A quasi-experimental research was done aiming to compare the effects between the physical workload of the technological intervention and the organization at work of the oven workers who are responsible for the coking coal extraction in Colombia. The physical workload was measured through the heart rate, and the relative cardiac cost among a group of exposed (37), and unexposed workers (66) to a technological intervention. The heart rate monitoring was performed with 7 properly calibrated heart rate monitors Polar RS800CX. The numerical variables were described based on the arithmetic mean, the standard deviation, and the range. The difference among the means of the groups with respect to the resting, average and maximum heart rate, the relative cardiac cost, and the energy expenditure at work was evaluated using the one-way analysis of variance. An a priori statistical significance level α = 0,05 was established in the research. Several statistically significant differences were found out in the behavior of the average heart rate, the maximum heart rate, and the relative cardiac cost within the researched groups. The research has concluded that the heart rate is a valid sensitive variable for measuring the risk of the physical workload, and also, its importance in the evaluation of ergonomic interventions. In addition, this research demonstrated that the technological intervention was able to control the physical workload with an important difference in the heart rate of the intervention group.