On the reliable assessment of cardiovascular recovery: An application of curve-fitting techniques

The underuse of cardiovascular recovery as an adjunct to reactivity may ste m from a lack of research on how to assess the process reliably. We explore the test-retest reliability of three simple, intuitive approaches to measu ring recovery, and of a more sophisticated curve-fitting technique. Eightee n young normotensive subjects experienced three stressors twice each, with 10-min baseline, 3-min task, and 20-min recovery periods and continuous mon itoring of heart rate and blood pressure. Reactivity showed moderate reliab ility, but the three simple approaches to measuring recovery revealed essen tially none. However, the curve-fitting approach, using a three-parameter ( amount, speed, and level of recovery) logistic function was reliable. This approach, capturing the inherently dynamic process of cardiovascular recove ry, may allow researchers to usefully add the assessment of recovery to par adigms exploring reactivity as a risk factor for cardiovascular disease.