Background: Post-exercise hypotension has been extensively described under laboratory conditions. However, studies investigating the persistence of this post-exercise decrease in blood pressure for longer periods have produced controversial results. The present investigation was conducted to verify the effect of a single bout of exercise on ambulatory blood pressure and to identify potential factors that might influence this post-exercise ambulatory blood pressure fall.
Design: The study was a randomized controlled clinical trial.
Methods: Thirty normotensive and 23 hypertensive subjects were submitted to two ambulatory blood pressure monitorings (using the SpaceLabs 90207, SpaceLabs, Redmond, Washington, USA), which were performed after 45 min of seated rest (control session) or cycling exercise at 50% peak oxygen uptake (exercise session).
Results: Normotensive subjects demonstrated a lower 24 h blood pressure level in the exercise session. Hypertensive patients showed no significant difference in ambulatory blood pressure level between the two experimental sessions. Further data analysis revealed that approximately 65% of the subjects in both groups experienced a fall in blood pressure after exercise. Moreover, in the normotensive subjects, this blood pressure fall was significantly and positively correlated with clinic and ambulatory blood pressure, and negatively correlated with weight and body mass index. The blood pressure response to exercise was also greater in women. In the hypertensive patients, the post-exercise blood pressure decrease was significantly and positively correlated with clinic and ambulatory blood pressure as well as with the peak oxygen uptake, and negatively correlated with age and body mass index.
Conclusions: The post-exercise ambulatory blood pressure fall observed in normotensive and hypertensive humans depends on individual characteristics. Moreover, in both normotensive and hypertensive humans, post-exercise ambulatory hypotension is greater in subjects with a higher initial blood pressure level.
aLaboratory of Exercise Physiology, School of Physical Education and Sports, University of São Paulo, bHypertension Unit, Nephrology Division, Medical School, University of São Paulo, cPathophysiology Department, Medical School, University of São Paulo, dUnit of Cardiac Rehabilitation and Exercise Physiology, InCor-Heart Institute, University of São Paulo, Medical School, São Paulo, Brazil
Correspondence and requests For reprints to Cláudia Lúcia de Moraes Forjaz, PhD, Av. Prof. Mello Moraes, 65-Butantã – São Paulo – SP-05508-900, Brazil. Tel: +55 11 3818-3136; fax: +55 11 3813-5921; e-mail: firstname.lastname@example.org
Received 21 August 2000
Revised 28 September 2000
Accepted 6 October 2000
Presentation: Forjaz CLM, Mion Jr. D, Negrão CE. Factors determining post-exercise hypotension in hypertensive humans. Poster Presentation at the 18th Scientific Meeting of the International Society of Hypertension, Buenos Aires, Argentina, 1999.
Financial support: FAPESP (92/3656-6), CNPq (400146/93-2), Fundação E.J. Zerbini, and Pró-Reitoria de Pesquisa da USP, São Paulo, Brazil.
Potential conflicts of interest: None.