24-h Cardiac Autonomic Profile after Exercise in Sedentary Subjects

Abstract

Most studies regarding the impact of exercise intensity on cardiac autonomic regulation were conducted with athletes and used exercise intensities exceeding those recommended by position stands. We evaluated the influence of exercise intensity in a typical ACSM-aerobic session on 24-h cardiac autonomic modulation in sedentary subjects. Ten healthy sedentary subjects participated in the 3-day study. On 2 days, subjects performed a moderate- or high-intensity aerobic exercise session (MI, HI). The post-exercise protocol consisted of a continuous electrocardiographic recording for 1 h at the laboratory plus 23 h under ambulatory conditions. On the third day 24-h electrocardiographic recording was done without prior exercise (NPE). Heart rate (HR) and frequency-domain parameters (LF, HF) of heart rate variability were evaluated during the entire recovery period. Higher values of HR and lower values of HF and LF were observed throughout the first hour after the HI compared with the MI session. This difference was not observed after in ambulatory awake condition, but reappeared during sleep, when HF values after HI were lower compared with the NPE and MI (p<0.05). Even within the submaximal intensity-range of a typical exercise session, the intensity of exercise influences the post-exercise cardiac autonomic modulation in sedentary subjects.

Heart rate recovery fast‐to‐slow phase transition: Influence of physical fitness and exercise intensity

“…Comparisons of HR recovery between different exercise intensities are laborious. HR at the start of the recovery is greater at higher intensities (Peçanha et al., ), as it can be seen by the greater values of HR i in the HI session. This greater HR i ultimately increases the range of HR decay until the end of recovery in HI session.…”

“…The present study was the first to propose a method to identify the transition of the fast‐to‐slow phase of HR recovery (i.e., HRR PT ). Furthermore, we tested the feasibility of the method by: (1) assessing HRR PT during recovery after HI and MI cycling exercise, which has been previously shown to produce different cardiac autonomic recovery (Pecanha et al., ), and (2) testing the correlations between HRR PT , HRR FP , HRR SP , and physical fitness assessed by VO 2peak . HRR PT was sensitive to exercise intensity, since HI produced greater HRR PT than MI, and partially responsive to aerobic fitness, once the expected correlations between HRR PT and fitness occurred only for MI exercise.…”

“…For this reason, the aim of this study was to propose a method for the identification of fast‐to‐slow phase transition time of HR recovery (HRR PT ) and to test the feasibility of this method by assessing the effects of exercise intensity and physical fitness on HRR PT . Our hypothesis was that HRR PT would be delayed after a high‐intensity exercise (Pecanha et al., ) and would present an inverse relationship with physical fitness (Guerra et al., ).…”

Hipotensão pós-exercício aeróbico e seus mecanismos hemodinâmicos e neurais em pré-hipertensos: influência da fase do dia e associação com a regulação endócrina circadiana

“…Considerando-se a PAD, o exercício hipotensor real do exercício foi semelhante em ambas as fases do dia, o que está de acordo com estudos anteriores que também não observaram diferença nas respostas da PAD após o exercício realizado de manhã ou ao final do dia (BISQUOLO et al, 2005;BRITO et al, 2013;CLEROUX et al, 1992;DUJIC et al, 2006;FLORAS et al, 1989;FORJAZ et al, 2004;FORJAZ et al, 1998a;FORJAZ et al, 1999;FORJAZ et al, 1998b;HAGBERG, MONTAIN & MARTIN, 1987;HEADLEY et al, 1998;HEFFERNAN, COLLIER, KELLY, JAE & FERNHALL, 2007;LACOMBE et al, 2011;LEGRAMANTE et al, 2002;LIU et al, 2012;PECANHA, PRODEL, BARTELS, NASARIO-JUNIOR, PAULA, SILVA, LATERZA & LIMA, 2013;RONDON et al, 2002;SANTANA et al, 2013;SENITKO, CHARKOUDIAN & HALLIWILL, 2002;TEIXEIRA et al, 2011).…”

“…De fato, a permanência de valores elevados da FC pós-exercício comparados ao valor pré-exercício já está bem documentada na literatura (BRITO et al, 2013;FORJAZ et al, 2004;JONES et al, 2007;MCCORD, BEASLEY & HALLIWILL, 2006;PECANHA et al, 2013;SANTANA et al, 2013;TEIXEIRA et al, 2011). Este aumento é normalmente mediado pelo aumento do balanço simpatovagal cardíaco, em consequência da elevação da modulação simpática e/ou redução da modulação parassimpática cardíaca (JAMES, MUNSON, MALDONADO-MARTIN & DE STE CROIX, 2012;LACOMBE et al, 2011;LIU et al, 2012;PECANHA et al, 2013;TEIXEIRA et al, 2011 sugere que a RVP aumenta pela manhã e diminuiu ao final do dia (VOOGEL et al, 2001). A diferença pode se dever à posição sentada adotada no período de recuperação, pois como dito anteriormente, esta posição reduz a pré-carga e desativa o reflexo cardiopulmonar, levando ao aumento da RVP (GIANNATTASIO et al, 1990;GOTSHALL, ATEN & YUMIKURA, 1994;MEKIS & KAMENIK, 2010).…”