• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.2
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• pp.145-151
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• 2006

Because of the limitations of maximal load tests for $VO_2max$, submaximal tests using cycle ergometer are used for field study in general. This study was conducted to evaluate validity of various submaximal tests using cycle ergometer. This study had been conducted during May to June 2005, which subjects were 15 males and 15 females in twenties. Experiment was performed with restrictive conditions which regulated ambient temperature, noise, and entrance restriction. Submaximal load test protocols including YMCA Protocol (YP), ${\AA}strand$-Rhyming Protocol (ARP), Relative heart ratio Protocol (RP), and Ramp test Protocol (RP) were compared with maximal load test which used gas mask analyser using Bruce Protocol. All submaximal load tests were highly related with maximal load test (Spearman's correlation coefficient > 0.60) with statistical significancy. The highest correlation coefficient with maximal test was found in RP. Three submaximal test results except RP were significantly different with maximal test results (Wilcoxon rank test). All submaximal tests had high validity. The reason why RP had highest validity might be that it represents Korean physical strength and individual differences better than the others. RP using cycle ergometer would make easy to study for physical capacity evaluation and field workload estimation.

• Journal of the Korean Society of Safety
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• v.14 no.3
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• pp.174-180
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• 1999

The objective of this study was to investigate the effects of carrying postures and weight of load carried one time on a worker when carrying heavy loads. Six male students participated in this study to perform a manual materials carrying task as subjects. To make comparison of work loads with physical work capacity, maximal oxygen uptake measurement tests were performed with submaximal test. The average oxygen consumption for the tasks of this study was 27.59~31.93% $VO_2$max. The results showed that the weight of load carried one time affects on working heart rate and oxygen consumption($VO_2$). It was found that the workload was significantly lower when handling a 20kg load at a frequency rate of 3times/min than when handling a 40kg load at a frequency rate of 1.5 times/min. There was no difference between carrying postures. It is concluded from the results of this study that the workload can be reduced by controlling conditions of a manual materials handling task.