The acute effects of exercise modes on pulse wave reflection (PWR) and their relationship with autonomic control remain undefined, particularly in individuals with elevated blood pressure (BP). We ...compared PWR and autonomic modulation after acute aerobic (AE), resistance (RE), and concurrent exercise (CE) in 15 men with stage-1 hypertension (mean ± SE: 34.7 ± 2.5 years, 28.4 ± 0.6 kg/m
, 133 ± 1/82 ± 2 mmHg). Participants underwent AE, RE, and CE on different days in counterbalanced order. Applanation tonometry and heart rate variability assessments were performed before and 30-min postexercise. Aortic pressure decreased after AE (- 2.4 ± 0.7 mmHg; P = 0.01), RE (- 2.2 ± 0.6 mmHg; P = 0.03), and CE (- 3.1 ± 0.5 mmHg; P = 0.003). Augmentation index remained stable after RE, but lowered after AE (- 5.1 ± 1.7%; P = 0.03) and CE (- 7.6 ± 2.4% P = 0.002). Systolic BP reduction occurred after CE (- 5.3 ± 1.9 mmHg). RR-intervals and parasympathetic modulation lowered after all conditions (~ 30-40%; P < 0.05), while the sympathovagal balance increased after RE (1.2 ± 0.3-1.3 ± 0.3 n.u., P < 0.05). Changes in PWR correlated inversely with sympathetic and directly with vagal modulation in CE. In conclusion, AE, RE, and CE lowered central aortic pressure, but only AE and CE reduced PWR. Overall, those reductions related to decreased parasympathetic and increased sympathetic outflows. Autonomic fluctuations seemed to represent more a consequence than a cause of reduced PWR.
The 'verification phase' has emerged as a supplementary procedure to traditional maximal oxygen uptake (VO2max) criteria to confirm that the highest possible VO2 has been attained during a ...cardiopulmonary exercise test (CPET).
To compare the highest VO2 responses observed in different verification phase procedures with their preceding CPET for confirmation that VO2max was likely attained.
MEDLINE (accessed through PubMed), Web of Science, SPORTDiscus, and Cochrane (accessed through Wiley) were searched for relevant studies that involved apparently healthy adults, VO2max determination by indirect calorimetry, and a CPET on a cycle ergometer or treadmill that incorporated an appended verification phase. RevMan 5.3 software was used to analyze the pooled effect of the CPET and verification phase on the highest mean VO2. Meta-analysis effect size calculations incorporated random-effects assumptions due to the diversity of experimental protocols employed. I2 was calculated to determine the heterogeneity of VO2 responses, and a funnel plot was used to check the risk of bias, within the mean VO2 responses from the primary studies. Subgroup analyses were used to test the moderator effects of sex, cardiorespiratory fitness, exercise modality, CPET protocol, and verification phase protocol.
Eighty studies were included in the systematic review (total sample of 1,680 participants; 473 women; age 19-68 yr.; VO2max 3.3 ± 1.4 L/min or 46.9 ± 12.1 mL·kg-1·min-1). The highest mean VO2 values attained in the CPET and verification phase were similar in the 54 studies that were meta-analyzed (mean difference = 0.03 95% CI = -0.01 to 0.06 L/min, P = 0.15). Furthermore, the difference between the CPET and verification phase was not affected by any of the potential moderators such as verification phase intensity (P = 0.11), type of recovery utilized (P = 0.36), VO2max verification criterion adoption (P = 0.29), same or alternate day verification procedure (P = 0.21), verification-phase duration (P = 0.35), or even according to sex, cardiorespiratory fitness level, exercise modality, and CPET protocol (P = 0.18 to P = 0.71). The funnel plot indicated that there was no significant publication bias.
The verification phase seems a robust procedure to confirm that the highest possible VO2 has been attained during a ramp or continuous step-incremented CPET. However, given the high concordance between the highest mean VO2 achieved in the CPET and verification phase, findings from the current study would question its necessity in all testing circumstances.
CRD42019123540.
ABSTRACTFonseca, GF, Farinatti, PTV, Midgley, AW, Ferreira, A, de Paula, T, Monteiro, WD, and Cunha, FA. Continuous and accumulated bouts of cycling matched by intensity and energy expenditure elicit ...similar acute blood pressure reductions in prehypertensive men. J Strength Cond Res 32(3)857–866, 2018—This study investigated differences in postexercise hypotension (PEH) after continuous vs. accumulated isocaloric bouts of cycling. Ten prehypertensive men, aged 23–34 years, performed 2 bouts of cycling at 75% oxygen uptake reserve, with total energy expenditures of 400 kcal per bout. One exercise bout was performed continuously (CONTIN) and the other as 2 smaller bouts each expending 200 kcal (INTER1 and INTER2). Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and cardiac autonomic control were monitored in a supine position for 10 minutes before and 60 minutes after each exercise bout, and during a control session. Compared with control, blood pressure was significantly reduced after CONTIN (SBPINCREMENT − 3.4 mm Hg, p < 0.001; MAPINCREMENT − 2.5 mm Hg, p = 0.001), INTER1 (SBPINCREMENT − 2.2 mm Hg, p = 0.045), and INTER2 (SBPINCREMENT − 4.4 mm Hg, p < 0.001; DBPINCREMENT − 2.7 mm Hg, p = 0.045; MAPINCREMENT − 3.3 mm Hg, p = 0.001). The PEH was similar in CONTIN and INTER2, whereas INTER2 elicited greater PEH than INTER1 (SBP and MAPINCREMENT − 2.0 and INCREMENT − 1.8 mm Hg, respectively, p ≤ 0.05). Increases in sympathovagal balance from baseline were inversely related to changes in SBP and DBP after CONTIN and INTER2 (r = −0.64 to −0.71; p = 0.021–0.047). These findings indicate that similar amounts of PEH are observed when exercise is performed as a single 400-kcal exercise bout or 2 × 200-kcal bouts and that the exercise recovery pattern of cardiac autonomic activity may be important in eliciting PEH.
Abstract Aim: Spinal cord injury (SCI) is associated with changes in cardiac autonomic control, that can be evaluated by heart rate variability (HRV), for which the electrocardiogram (ECG) is the ...gold standard. However, the use of ECG is limited to laboratory environments, and new tools are needed for this purpose and that can be applied in the routine monitoring of individuals with SCI. The present study aimed to investigate the validity of the Polar V800 heart rate monitor in assessing the cardiac autonomic control of individuals with SCI. Methods: Nineteen adult men with SCI (paraplegia n = 10; 44.5 ± 8.5 years and tetraplegia n = 9; 34.4 ± 7.5 years) participated in this cross-sectional study. The participants remained in the sitting position at rest for 10 min for the acquisition of the ECG and Polar V800 signals. The last 5-min window was used to count the beat-by-beat R-R interval series and then calculate the HRV indices (linear methods in the time and frequency domains). The study subgroups were compared, and the validity of the measurements generated with a heart rate monitor was determined using the intraclass correlation coefficient (ICC2,1) and Bland-Altman graphs. Results: Agreement analyses for the R-R intervals, SDNN, rMSSD, PNN50, SD1, LF, HF, and LF: HF ratio tended to show reliability ranging from acceptable to excellent (ICC = 0.579-0.990; P = 0.043-0.001) and acceptably narrow limits of agreement within both the group with tetraplegia and the group with paraplegia. Conclusion: The Polar V800 heart rate monitor is a valid instrument for assessing HRV in individuals with paraplegia and tetraplegia.
In recent years, it has become more evident that oxidative stress is involved in the development of cardiovascular disease. Indeed, reactive oxygen species seems to be the common mechanism for ...endothelial dysfunction, vascular inflammation and arterial stiffness, resulting in a blood pressure increase and early vascular aging.
This review presents the potential role of antioxidant nutrients and exercise for cardiovascular protection.
Flavonoids, vitamins and minerals present in some fruits and foliage are considered natural antioxidants. In fact, fruits and vegetables contain large amounts of antioxidants. Several clinical trials have extensively studied vitamin E, beta-carotene, vitamin C, polyphenols, plus selenium and zinc. In addition, many authors have been carried out clinical trials to evaluate the mechanisms of oxidative stress attenuation after exercise. Exercise responses may vary according to the Frequency, Intensity, Time and Type (FITT) principle, making it difficult to obtain a consensus concerning the exercise properties and redox status. High-intensity interval training (HIIT) has been reported as an efficient option for metabolic adaptations in a short time. Aerobic exercises must be performed at least three times a week, for two months or more, using moderate to vigorous intensity to promote a positive effect on oxidative stress and vascular function.
The recognition of appropriate nutrients and exercise with antioxidant properties may be an important supportive approach to impair early vascular aging and to prevent cardiovascular disease.
This study aims to investigate the effects of acute cycling on blood pressure (BP), arterial function, and heart rate variability (HRV) in men living with HIV (MLHIV) using combined antiretroviral ...therapy (cART).
Twelve MLHIV (48.7 ± 9.2 years; 25.2 ± 2.8 kg m
) and 13 healthy controls (41.2 ± 9.9 years; 26.3 ± 2.9 kg m
) performed a cycling bout (ES) (intensity: 50% oxygen uptake reserve; duration: time to achieve 150 kcal-MLHIV: 24.1 ± 5.5 vs. controls: 23.1 ± 3.0 min;
= 0.45), and a 20-min non-exercise session (NES).
At rest (
< 0.05), MLHIV presented higher brachial systolic/diastolic BP (SBP/DBP: 123.2 ± 14.2/76.8 ± 6.3 vs. 114.3 ± 5.1/71.6 ± 2.6 mmHg) and central BP (cSBP/cDBP: 108.3 ± 9.3/76.5 ± 6.5 vs. 101.6 ± 4.9/71.3 ± 4.4 mmHg) vs. controls but lower absolute maximal oxygen uptake (2.1 ± 0.5 vs. 2.5 ± 0.3 L min
) and HRV indices reflecting overall/vagal modulation (SDNN: 24.8 ± 7.1 vs. 42.9 ± 21.3 ms; rMSSD: 20.5 ± 8.5 vs. 38.1 ± 22.8 ms; pNN50: 3.6 ± 4.2 vs. 13.6 ± 11.3%). DBP postexercise lowered in controls vs. MLHIV (∼4 mmHg,
< 0.001; ES: 0.6). Moreover, controls vs. MLHIV had greater reductions (
< 0.05) in augmentation index (-13.6 ± 13.7 vs. -3.1 ± 7.2% min
; ES: 2.4), and HRV indices up to 5 min (rMSSD: -111.8 ± 32.1 vs. -75.9 ± 22.2 ms min
; ES: 3.8; pNN50: -76.3 ± 28.3 vs. -19.0 ± 13.7% min
; ES: 4.4). Within-group (ES vs. NES;
< 0.05) reductions occurred in controls for SBP (∼10 mmHg, 2 h), DBP (∼6 mmHg, 20, 30, and 70 min), cSBP (∼9 mmHg, 30 min), cDBP (∼7 mmHg, 30 and 70 min), augmentation index (∼10%, 30 min), and pNN50 (∼20%; up to 2 h), while in MLHIV only cSBP (∼6 mmHg, 70 min) and cDBP (∼4 mmHg, 30 min) decreased. Similar increases (up to 5 min) in heart rate (∼22 bpm) and decreases in SDNN (∼18 ms) and rMSSD (∼20 ms) occurred in both groups.
MLHIV under cART exhibited attenuated postexercise hypotension vs. healthy controls, which seemed to relate with impairments in vascular function.
Institutional position stands are useful for practitioners when designing exercise routines for specific populations. Resistance training has been included in programs for patients with ...cardiovascular disease.
The objective of this systematic review was to analyze institutional guidelines providing recommendations for resistance training applied to cardiovascular disease.
PubMed, Web of Science, and Scopus databases were searched from inception until 30 April, 2018.
Of 994 articles initially found, 13 position stands were retained. Consensual indications occurred only for number of sets (one to three sets) and training frequency (two to three sessions/week). Recommendations concerning other major training variables were discordant regarding workload (none or loads ranging from < 30% up to 80% 1 repetition maximum) and exercise order (none or vaguely indicating alternation of muscle groups or circuit format), or insufficient regarding intervals between sets and exercises or number and type of exercises. Overall, guidelines lack recommendations of specific procedures for each type of disease at different severity levels, cardiovascular risk during exercise, or criteria for training progression.
Recommendations provided by institutional guidelines appear to be insufficient to support adequate resistance training prescription in the context of cardiovascular disease.
ABSTRACTde Paula, T, Neves, MF, da Silva Itaborahy, A, Monteiro, W, Farinatti, P, and Cunha, FA. Recovery pattern of cardiac autonomic control after aerobic and strength exercises in overweight ...prehypertensive men. J Strength Cond Res 33(10)2743–2752, 2019—The extent to which postexercise cardiac autonomic control depends on exercise modality remains unclear, particularly among individuals with autonomic dysfunction (cardiac autonomic dysfunction CADysf). This study compared heart rate variability (HRV) and baroreflex sensitivity (BRS) responses to acute aerobic exercise (AE) and strength exercise (SE) in men with CADysf. Twenty men were assigned into control (n = 1033.8 ± 3.0 years; 23.7 ± 1.5 kg·m) and CADysf (n = 1036.2 ± 9.8 years; 28.4 ± 2.6 kg·m) groups. Cardiac autonomic dysfunction underwent AE, SE, and a nonexercise control day (control session CTL) in a randomized, counter-balanced order. Heart rate variability and BRS were assessed in a supine position during 25 minutes of recovery after AE, SE, and CTL. Both HRV indices (p ≤ 0.05; effect size Cohenʼs d>1.4) and BRS at rest were significantly lower in CADysf than those in controls (p < 0.01; effect size Cohenʼs d≥1.36). In CADysf, postexercise increases in heart rate, sympathetic activity (low-frequency LF band), and sympathovagal balance (LF:high-frequency HF ratio), as well as decreases in R-R interval, parasympathetic activity (HF band), and BRS were observed in AE (p ≤ 0.05; effect size Cohenʼs d≥1.31) and SE (p ≤ 0.05; effect size Cohenʼs d≥0.79) vs. CTL, but changes were larger after AE than SE (p ≤ 0.05; effect size Cohenʼs d≥0.73). In conclusion, both AE and SE elicited postexercise changes in HRV and BRS among CADysf men, primarily reflected by lowered vagal modulation, increased sympathovagal balance, and a delayed BRS recovery pattern. However, those changes seem to be more likely to occur after AE than SE.
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