Post-resistance exercise hemodynamic and autonomic responses: Comparison between normotensive and hypertensive men A. C. C. Queiroz 1 , J. C. S. Sousa 1 , A. A. P. Cavalli 1 , N. D. Silva Jr 1 , L. A. R. Costa 1 , E. Tobaldini 2 , N. Montano 2 , G. V. Silva 3 , K. Ortega 3 , D. Mion Jr 3 , T. Tinucci 1,3 , C. L. M. Forjaz 1 1 Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo, São Paulo, Brazil, 2 Department of Biomedical and Clinical Sciences “L. Sacco”, Medicine and Physiopathology, L. Sacco Hospital, University of Milan, Milan, Italy, 3 Hypertension Unit, General Hospital, University of São Paulo, São Paulo, Brazil Corresponding author: Andréia Cristiane Carrenho Queiroz, PhD, Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo, Av. Prof. Mello Moraes, 65 Butantã, São Paulo, SP 05508-030, Brazil. Tel: +55 11 30918792, Fax: +55 11 38135921, E-mail: andreiaqueiroz@usp.br Accepted for publication 28 May 2014 To compare post-resistance exercise hypotension (PREH) and its mechanisms in normotensive and hypertensive individuals, 14 normotensives and 12 hypertensives underwent two experimental sessions: control (rest) and exercise (seven exercises, three sets, 50% of one repetition maximum). Hemodynamic and autonomic clinic mea- surements were taken before (Pre) and at two moments post-interventions (Post 1: between 30 and 60 min; Post 2: after 7 h). Ambulatory blood pressure (BP) was moni- tored for 24 h. At Post 1, exercise decreased systolic BP similarly in normotensives and hypertensives (-8 ± 2 vs -13 ± 2 mmHg, P > 0.05), whereas diastolic BP decreased more in hypertensives (-4 ± 1 vs -9 ± 1 mmHg, P < 0.05). Cardiac output and systemic vascular resistance did not change in normotensives and hypertensives (0.0 ± 0.3 vs 0.0 ± 0.3 L/min; -1 ± 1 vs -2 ± 2 U, P > 0.05). After exer- cise, heart rate (+13 ± 3 vs +13 ± 2 bpm) and its variabil- ity (low- to high-frequency components ratio, 1.9 ± 0.4 vs +1.4 ± 0.3) increased whereas stroke volume (-14 ± 5 vs -11 ± 5 mL) decreased similarly in normotensives and hypertensives (all, P > 0.05). At Post 2, all variables returned to pre-intervention, and ambulatory data were similar between sessions. Thus, a session of resistance exercise promoted PREH in normotensives and hyperten- sives. Although this PREH was greater in hypertensives, it did not last during the ambulatory period, which limits its clinical relevance. In addition, the mechanisms of PREH were similar in hypertensives and normotensives. Hypertension is a very prevalent chronic disease and considered one of the most important risk factors for cardiovascular disease (Chobanian et al., 2003). Aerobic exercise is recommended for the treatment of hyperten- sives, and nowadays resistance exercise has been added to this recommendation as an adjunct therapy (Williams et al., 2007; American College of Sports Medicine, 2010). A single session of aerobic or resistance exercise reduces blood pressure (BP) during the recovery period, which is called post-exercise hypotension. To be clini- cally significant, however, this BP reduction should have an important magnitude and should last for many hours after the end of the exercise (Kenney & Seals, 1993). Post-resistance exercise hypotension (PREH) has been extensively reported in normotensive subjects (Rezk et al., 2006; Moraes et al., 2007; Queiroz et al., 2009, 2013b; Teixeira et al., 2011). The magnitude of systolic/diastolic BP reductions after resistance exercise in these individuals varies from -4/-2 to -14/-4 mmHg. In regard to the duration of PREH in normotensives, most of the studies reported significant decreases for 60–90 min after the exercise, but a decrease on post-resistance exercise ambulatory BP has not been observed (Queiroz et al., 2009). Nevertheless, studies point out that BP reduction after a resistance exercise session is greater in subjects with higher pre-exercise BP (Queiroz et al., 2009). Studies in patients with hypertension have reported reductions of systolic/diastolic BP of -12/-6 to -23/-14 mmHg (Hardy & Tucker, 1998; Melo et al., 2006; Moraes et al., 2007, 2012). These reductions may be sustained up to 10 h during ambulatory conditions (Melo et al., 2006). Together, these results suggest that PREH should be greater and last longer in hypertensives than normoten- sives. However, to our knowledge, no study has com- pared PREH magnitude and duration between these subjects after the same exercise session. Hemodynamic and autonomic determinants of PREH have been investigated in normotensives but not in hypertensives. In normotensives, BP reduction was attributed to a decrease in cardiac output (CO) promoted by a reduction in stroke volume (SV) and not accompa- nied by an increase in systemic vascular resistance (SVR) (Teixeira et al., 2011). The decrease in CO Scand J Med Sci Sports 2014: ••: ••–•• doi: 10.1111/sms.12280 © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd 1