highest values were observed among the workers in Group B (mean 47·0± 1·35 (S.E.)cm³kg^?1 min^?1) who are ethnically distinct and have a high level of customary activity, and the lowest among workers in Group C (mean: 39·0±0·74(S.E.) cm³kg^?1 min^?1).

As expected, the [Vdot]_O2max was found to be correlated positively with body weight, and negatively with age in a multiple regression analysis. Furthermore, the active Group B has values for [Vdot]_O2max that are significantly higher than those for the other Groups, a difference that is not attributable to weight or age.     

Metabolic,cardiovascular and spinal strain of a representative fuel replenishment task

The metabolic, cardiovascular and spinal strain of a representative fuel replenishment task for a tank crew were assessed using nine military subjects wearing coveralls in a comfortable ambient climate. The task involved lifting 5 gal jerry cans (weighing 23·4?kg) from the ground to a height representing a tank deck (1·676 m) at a rate of two lifts per minute for 15 min. Oxygen uptake ([Vdot]O₂), minute ventilation ([Vdot]E), heart rate (HR) and intra-abdominal pressure (IAP) were monitored continuously. After 15 min of lifting the mean [Vdot]O₂ was 0·821 min^?1 (S.D. 0·18). This was 27% of the predicted [Vdot]O₂ max. The mean [Vdot]E was 21·81 min^?1 (S.D.4·1) and the HR was 111·3 beats min^?1 (S.D. 17·8). The mean peak IAP was 105·6?mmHg, with 56% of the peak IAPs exceeding 90?Hg. The mean intrasubject coefficient of variation was 10·7% (range 7·2–24·2). In a separate series of 20 consecutive bimanual straight arm vertical lifts of 10?kg at 15 s intervals, the mean intrasubject COV% was 7·2% (range 3·2–11·2%). The replenishment task was considered acceptable in terms of the metabolic and cardiovascular strain. In terms of spinal strain, there may be an unacceptable risk of back injury if the task was normally undertaken as part of a soldier's full-time occupation over many years     

Aerobic capacity of urban women homemakers in Bombay

Twenty-six healthy women homemakers residing in the metropolitan city of Bombay were studied on a treadmill and a cycle ergometer to determine their aerobic capacity ([Vdot]O₂ max) with a view to evaluating their cardio-respiratory fitness and ascertaining the job-demand-fitness-compatibility in household activities. The [Vdot]O₂ max was found to be significantly higher in treadmill experiments, i.e. 15% in absolute value and 18% in relative value, as compared with that obtained by cycle ergometry (p < 0·001). A much higher difference was observed in values derived from the two methods on the same subjects (i.e. 28% in absolute value and 31% in relative value). Thus, the [Vdot]O₂max obtained from treadmill experiments may be regarded as the maximal aerobic power or the highest oxygen uptake that an individual can attain during exercise, which in the sample of the present study was recorded as 1·901 min ^?1 (33·9 ml kg ^?1 min ^?1). The findings also revealed that age and body weight have a direct influence on [Vdot]O₂max, which was found to be significantly correlated, positively with the latter and negatively with the former (p<0·01 in both cases). The physiological job-demand of household activities seems to be compatible in relation to the [Vdot]O₂max of the homemakers.     

The energy cost and heart-rate response of trained and untrained subjects walking and running in shoes and boots

Abstract

To determine the difference in the energy cost of walking and running in a lightweight athletic shoe and a heavier boot, fourteen male subjects (six trained and eight untrained) has their oxygen uptake ([Vdot]O₂) measured while walking and running on a treadmill. They wore each type of footwear, athletic shoes of the subjects' choice (average weight per pair = 616 g) and leather military boots (average weight per pair = 1776g), at three walking speeds (4·0, 5·6 and 7·3 km hour^?1) and three running speeds (8·9, 10·5 and 12·1 km hour^?1). The trials for running were repeated at the same three speeds with the subjects wearing shoes and these shoes plus lead weights. The weight of the shoes plus the lead weights was equal to the weight of the subjects' boots. The [Vdot]O₂values with boots were significantly (p < 0·05) higher (5·9?10·2%) at all speeds, except the slowest walk, 4·0 km hour^?1Also, [Vdot]O₂with shoes plus lead weights were significantly (p<0·05) higher than shoes alone. Weight alone appeared to account for 48-70% of the added energy cost of wearing boots. The relative energy cost ([Vdot]O₂, ml kg^?1?) of trained and untrained subjects were the same at all speeds. These data indicate that energy expenditure is increased by wearing boots. A large portion of this increase may be attributed to weight of footwear. In addition, the increased energy cost of locomotion with boots appears to place a limiting stress on untrained subjects.     

Metabolic and perceptual responses while carrying external loads on the head and by yoke

Abstract

The purpose of this study was to determine the metabolic efficiency and perceptual acceptability of transporting external loads on the head and by yoke. Ten young males (24·2 ±3·9 years) of average physical fitness ([Vdot]O_2max=49·8 ± 6·5ml kg^-1 min^-1) walked for 6min on a level motor-driven treadmill at 53·6, 73·8 and 93·9m min^-1. Subsequently, all subjects carried external loads (11·6, 16·1 and 20·6 kg) at the same speeds using the headpack (HP), transverse yoke (TY) and frontal yoke (FY) modes of load carriage. Measurements were obtained for oxygen uptake ([Vdot]O₂ l min^-1), local ratings of perceived exertion (RPE-L) and the overall perceived exertion (RPE-O). The [Vdot]O₂ was used in the computation of the metabolic efficiency ([Vdot]O₂ ml kg total weight^-1 min^-1).

Significant main effects (mode, load and speed) and three interaction effects (mode × load, mode × speed and load × speed) were obtained for metabolic efficiency. Scheffé post hoc analysis revealed that the metabolic efficiency for the TY and HP were greater than the FY while transporting the 16·1 and 20·6kg loads at all walking speeds (p <0·05). No significant loss in metabolic efficiency was found while carrying the 20·6kg load at 53·6 m min^-1. At 93·9 m min^-1, all external loads transported were associated with a loss in metabolic efficiency. The RPE-L for the HP was lower than the FY (p < 0·05). Both the RPE-0 and RPE-L increased as the walking speeds and external loads were increased. The findings suggest that load transportation using the FY system is both physiologically and perceptually unacceptable.     

The reliability of the Extra Load Index as a measure of relative load carriage economy

Abstract

The aim of this study was to measure the reliability of the extra load index (ELI) as a method for assessing relative load carriage economy. Seventeen volunteers (12 males, 5 females) performed walking trials at 3 km·h^?1, 6 km·h^?1 and a self-selected speed. Trial conditions were repeated 7 days later to assess test–retest reliability. Trials involved four 4-minute periods of walking, each separated by 5 min of rest. The initial stage was performed unloaded followed in a randomised order by a second unloaded period and walking with backpacks of 7 and 20 kg. Results show ELI values did not differ significantly between trials for any of the speeds (p = 0.46) with either of the additional loads (p = 0.297). The systematic bias, limits of agreement and coefficients of variation were small in all trial conditions. We conclude the ELI appears to be a reliable measure of relative load carriage economy.

Practitioner Summary: This paper demonstrates that the ELI is a reliable measure of load carriage economy at a range of walking speeds with both a light and heavy load. The ELI, therefore, represents a useful tool for comparing the relative economy associated with different load carriage systems.     

Decreased submaximal oxygen uptake during short duration oral contraceptive use: a randomized cross-over trial in premenopausal women

Long-term oral contraceptive (OC) use is known to be associated with changes in haemostasis, cardiovascular dynamics, and carbohydrate and lipid metabolism. Less well documented are the short-term variations in cardiorespiratory responses to exercise during the menstrual cycle of OC users. In this study the short-term effects of the usage of OC on cardiorespiratory and ventilatory responses to submaximal exercise were examined. Ten women (age= 23 ± 3 years) on monophasic OC were tested at three different times during their ‘cycle’ : during menstruation, off OC use (off OC: days 2 –; 4), early on OC use (EOC: days 7 – 9) and late on OC use (LOC: days 19 – 21). Times of testing were assigned randomly. On each occasion participants performed a continuous 12-min run exercise on a treadmill at three submaximal intensities (averaging 7, 8 and 9 km h^?1), each for 4 min. Heart rate, ventilation ([Vdot]E), oxygen uptake ([Vdot]O₂), carbon dioxide output ([Vdot]CO₂), respiratory exchange ratio and running economy were assessed in the last minute of each stage of exercise. No significant variations were observed between the different times for heart rate, [Vdot]E, and [Vdot]CO₂ irrespective of the stage of exercise (p > 0.05). Using two-way analysis of variance (ANOVA) with repeated measures on both factors (three stages and three times), [Vdot]O₂ (ml kg^?1 min^?1) was lower by 3% to 5.8% when participants were on early and late OC use compared to off OC regardless of the stage of the exercise (F(2,18)= 6.3; p= 0.008). Running economy (ml O₂ kg^?1 km^?1) was significantly improved (lower values) when women were on late OC use compared to off OC regardless of the stage of exercise. No significant interaction effect between stage of exercise and time of pill usage was demonstrated in any of the parameters studied. Results suggest that oral contraceptive users may expect lower [Vdot]O₂ and better running economy during the pill ingestion phase and consequently have implications for exercise performances.     

Impact of fluid replacement on heat storage while wearing protective clothing

This study used partitional calorimetry to determine the influence of fluid replacement on heat storage during uncompensable heat stress. Eight males performed either light (L; level treadmill walking at 0.97 m·s^-1 (3.5 km·h^-1) or heavy (H; 1.33 m·s^-1 (4.8 km·h^-1) at a 4% grade) exercise at 40°C and 30% relative humidity while wearing nuclear, biological and chemical (NBC) protective clothing. Subjects received either no fluid (NF), or 200 or 250 ml of fluid (F) as warm water at ~ 35°C immediately before and every 15 min during the L and H trials respectively. Similar reductions in heart rate were observed at both metabolic rates with F but rectal temperature responses were not different between F and NF. Tolerance time was extended during L/F (106.5±22.1 min) compared with L/NF (93.1±20.8 min) but fluid replacement had no influence during H (59.8±9.5 min and 58.3±11.1 min for F and NF respectively). Fluid replacement also had no effect on the rate of heat storage during L (108.2±20.6 W·m^-2 and 111.0±22.6 W·m^-2 for F and NF respectively) and H (172.5±11.5 W·m^-2 and 182.1±15.8 W·m^-2 for F and NF respectively). However, heat storage expressed per unit of mass was significantly increased during L/F (18.5±4.0 kJ·kg^-1) compared with the other trials (16.3±4.8 kJ·kg^-1, 16.6±3.0 kJ·kg^-1 and 16.7±4.0 kJ·kg^-1 for L/NF, H/F and H/NF respectively). It was concluded that fluid replacement does not alter the rate of heat storage during uncompensable heat stress but does increase the heat storage capacity during light exercise when tolerance times are > 60 min.     

Permissible loads based on energy expenditure measurements

The literature is reviewed and, based on this, it is suggested that the upper general tolerance limit over an 8-hour work day, consisting of mixed physical work, including handling operations, is approximately 30–35% [Vdot]O₂ max (on bicycle legwork or treadmill). Therefore, the individual tasks must be adjusted to a metabolic level not exceeding 30–35% [Vdot]O₂ max in the majority of the labour force or may be more realistic in specific groups within the labour force (young/ old, male/female). The following metabolic values are suggested (1 [Vdot]O₂ ): males <40 years: 0·7males>40 years: 0·6; females < 40 years: 0·6; females >40 years: 0·5. It is important to notice that even with a metabolic rate below 30–35% [Vdot]O₂ max it is possible that local overstrain and/ or fatigue in the back muscles during, for example, manual handling operations of long duration can occur     

A new kayak ergometer based on wind resistance

Abstract

An ergometer for kayak paddlers has been developed and used for winter training, measurements of work capacity and maximal oxygen uptake ([Vdot]O₂ max). Force is transmitted from the paddle by means of a wire connected to a flywheel mounted with six 9 × 9cm blades. Resistance, therefore, is based on wind turbulence generated by the flywheel. The mechanical efficiency of the ergometer at 63% (range 48-77) of [Vdot]O₂ max was 17% (range 16-18) (n= 13). The [Vdot]O₂ max was similar during bicycling (median 4·9; range 4·4-5·4l/min), arm cranking (median 4·8; range 4·3-5·11/min), on-water rowing in a kayak (median 4·7; range 4·0-4·91/min) and during rowing the kayak ergometer (median 4·8; range 4·3-5·21/min), (n = 6, p> 0·05). Work capacity during a 5 min ‘all-out’ test was 272 W (range 253–304 W) on the kayak ergometer (n = 17). The use of the ergometer for training helped to increase the aerobic power during arm exercise of Danish paddlers. Before introduction of the ergometer (February 1986), their VO₂ max was 4·6 (range 3·8-5·2) 1/min while 12 months later, it was 50 (range 4·2–5·7) 1/min (n = 14, p < 0·01). The ergometer has thus been found.useful for training and evaluation of work capacity in kayak paddlers.     

Preliminary observations on parameters of human location

Abstract

A preliminary experimental field investigation was conducted on seventeen normal male adults to study the important observable parameters of human locomotion and the interrelationship existing among them. New generalized terms such as specific speed (statures s^?1), specific energy consumption (kJ kg^?1 min^?1), percentage increase of peak heart rate and a non-dimensionalized term, relative step length, have been introduced. Superiority of cadence and specific speed over speed and specific energy consumption over energy consumption has been observed and a single linear relationship connecting specific speed and specific energy consumption up to a speed of 6·7 m s^?1 (24 km h^?1) has been seen. Stair climbing and Baithaki exercises have been included as two other rhythmic activities for the sake of comparison with locomotion. Use of cadence as a relatively more important observable gait parameter for walking or running activity as well as for other rhythmic activities has been suggested. These findings have potential for application in the field of work study and industrial engineering.     

Energy Expenditure of Heavy Load Carriage

Abstract

Fourteen subjects (22 yr, 175 cm, 72 kg) walked for 20 min on a treadmill at 3-2, 4-8, or 64 km h^-1 carrying 35, 40, 45, or 50 kg; during a second phase, ten additional subjects (22 yr, 178 cm, 75 kg) attempted to walk for 45 min at the same speeds carrying 60, 65. or 70 kg Energy expenditure when expressed as cm³ oxygen per minute per kilogramme of total weight (man + clothing + load) agreed, for the no load condition, with literature values. After deducting the individual's no load cost, the resulting net energy expenditure for carrying the loads, when expressed as cm³ kg^-1 min^-1 was generally constant at each speed; i.e. loads from 35 to 70 kg showed no statistical differences in energy expenditure per kilogramme at 3 2 and 4 8 km h^-1. At 6-4 km h^-1 carrying 70 kg, the average measured cost per kg was statistically different (p < 005) than carrying 35 kg at this speed; subjects were working at greater than 90% of their maximal [Vdot]₀₂ levels carrying 70 kg. However. similar comparison of the measured cost per kg between loads of 40 and 65 kg was statistically the same at 6 4 km h^-1. The general constancy of measured energy expenditure per kg for loads even up to 70 kg, probably depends on the condition that the load is well balanced and close to the centre of the body. As reported earlier, higher costs are associated with loads in unbalanced positions. Thus, the limitations commonly encountered in load carrying capacity may arise from poor positioning of the load rather than from the weight of the load per     

Hyperoxia improves maximal exercise with the self-contained breathing apparatus (SCBA)

The effects of hyperoxia on maximal exercise while breathing from a self-contained breathing apparatus (SCBA) were studied in 25 males. Each participant completed three graded exercise tests (GXT) for the assessment of maximal oxygen uptake (Vdot;O _2max): two with 20.95 ± 0.28% O₂ and the third (GXT₄₀) while breathing hyperoxia (40.64 ± 1.29% O₂). No significant differences were found between the two normoxic tests, except for a 16W increase in maximal power output (PO_max) in the second trial (GXT₂₁). Compared to GXT₂₁, hyperoxia significantly increased Vdot;O _2max and PO_max by 10.0 ± 3.8% and 10.2 ± 7.1%, respectively. This was likely due to an increase in O₂ delivery as suggested by the significantly higher oxyhemoglobin saturation. The increase in Vdot;O _2max with hyperoxia was similar to the increase in carbon dioxide production (9.3 ± 6.5%). No other significant differences were found at maximal exercise. However, at the intensity that elicited Vdot;O _2max in GXT₂₁, pulmonary ventilation and SCBA mask pressure were significantly lower during GXT₄₀, suggesting a decrease in the work of breathing. These findings could have significant implications for occupations that involve heavy work with SCBA.     

The Operation of the National Grid System

Abstract

To investigate whether the exercise intensity affects sweating efficiency (η_sw) during exercise under mild environmental conditions, six healthy males, aged 22 ± 2 years, performed three bicycle ergometer exercises at varying intensities (73W: Ex-1, 103W: Ex-2 and 133W: Ex-3) for 40min under the conditions of 25°C room temperature, 50% relative humidity and 0·3-0·4 m s ^?1 wind velocity. Heart rate, oxygen consumption, rectal temperature (T _re), mean skin temperature (T¯ _sk 4 skin sites) and total sweat rate were determined intermittently throughout the experiments. Moreover, heat loss by evaporation (E), radiation (R), convection (C) and η_sw were calculated using the heat balance equations. The findings concerning thermoregulatory parameters under the three experimental conditions were summarized as follows: (1) the higher the exercise intensity, the larger the values of T_re and T¯ _sw at the end of exercise and E, R and C during exercise (2) the mean values ± SE of η_sw were 55·4 ± 5·1, 63·2 ± 5·2 and 58·5 ± 1·9% for Ex-1, Ex-2 and Ex-3, respectively. The results suggest that exercise intensity would have no effect on η_sw in this mild thermal environment.     

Physiological factors affecting upper body aerobic exercise

This study examined the influence selected physiological measurements have upon peak oxygen uptake (peak [Vdot]O₂) elicited by upper body (arm crank) exercise employing crank rates of 30 and 70 r.p.m. Nine male volunteers completed: two maximal effort arm crank tests, one cycle exercise maximal aerobic power (AP) test, measurements of isokinetic elbow extension strength (ES), isometric grip strength (GS) and arm volume (AV). Partial correlation coefficients (R) were obtained from a multiple regression analysis. For the 30 r.p.m. protocol, peak [Vdot]O₂ was strongly related to AP (r=0·80; R = 0·51) and moderately related to ES (r=?0·41; R =?0·41) and GS (r=0·40; R = 0·30). For the 70 r.p.m. protocol, peak [Vdot]O₂ was found to be strongly related to AP (r=0·94; R=0·88). AV values were not found to have a marked influence on upper body peak [Vdot]O₂ at either crank rate. These data indicate that aerobic power for cycle exercise is the most important determinant of upper body aerobic exercise performance.