Continuous Hemodynamic Response to Maximal Dynamic Strength Testing in Older Adults

Abstract

de Vos NJ, Singh NA, Ross DA, Stavrinos TM, Orr R, Fiatarone Singh MA. Continuous hemodynamic response to maximal dynamic strength testing in older adults. Objective To quantify acute changes in blood pressure and heart rate during a maximal dynamic strength—single-repetition maximum lift (1-RM)—testing session in older adults with a low burden of chronic disease. Design Descriptive, cross-sectional study. Setting University rehabilitation center. Participants Volunteer sample of 43 community-dwelling, nonresistance-trained older adults aged 60 years and older (mean, 68±6y). Interventions Not applicable. Main Outcome Measures Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate was obtained by plethysmography at rest and during 1-RM strength testing on leg press, knee extension, and knee flexion resistance machines. Results Average resting SBP (132±28mmHg), DBP (54±15mmHg), and heart rate (65±11 beats/min) were independent of hypertensive diagnosis and overweight status. Maximal SBP, DBP, and heart rate increased significantly during the 1-RM in all exercises compared with rest ( P<.001). Highest values of SBP (236±51mmHg) and DBP (140±46mmHg) were measured during the leg press at 99.5%±6.7% of 1-RM. Lowest values of SBP (79±25mmHg) and DBP (38±15mmHg), and the highest (123±44 beats/min) and lowest heart rate (41±23 beats/min) were measured during the knee extension at 97.4%±8.1% of 1-RM. Absolute falls in SBP were greatest in treated hypertensive participants. No cardiovascular symptoms or events occurred in 129 1-RM tests. Conclusions Large, very transient, asymptomatic excursions in blood pressure and heart rate were measured during 1-RM testing. The most robust hemodynamic response occurred during the leg press. Thus the leg press may be the most important exercise to focus hemodynamic monitoring efforts upon during strength testing in clinical cohorts.