Can blood pressure decrease after maximal exercise test predict the blood pressure lowering effect of aerobic training in treated hypertensive men?

The acute decrease in blood pressure (BP) observed after a session of exercise (called post-exercise hypotension) has been proposed as a tool to predict the chronic reduction in BP induced by aerobic training. Therefore, this study investigated whether post-exercise hypotension observed after a maximal exercise test is associated to the BP-lowering effect of aerobic training in treated hypertensives. Thirty hypertensive men (50 ± 8 years) who were under consistent anti-hypertensive treatment underwent a maximal exercise test (15 watts/min until exhaustion), and post-exercise hypotension was determined by the difference between BP measured before and at 30 min after the test. Subsequently, the patients underwent 10 weeks of aerobic training (3 times/week, 45 min/session at moderate intensity), and the BP-lowering effect of training was assessed by the difference in BP measured before and after the training period. Pearson correlations were employed to evaluate the associations. Post-maximal exercise test hypotension was observed for systolic and mean BPs (-8 ± 6 and -2 ± 4 mmHg, all P < 0.05). Aerobic training reduced clinic systolic/diastolic BPs (-5 ± 6/-2 ± 3 mmHg, both P < 0.05) as well as awake and 24 h mean BPs (-2 ± 6 and -2 ± 5 mmHg, all P < 0.05). No significant correlation was detected between post-exercise hypotension and the BP-lowering effect of training either for clinic or ambulatory BPs (r values ranging from 0.00 to 0.32, all p > 0.05). Post-exercise hypotension assessed 30 min after a maximal exercise test cannot be used to predict the BP-lowering effect of aerobic training in treated hypertensive men.

Effects of ACEi and ARB on post-exercise hypotension induced by exercises conducted at different times of day in hypertensive men.

BACKGROUND: Post-exercise hypotension (PEH) is greater after evening than morning exercise, but antihypertensive drugs may affect the evening potentiation of PEH. Objective: To compare morning and evening PEH in hypertensives receiving angiotensin-converting enzyme inhibitors (ACEi) or angiotensin II receptor blockers (ARB). METHODS: Hypertensive men receiving ACEi (n = 14) or ARB (n = 15) underwent, in a random order, two maximal exercise tests (cycle ergometer, 15 watts/min until exhaustion) with one conducted in the morning (7 and 9 a.m.) and the other in the evening (8 and 10 p.m.). Auscultatory blood pressure (BP) was assessed in triplicate before and 30 min after the exercises. Changes in BP (post-exercise - pre-exercise) were compared between the groups and the sessions using a two-way mixed ANOVA and considering P < .05 as significant. RESULTS: In the ARB group, systolic BP decrease was greater after the evening than the morning exercise, while in the ACEi group, it was not different after the exercises conducted at the different times of the day. Additionally, after the evening exercise, systolic BP decrease was lower in the ACEi than the ARB group (ARB = -11 ± 8 vs -6 ± 6 and ACEi = -6 ± 7 vs. -8 ± 5 mmHg, evening vs. morning, respectively, P for interaction = 0.014). CONCLUSIONS: ACEi, but not ARB use, blunts the greater PEH that occurs after exercise conducted in the evening than in the morning.

Fase do treinamento esportivo não afeta a variabilidade da frequência cardíaca em atletas de jiu-jitsu / Phase of sports training does affect the heart rate variability in a athletes of jiu-jitsu

O objetivo desse estudo foi avaliar a modulação autonômicacardíaca de atletas de jiu-jitsu, comparando-os com sedentáriose avaliando as alterações dessa modulação ao longo dasdiferentes fases de treinamento. Foram avaliados sete atletas esete indivíduos sedentários do sexo masculino (23 ± 4 e 24 ± 3anos, respectivamente). A frequência cardíaca (FC) e o sinalrespiratório foram coletados por 10 minutos na posição deitadaem três fases do treinamento dos atletas (preparatória, competitivae transitória) e num único momento nos sedentários.A modulação autonômica cardíaca foi avaliada pela análiseespectral da variabilidade da FC (VFC) utilizando-se o modeloautorregressivo. A comparação entre os grupos foi feitapelos testes t não pareado ou Mann-Whitney. A comparaçãoentre as fases de treinamento no grupo de atletas foi realizadapela ANOVA de um fator para amostras repetidas (p < 0,05).Os grupos apresentaram características físicas e funcionaissemelhantes, mas a força máxima foi significantemente maiornos atletas. Todos os índices de VFC foram semelhantes entreos atletas e os sedentários. Além disso, esses índices não sealteraram significantemente entre as fases preparatória, competitivae transitória do treinamento dos atletas. Em conclusão, osatletas de jiu-jitsu apresentam modulação autonômica cardíacasemelhante à de sedentários, e essa modulação não se alteranas diferentes fases de periodização do treinamento.

The aim of this study was to evaluate cardiac autonomic modulationin jiu-jitsu athletes, comparing with sedentary individuals,and evaluating changes that may happen throughout the differentphases of training. Seven athletes and seven sedentary males (23± 4 e 24 ± 3 years, respectively) were evaluated. Heart rate (HR)and respiratory signal were collected for 10 min in the supineposition in the three phases of training (preparatory, competitiveand transient) in the athletes and at one moment in the sedentarysubjects. Cardiac autonomic modulation was evaluated by thespectral analysis of HR variability (HRV) using the autoregressivemodel. Comparisons between groups were performed byunpaired t-test or Mann-Whitney test. Comparisons among thetraining phases were performed by one-way ANOVA for repeatedmeasures (p < 0.05). Athletes and sedentary subjects presentedsimilar physical and cardiovascular characteristics, althoughmaximal strength was significantly higher in the athletes. All ofthe HRV indexes were similar between athletes and sedentarysubjects. In addition, HRV indexes did not change among thepreparatory, competitive and transition phases of training. Inconclusion, jiu-jitsu athletes have cardiac autonomic modulationsimilar to sedentary subjects and this modulation is not changedthroughout the different periodization phases of training.

Absence of parasympathetic reactivation after maximal exercise.

The ability of the human organism to recover its autonomic balance soon after physical exercise cessation has an important impact on the individual's health status. Although the dynamics of heart rate recovery after maximal exercise has been studied, little is known about heart rate variability after this type of exercise. The aim of this study is to analyse the dynamics of heart rate and heart rate variability recovery after maximal exercise in healthy young men. Fifteen healthy male subjects (21·7 ± 3·4 years; 24·0 ± 2·1 kg m(-2) ) participated in the study. The experimental protocol consisted of an incremental maximal exercise test on a cycle ergometer, until maximal voluntary exhaustion. After the test, recovery R-R intervals were recorded for 5 min. From the absolute differences between peak heart rate values and the heart rate values at 1 and 5 min of the recovery, the heart rate recovery was calculated. Postexercise heart rate variability was analysed from calculations of the SDNN and RMSSD indexes, in 30-s windows (SDNN(30s) and RMSSD(30s) ) throughout recovery. One and 5 min after maximal exercise cessation, the heart rate recovered 34·7 (±6·6) and 75·5 (±6·1) bpm, respectively. With regard to HRV recovery, while the SDNN(30s) index had a slight increase, RMSSD(30s) index remained totally suppressed throughout the recovery, suggesting an absence of vagal modulation reactivation and, possibly, a discrete sympathetic withdrawal. Therefore, it is possible that the main mechanism associated with the fall of HR after maximal exercise is sympathetic withdrawal or a vagal tone restoration without vagal modulation recovery.