Elías Apud¹, Esteban Oñate¹*, Jorge Espinoza¹ and Eduardo Lecannelier²

¹Department of Ergonomics, Faculty of Biological Sciences, University of Concepción, Chile
²Department of Internal Medicine, Faculty of Medicine, University of Concepcion, Chile

*Corresponding Author: Esteban Oñate, Department of Ergonomics, Faculty of Biological Sciences, University of Concepción, Chile.

Received: October 03, 2022; Published: November 11, 2022

Abstract

Mining work in mountainous regions is frequently carried out at altitudes between 3,000 and 5,000 meters above sea level and even higher. Nowadays, there is consensus that subjects, performing identical dynamic physical activities, achieve lower performances at high altitude than at sea level, with equal or greater physical strain. This can be risky for people with chronic diseases, especially respiratory, circulatory, and metabolic conditions. Consequently, the main objective of this study was to evaluate the heart rate in situ of obese workers, who carried out their activities in a mining company, whose tasks are located in a range between 3,700 and 4,200 meters above sea level.
The study was performed in 20 male miners, who carry out different jobs. The sampling was for convenience since the workers were chosen from a group whose body mass index exceeded a value of 30. All of them had medical pass to work at altitude. Follow-ups were done continuously during one shift per miner. Heart rate was measured with POLAR® monitors, simultaneously with time studies. Results showed that 80% of workers under the age of 45 did not exceed recommended limits of physiological load, while in those over 45, 80% reached higher average heart rates than recommended. It was also found that miners were exposed to high peak loads, which in extreme cases exceeded 140 heartbeats per minute. There was a significant correlation between the average heart rate and the peak of heartbeats. A more detailed analysis of two subjects with obesity class II, one with a sedentary job as operator of a frontal end loader and the other carrying out field activities as surveyor assistant, showed statistically significant differences in the physiological response to work.
It is concluded that depending on the type of activity, working at high altitude, may excessively overload the cardiovascular system. Therefore, the prescription of exercise and diet has to be under control of specialists and, in this sense, ergonomics can provide very useful information to understand the impact of work. The approach proposed in this study is laborious, but these miners face daily high-risk tasks carried out in extreme environmental conditions that cannot be modified. Therefore, knowledge of the physiological response, even with basic indicators such as heart rate, is important in ergonomic studies at high altitude, because may help to improve the organization of work to avoid dangerous peak loads.

Keywords: Obesity; Overweight; Heart Rate; Miners; High Altitud

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Citation

Citation: Esteban Oñate., et al. “Physiological Workload of Obese Chilean Miners Working at Altitudes between 3900 and 4200 Meters above Sea Level".Acta Scientific Nutritional Health 6.12 (2022): 53-62.

Copyright

Copyright: © 2022 Esteban Oñate., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.