How accurately are maximal metabolic equivalents estimated based on the treadmill workload in healthy people and asymptomatic subjects with cardiovascular risk factors?

Maeder M, Muenzer T, Rickli H, Brunner-La Rocca H, Myers J, Ammann P. How accurately are maximal metabolic equivalents estimated based on the treadmill workload in healthy people and asymptomatic subjects with cardiovascular risk factors?. International journal of sports medicine 2008; 29:658-63.