warm-up phenomenon

warm-up phenomenon

A clinical finding of an increase in both time to ischaemia and ischaemic threshold in patients with severe angina during an initial effort, which decreases in intensity with subsequent exercise, and is seen after the second (after having “warmed up”) of two sequential exercise tests. The increase to ischaemic threshold is attributed to a mechanism similar to that involved in limiting experimental infarct size following a brief ischaemic episode (i.e., ischaemic preconditioning).

warm-up phe·nom·e·non

(wōrm'ŭp fĕ-nom'ĕ-non)
Progressive diminution of the myotonic response of a muscle during repeated contraction of the muscle.