RESUMEN
BACKGROUND: This study evaluated the energy expenditure of workers in physical work tasks in order to determine if people of different ages and gender carry out repetitive activities according to the recommended limits of energy at work. OBJECTIVE: Exploring whether age is a significant factor to achieve industrial production rates and determine its possible consequences. METHODS: A laboratory experiment was conducted with people age 20 to 58 years split by gender into four age groups. Oxygen consumption and heart rate were measured as variables of response to the physical workloads. RESULTS: When carrying out repetitive moderate load operations, women aged over 30 years exceeded the recommended energy expenditure (95% CI). For heavy activities, only men in the age groups 20-39 and 30-40 years could perform these tasks without exceeding the recommended oxygen consumption (95% CI). CONCLUSIONS: The industrial predetermined motion time systems do not take into account the effects of age and gender difference on energy production when obtaining cycle times in activities with significant aerobic loads. Manufacturing processes have specific standard times that might be inappropriate if they are performed by individuals who do not meet the standard energy production capacity.