Influence of lifting technique on perceptual and cardiovascular responses to submaximal repetitive lifting

Oxygen consumption ( O₂), heart rate, ventilation and central rating of perceived exertion (RPE) in repetitive lifting while executing squat and stoop techniques were investigated in ten male forestry workers. In all five mass/frequency combinations studied, O₂ was significantly higher for the squat than for the stoop technique. No differences were found in RPE between the techniques. The O₂ and RPE recordings were also related to those obtained during maximal repetitive lifting (same lifting technique) and maximal treadmill running. The O₂ expressed as a percentage of that obtained during maximal repetitive lifting with the same lifting technique was defined as relative aerobic intensity (% O_{2max, lifting}). The % O_{2max, lifting} was not significantly different between the techniques except for the lowest mass lifted (1 kg). This study therefore would support the hypothesis that RPE is more closely related to % O_{2max, lifting} than to absolute aerobic intensity. Related to maximal treadmill running, it was demonstrated for both lifting techniques that relative RPE (percentage of the RPE during maximal running) was more accurate than relative O₂ (percentage of maximal O₂ during maximal running) for determining the % O_{2max, lifting} in repetitive lifting. The study showed that the higher O₂ during squat. lifting compared to stoop lifting was caused by the O₂ expended in lifting and lowering the body rather than the O₂ expended lifting and lowering the external mass. It was concluded that the stoop technique was not superior to the squat technique in terms of central RPE. Based on % O_{2max, lifting}, there may be a rationale for choosing the stoop technique during repetitive lifting with light masses, but not with heavy masses.     

Ventilatory response during incremental exercise tests in weight lifters and endurance cyclists

Summary The effect of a progressively increasing work rate (15 W·min^–1) up to exhaustion on the time course of O₂ uptake ( ), ventilation ( ) and heart rate (HR) has been studied in weight lifters (WL) in comparison to endurance cyclists (Cycl) and sedentary controls (Sed). and were measured as average value of 30-s intervals by a semiautomatic open circuit method. was 2.55±0.33; 4.29±0.53 and 2.86±0.19·min^–1 in WL, Cycl and Sed respectively. With time and work rate, while and HR increased linearly, changed its slope at two levels. The 1st change occured at a work load corresponding to a mean (± SD) of 1.50±0.26; 1.93±0.34; and 1.23±0.14 l·min^–1 in WL, Cycl, and Sed respectively. values corresponding to the second change of slope were 2.18±0.32 in WL; 3.48±0.53 in Cycl and 2.17±0.28 l·min^–1 in Sed. The first change of slope might be the consequence of the different readjustment of on-response and hence of early lactate in the different subjects. The second change seems to be comparable to the conventional anaerobic threshold and is achieved in all subjects when vs time slope is 7–10 l·min^–1/min of exercise.This work has been supported in part by a grant from the Italian National Research Council (CNR)     

The influence of inspired oxygen on the oxygen uptake response to ramp exercise

The relation between and work rate (WR) was examined in seven male subjects who performed ramp (1 W·3 s^–1) two-legged cycle ergometry to exhaustion while inspiring either hypoxic (12% O₂), normoxic (21% O₂), or hyperoxic (40% O₂) air. The anaerobic threshold was estimated from respiratory gas exchange data and is thus referred to as the respiratory gas exchange threshold (RGET). Prior to the RGET, the was greater under normoxic [mean (SD); 10. 19(1.04) ml O₂·min^–1·W^–1] and hyperoxic [10.44 (0.72)] conditions compared with hypoxia [9.34 (0.89)]. Above the RGET, the for hypoxia [8.91 (0.63)], normoxia [10.40 (0.77)], and hyperoxia [11.08 (0.48)] were all significantly different from each other. These data indicated that for two-legged, cycle, ramp ergometry in normoxia below the RGET, both the and response time was constant. Above the RGET, the normoxic response was the net result of a declining and a longer response time to the unsteady state character of a ramp exercise protocol.     

Diffusion-limited gas mixing in the lung and its consequences for transpulmonary gas transport

The ratio of alveolar ventilations of He and SF₆ ( ) was determined in 7 healthy male subjects at rest and at three different levels of exercise on a bicycle ergometer (75, 150 and 225 W). This ratio was calculated from the ratio of the specific ventilations for these gases which were obtained from the decay of the end-tidal partial pressures of He and SF₆ during a simultaneous, multiple-breath washout. In all experiments, for He was larger than for SF₆. On the average, was equal to 1.09, and the mean values of this ratio at rest and at the three levels of exercise were not significantly different. Therefore, the difference in for He and SF₆ increased with increasing work load. Further, we used the mean value obtained for , to calculate the ratio of excretion values (E₁/E₂) for pairs of hypothetical tracer gases with equal blood-gas partition coefficients and with different diffusivities in the gas phase. E₁/E₂ ranged from anity for =0 to about 1.08 for =10. At a given , E₁/E₂ decreased with increasing ventilation-perfusion ratio of the lung. Thus, the difference between the excretion values of light and heavy tracer gases will be most pronounced under rest conditions and for gases that are well soluble in blood.     

Aerobic and anaerobic contribution to Wingate test performance in sprint and middle-distance runners

We investigated the aerobic and anaerobic contributions to performance during the Wingate test in sprint and middle-distance runners and whether they were related to the peak aerobic and anaerobic performances determined by two commonly used tests: the force-velocity test and an incremental aerobic exercise test. A group of 14 male competitive runners participated: 7 sprinters, aged 20.7 (SEM 1.3) years, competing in 50, 100 and 200-m events and 7 middle-distance runners, aged 20.0 (SEM 1.0) years, competing in 800, 1,000 and 1,500 m-events. The oxygen uptake ( ) was recorded breath-by-breath during the test (30 s) and during the first 20 s of recovery. Blood samples for venous plasma lactate concentrations were drawn at rest before the start of the test and during the 20-min recovery period. During the Wingate test mean power ( ) was determined and three values of mechanical efficiency, one individual and two arbitrary, 16% and 25%, were used to calculate the contributions of work by aerobic ( _{aer,ind,16%,25%}) and anaerobic ( _{an,ind,16%,25%}) processes. Peak anaerobic power ( _an,peak) was estimated by the force-velocity test and maximal aerobic energy expenditure ( _aer,peak) was determined during an incremental aerobic exercise test. During the Wingate test, the middle-distance runners had a significantly greater than the sprinters (P < 0.001), who had significantly greater venous plasma lactate concentrations (P < 0.001). Moreover, _{aer,ind,16%,25%} were also significantly higher (P < 0.05) in the middle-distance runners [ _aer,ind 45 (SEM 4) % vs 28 (SEM 2) %; _aer,16% 30 (SEM 3) % vs 19 (SEM 2) %; _aer,25% 46 (SEM 3) % vs 29 (SEM 2)%]; _{an,ind,16%,25%} in the sprint runners (P < 0.05) [ _an,ind 72 (SEM 3) % vs 55 (SEM 4) %; _an,16% 81 (SEM 2) % vs 70 (SEM 3) %; _an,25% 71 (SEM 2) % vs 54 (SEM 3) %]. The _aer,ind/ _aer,peak and × _an,ind/ _an,peak ratios, however, were not significantly different between the two groups of athletes. These results would indicate that the sprinters and middle-distance runners used preferentially a metabolic system according to their speciality. Nevertheless, under the conditions of its experiment, they seemed to rely on the same percentage of both peak anaerobic and peak aerobic performance for a given exercise task.     

Effects of temperature on the maximal instantaneous muscle power of humans

Summary The maximal instantaneous muscle power ( ) probably reflects the maximal rate of adenosine 5-triphosphate (ATP) hydrolysis ( ), a temperature-dependent variable, which gives rise to the hypothesis that temperature, by affecting , may also influence . This hypothesis was tested on six subjects, whose vastus lateralis muscle temperature (T _muscle) was monitored by a thermocouple inserted approximately 3 cm below the skin surface. The was determined during a series of high jumps off both feet on a force platform before and after immersion up to the abdomen for 90 min in a temperature controlled (T=20±0.1°C) water bath. ControlT _muscle was 35.8±0.7°C, with control being 51.6 (SD 8.7) W · kg^–1. After cold exposure,T _muscle decreased by about 8°C, whereas 27% lower. The temperature dependence of was found to be less (Q ₁₀ < 1.5, whereQ ₁₀ is the temperature coefficient as calculated in other studies) than reported in the literature for . Such a lowQ ₁₀ may reflect an increase in the mechanical equivalent of ATP splitting, as a consequence of the reduced velocity of muscle contraction occurring at lowT _muscle.     

The effects of dietary manipulation upon the respiratory exchange ratio as a predictor of maximum oxygen uptake during fixed term maximal incremental exercise in man

Summary This study examined the effects of dietary manipulation upon the respiratory exchange ratio ( ) as a predictor of maximum oxygen uptake ( ). Seven healthy males performed fixed term maximal incremental treadmill exercise after an overnight fast on three separate occasions. The first test took place after the subjects had consumed their normal mixed diet (45±5% carbohydrate (CHO)) for a period of three days. This test protocol was then repeated after three days of a low CHO diet (3±2% CHO), and again after three days of a high CHO diet (61±5% CHO). Respiratory gases were continuously monitored during each test using an online system. No significant changes in mean exercise oxygen uptake ( ), or maximum functional heart rate (FHR_max) were found between tests. Mean exercise carbon dioxide output ( ) and R were significantly lower than normal after the low CHO diet (bothp<0.001) and significantly higher than normal after the high CHO diet (bothp<0.05). Moreover, compared with the normal CHO diet, the R-time relationship during exercise was at all times significantly (p<0.001) shifted to the right after the low CHO diet, and shifted to the left, being significantly so (p<0.05) over the final 5 min of exercise, after the high CHO diet. As a result, predictions of based on the R-time relationship were similar to recorded after the normal CHO dietary condition (-1.5±1.9%), but higher after the low CHO diet (+14.8±3.9%,p<0.001) and lower after the high CHO diet (–7.0±4.5%,p<0.01). These results indicate that dietary manipulation can significantly affect respiratory gas exchanges during fixed term maximal incremental exercise, and by doing so can significantly influence predictions of based on R.     

Physiological responses of women during lifting exercise

Summary Physiological responses were measured in 7 women subjects who lifted boxes weighing 6.8, 15.9 or 22.7 kg from the floor to a height of 60 cm. After training and establishing the O₂ max, the boxes were lifted for 1 h at 30, 50, and 60% O₂ max. The changes in heart rate, O₂, the integrated EMG during lifting and the loss of isometric hand-grip endurance after lifting were used to assess the development of fatigue. There was no evidence of fatigue at 30% O₂ max but fatigue did exist in some conditions at 50% and in all conditions at 60% O₂ max. It is suggested that fatigue is unlikely to occur while lifting boxes up to 15.9 kg weight at 35–40% O₂ max, i.e., at rates of lifting varying from 5 to 7 times per min.     

Criteria for maximum oxygen uptake in progressive bicycle tests

Summary Different criteria for O₂ max in a progressive bicycle exercise were studied in 115 healthy subjects. In the repeated progressive tests performed on 16 men, aged 25–35 years, three types of O₂ response against work load were noticed: a linear increase, an unexpectedly high increase, and a plateau; the last two only appearing when O₂ max was achieved. The last three O₂ values at least were required to define the plateau. Most commonly, subjective exhaustion was achieved, respiratory quotient (R) was over 1.15 and maximal heart rate (HR) at the estimated level for age, though O₂ max was not achieved. No significant differences were found between peak O₂ in the first progressive test (mean=2.95 l/min), the second progressive test (mean=3.14 l/min), or the constant-load test (mean=3.05 l/min). In the progressive test performed once on 55 men and 44 women, aged 35–62 years, subjective exhaustion was achieved by most of the subjects, but the plateau in O₂ was shown only in 17 subjects, and the peak O₂ values were somewhat lower than expected. Moreover, R max did not correlate with peak O₂, and was over 1.15 only in 9 subjects, and HR max was often below the estimated level. Thus, the progressive test appeared to be convenient in testing the physical work capacity of the subjects, but the establishment of the physiological maximum was more difficult: the relatively uncommon plateau in O₂ was the only useful criterion for O₂ max, the value of other criteria being unacceptable.     

Responses of people with coronary artery disease to common lawn-care tasks

The primary purpose of the present study was to determine oxygen uptake ( ) and heart rate (HR) responses of patients with coronary artery disease (CAD) to common lawn-care activities. The study was conducted in three phases. In phase I, 8 men with CAD performed 30 min of push motorized lawn mowing at a self-paced rate. In phase II, 9 men with CAD performed push (no power) mowing, trimming (power and manual), and raking for 8 min each. In phase III, age-matched men and women with and without CAD (9–11 per group) performed self-propelled motorized mowing and push motorized mowing. In phase I, averaged 17.3 (SEM 3.8) ml · kg^–1 · min^–1 during 30 min of mowing. Relative effort was 68 (SEM 1) and 76 (SEM 4)% of treadmill maximal ( ) and HR, respectively. In phase II, mean ranged from 8.6 (SEM 0.4) with grass trimming to 22.2 (SEM 1.6) ml · kg^–1 · min^–1 with push manual mowing. With self-propelled mowing at three speeds in phase III, mean of the CAD groups ranged from 9.5 (SEM 0.3) to 13.8 (SEM 1.4) ml · kg^–1 · min^–1 and represented 37%–62% . The results indicated that lawn mowing is often performed at an exercise intensity recommended for aerobic exercise training; patients who achieve a treadmill peak capacity of 4 times resting metabolic rate (4 METs) should be able to perform self-propelled motorized lawn mowing (slow speed) and grass trimming at less than 80% peak ; and demands of lawn mowing can be adjusted by equipment selection and/or pace.     

The validity of anaerobic threshold determination by a Douglas bag method compared with arterial blood lactate concentration

Summary Using an open circuit system (Douglas bag method), measurement of the anaerobic threshold (AT) was performed on ten healthy male college students during an incremental exercise test on a bicycle ergometer in an attempt to determine the validity of this method as compared with arterial blood lactate AT measurement.Blood samples were taken from either the radial or brachial artery through a Teflon catheter (3 ml/each time) every minute until the subject's maximal exercise tolerance was reached. Blood lactate was analyzed by the enzymatic method.Differences in work rate, O₂, % O_{2 max}, _E, HR, and R at AT _LA (AT determined by the increase in blood lactate) and at AT _GE (gas exchange AT based on the non-linear increases in _E, CO₂, and other respiratory parameters), respectively, were all found to be statistically insignificant. There was a significant correlation (r=0.866, p<0.01) between AT _LA and AT _GE when expressed in O₂ values (l/min). There was also a significant correlation between AT _LA and O_{2 max} (r=0.778, p<0.01). These results indicate that the commonly used Douglas bag method could provide a valid non-invasive measure of anaerobic threshold.     

Cardiac output in paraplegic subjects at high exercise intensities

Summary The purpose of this investigation was to compare cardiac output ( _c ) in paraplegic subjects (P) with wheelchair-confined control subjects (C) at high intensities of arm exercise. At low and moderate exercise intensity _c was the same at a given oxygen uptake ( O₂) in P and C. A group of 11 athletic male P with complete spinal-cord lesions between T6 and T12 and a group of 5 well-matched athletic male C performed maximal arm-cranking exercise and submaximal exercise at 50%, 70% and 80% of each individual's maximal power output (W_max) . Maximal O₂ ( O_2max) was significantly lower, O_2max per kilogram body mass was equal and maximal heart rate (f _c) was significantly higher in P compared to C. At O₂ of 1.3, 1.5 and 1.7 1-min^–1, and for P 65%–90% of the O_2max, _c was not significantly different between the groups, although, _c in P was achieved with a significantly lower stroke volume (SV) and a significantly higherf _c. Although the SV was lower in P, it followed the same pattern as SV in C during incremental exercise, i.e. an increase in SV until about 45%W _max and thereafter a stable SV. The similar _c at a given O₂ in both groups indicated that, even at high exercise intensities, circulation in P can be considered isokinetic with a complete compensation byf _c for a lower SV.     

A method for determining the maximal steady state of blood lactate concentration from two levels of submaximal exercise

The aim of this study was to estimate the characteristic exercise intensity _CL which produces the maximal steady state of blood lactate concentration (MLSS) from submaximal intensities of 20 min carried out on the same day and separated by 40 min. Ten fit male adults [maximal oxygen uptake _max 62 (SD 7) ml · min^–1 · kg^–1] exercisOed for two 30-min periods on a cycle ergometer at 67% (test 1.1) and 82% of _max (test 1.2) separated by 40 min. They exercised 4 days later for 30 min at 82% of _max without prior exercise (test 2). Blood lactate was collected for determination of lactic acid concentration every 5 min and heart rate and O₂ uptake were measured every 30 s. There were no significant differences at the 5th, 10th, 15th, 20th, 25th, or 30th min between , lactacidaemia, and heart rate during tests 1.2 and 2. Moreover, we compared the exercise intensities _CL which produced the MLSS obtained during tests 1.1 and 1.2 or during tests 1.1 and 2 calculated from differential values of lactic acid blood concentration ([1a^–]_b) between the 30th and the 5th min or between the 20th and the 5th min. There was no significant difference between the different values of _CL [68 (SD 9), 71 (SD 7), 73 (SD 6),71 (SD 11) % of _max (ANOVA test,P<0.05). Four subjects ran for 60 min at their _CL determined from periods performed on the same day (test 1.1 and 1.2) and the difference between the [la^–]_b at 5 min and at 20 min ( ([la^–]_b)) was computed. The [la^–]_b remained constant during exercise and ranged from 2.2 to 6.7 mmol · l^–1 [mean value equal to 3.9 (SD 1) mmol · l^–1]. These data suggest that the _CL protocol did not overestimate the exercise intensity corresponding to the maximal fractional utilization of _max at MLSS. For half of the subjects the _CL was very close to the higher stage (82% of _max where an accumulation of lactate in the blood with time was observed. It can be hypothesized that _CL was very close to the real MLSS considering the level of accuracy of [la^–]_b measurement. This study showed that exercise at only two intensities, performed at 65% and 80% of _max and separated by 40 min of complete rest, can be used to determine the intensity yielding a steady state of [la^–1]_b near the real MLSS workload value.     

Changes in ventilation at the start and end of moderate and heavy exercise of short and long duration

Summary These experiments examined the effect of exercise intensity and duration on the magnitude of the abrupt change in ventilation at the start ( ) and end ( ) of exercise. Five subjects performed constant load treadmill exercise at 50% and 80% of their maximum oxygen consumption ( ) for 6 and 10 min while inspiring atmospheric air. The subjects also completed additional exercise tests at 80% for 10 min while inspiring an oxygen-enriched gas mixture. During each exercise trial ventilation was measured breath-by-breath. The and were determined by using non-linear curve-fitting techniques. The results showed that was greater at the start of the 80-% exercise tests compared to the 50-% tests and that at each level of exercise was greater than . The results also demonstrated that was inversely related to the intensity and duration of exercise. Furthermore, the was not altered subsequent to the inspiration of oxygen-enriched air. These findings have led us to postulate that the stimulus responsible for is reduced during exercise and that the degree of reduction is related to the intensity and duration of exercise. In addition, it was concluded that these changes might occur independently of peripheral chemoreceptor activity.     

The effects of continuous and interval training in women and men

Summary Fourteen Subjects (6 male, 8 female) participated in a training program upon a bicycle ergometer for 7 weeks. Group CT followed a continuous training regimen 4 days per week at 70% O₂ max. Group IT trained by an interval method at 100% O₂ max. The duration of each training session was assigned so that each subject would complete 10,000 kpm of work per session during the first week. Each subsequent week, the work load was increased 3000 kpm. Pretraining tests included O₂ max, standard 7 min tests at 80% O₂ and 90% O₂, an endurance test at 90%, and an intense anaerobic work bout at 2400 kpm. Variables assessed were O₂, HR, and blood lactic acid concentrations. The mean increase in O₂ max was 5.1 ml/kg min (15%) for both groups with a corresponding increase in maximal lactate of 20 mg-%. The response to the post-training tests was nearly identical for both groups: submaximal heart rate at the same absolute work load declined 17 beats/min (CT) and 15 beats/min (IT), submaximal lactate levels declined significantly, endurance ride duration increased 26 min. Continuous and interval training at 70% and 100% O₂ max respectively produce identical changes in heart rate response, blood lactic acid concentration and O₂ max when the total work load is equated per training session.     

Aerobic fitness and body fat of young British males entering the army

Summary Aerobic fitness and percent body fat were measured in a sample of 438 male Army recruits between the ages of 17 and 30 prior to the commencement of training. The sample came from all areas of England and Wales. Aerobic fitness, as represented by maximal oxygen uptake ( O₂ max), was predicted from the Astrand submaximal bicycle heart rate test. Body fat was predicted from four skinfold measurements. Total group means ±SD were: age, 19.5±2.5 years; O₂ max 41.7 ±8.3 ml/kg·min; and body fat, 14.5±4.8% of body weight. O₂ max varied with age, athletic participation and aptitude score. No relationship was found with occupation of parent, prior civilian occupation or smoking severity. When adjusted for methodological differences, O₂ max was slightly below similar Army entrants in Norway and the United States.     

Interaction between hypercapnic and hypoxic respiratory drive during muscular exertion

During the performance of graded muscular exertion against the background of controlled hypercapnia, hypoxia, hyperoxia, and their combinations, the dynamics of the pulmonary ventilation ( ) and the composition of the alveolar gas (p_a CO₂, p_a O₂) were investigated in 12 healthy men. The respiratory response was assessed from the absolute values of ventilation at a given value of p_a CO₂ and from its increase per mm Hg increase in p_a CO₂ ( ) at rest and on transition to and with establishment of stable conditions of exertion. The respiratory response at the beginning of exertion was accompanied by an upward shift and an increase in the slope of the line, independent of the magnitude of exertion. These changes point to multiplicative ineraction between neurogenic and hypercapnic stimuli with the commencement of exertion. In the steady state of exertion a significant role of the hypoxic stimulus was discovered: During hypoxemia the line was found to be appreciably shifted upward, especially during intensive exertion. This proves that positive interaction between hypercapnic and hypoxic stimuli is potentiated during exertion.Group for Physiology of Respiration, I. P. Pavlov Institute of Physiology, Academy of Medical Sciences of the USSR, Leningrad. (Presented by Academician of the Academy of Sciences of the USSR V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 87, No. 5, pp. 390–393, May, 1979.     

Skeletal muscle determinants of maximum aerobic power in man

Summary The interrelationship between whole body maximum O₂ uptake capacity ( O_{2 max}), skeletal muscle respiratory capacity, and muscle fiber type were examined in 20 physically active men. The capacity of homogenates of vastus lateralis muscle biopsy specimes to oxidize pyruvate was significantly related to O_{2 max} (r=0.81). Correlations of 0.75 and 0.74 were found between % slow twitch fibers (%ST) and O_{2 max}, and between % ST fibers and muscle respiratory capacity, respectively (P<0.01). Multiple correlation analysis (R=0.85) indicated that 72% (R ²=0.72) of the variance in CO_{2 max} could be accounted for by the combined effect of muscle respiratory capacity and the % ST fibers. When the % ST fibers was correlated with O_{2 max}, with the effect of respiratory capacity statistically removed, the relationship became insignificant (r=0.38). These data suggest that muscle respiratory capacity plays an important role in determining O_{2 max}, and that the relationship between % ST fibers and O_{2 max} is due primarily to the high oxidative capacity of this muscle fiber type.This research was supported by NIH grant (HL 20408-02)     

Times to exhaustion at 100% of velocity at\dot V{\text{O}}_{\text{2}} max and modelling of the time-limit / velocity relationship in elite long-distance runners

The aim of this study was to measure running times to exhaustion (Tlim) on a treadmill at 100% of the minimum velocity which elicits _{max max} in 38 elite male long - distance runners _max = 71.4 ± 5.5 ml.kg^–1.min^–1 and _max = 21.8 ± 1.2 km.h^–1). The lactate threshold (LT) was defined as a starting point of accelerated lactate accumulation around 4 mM and was expressed in _max. Tlim value was negatively correlated with _max (r = -0.362, p< 0.05) and _max (r = –0.347, p< 0.05) but positively with LT (%v _max) (r = 0.378, p < 0.05). These data demonstrate that running time to exhaustion at _max in a homogeneous group of elite male long-distance runners was inversely related to _max and experimentally illustrates the model of Monod and Scherrer regarding the time limit-velocity relationship adapted from local exercise for running by Hughson et al. (1984) .     

Maximal aerobic capacity for repetitive lifting: comparison with three standard exercise testing modes

Summary A multi-stage, repetitive lifting maximal oxygen uptake ( ) test was developed to be used as an occupational research tool which would parallel standard ergometric testing procedures. The repetitive lifting test was administered to 18 men using an automatic repetitive lifting device. An intraclass reliability coefficient of 0.91 was obtained with data from repeated tests on seven subjects. Repetitive lifting test responses were compared to those for treadmill, cycle ergometer and arm crank ergometer. The mean±SD repetitive lifting of 3.20±0.42 l · min^–1 was significantly (p<0.01) less than treadmill ( = 0.92 l · min^–1) and cycle ergometer ( = 0.43 l· min^–1) and significantly greater than arm crank ergometer ( = 0.63 l · min^–1). The correlation between repetitive lifting oxygen uptake and power output wasr = 0.65. correlated highly among exercise modes, but maximum power output did not. The efficiency of repetitive lifting exercise was significantly greater than that for arm cranking and less than that for leg cycling. The repetitive lifting test has an important advantage over treadmill or cycle ergometer tests in the determination of relative repetitive lifting intensities. The individual curves of vs. power output established during the multi-stage lifting test can be used to accurately select work loads required to elicit given percentages of maximal oxygen uptake.