As the human error causes around 80% of the maritime accidents, the need to optimise mariners’ workload arises as a solution to avoid accidents. Therefore, a methodology to measure workload is developed in which both subjective and objective workload and performance measurements are combined with a secondary task. In research to measure and study workload, knowledge of the distinctiveness of individual properties in physiological measures is of importance. The ability to accurate measure and interpret workload, could also be beneficial to training optimisation. Especially when relating the workload and performance measures to a learning model. This paper presents the results of an experiment to investigate the distribution of personal differences within workload indicators. 56 students participated during a maritime resource management training in a coupled manoeuvring and engine room simulator. The results confirm that simultaneously interpreting several indicators is needed to point out workload, as different components cover different expressions of perceived workload. Next, the individual increase of performance and changes in perceived workload after two and a half days’ training are related to the conscious competence learning model. The workload and performance measures showed that 17 out of 24 students made one or more steps within the learning curve. Based on the perceived workload measurements, 8 of these 17 students did not reach the final unconscious competence level. They would benefit from additional training.