Is it possible to have a single measure for all work?

Metabolic energy expenditure (Vo(2)) is influenced by physical work. The ae robic capacity (Vo(2max)) is frequently used to establish limits on physica l work intensities that workers may-sustain, or operate at, throughout the working day without overexertion. Occasionally, Vo(2max) is also used to es tablish work-rest allowances. With increased automation and supervisory con trol,the physical content of jobs has decreased while mental workload has i ncreased. The cardiovascular system responds to both physical and mental st resses, and their combination, by causing an increase in both the heart rat e and blood pressure, and thereby an increase in myocardial contractility:a nd, consequently, an increase in Myocardial Oxygen Consumption (MVo(2)). We , therefore, believe that MVo(2) is a measure that may be used to establish limits on physical and mental workloads as well as their combinations. It is possible to measure MVo(2) reliably and indirectly by using a non-invasi ve measure called RPP (Rate-Pressure Product). RPP is the product of heart rate and systolic blood pressure. Should future research be able to establi sh the efficacy of MVo(2) as a viable measure of mental and physical worklo ads, it will mean a paradigm change in work measurement research and applic ation..