Effects of high-intensity interval and continuous moderate aerobic training on fitness and health markers of older adults: A systematic review and meta-analysis.

BACKGROUND: High-intensity interval training (HIIT) promotes similar or superior gains in physical fitness and health compared to continuous moderate-intensity training (MICT) in young individuals. However, the effectiveness of HIIT in older adults is uncertain. OBJECTIVE: This meta-analysis compared the effects of HIIT and MICT on cardiorespiratory fitness, body composition, vascular, metabolic, and hormonal variables, cognitive function, and quality of life in older adults. METHODS: PubMed, Embase, Cochrane, Web of Science, Scopus, and SportDiscus databases were searched from inception until December 2023. Trials included adults ≥ 60 y. Hedge's effect sizes (g) were calculated and study quality and features of training interventions were tested as moderators. RESULTS: Twenty-nine trials including 1,227 subjects (65.4 ± 3.3 y). HIIT and MICT elicited significant (p < 0.021) and similar (p > 0.156) 'gs' for VO2max (0.722 vs. 0.490), maximal workload/peak power output ratio (0.290 vs. 0.372),% fat (-0.297 vs. -0.262), glycemia (-0.273 vs. -0.334), systolic (-0.465 vs. -0.341), and diastolic blood pressure (-0.566 vs. -2.311). HIIT (p < 0.04) but not MICT (p > 0.170) produced significant 'gs' for fat mass (-0.245 vs. -0.103), waist circumference (-0.239 vs. -0.116), testosterone (0.339 vs. 0.170), and complex Stroop test (-0.595 vs. -0.250). Increases in the VO2max occurred only in controlled trials after HIIT but not MICT (Q = 6.286, p = 0.012; HITT-g = 1.068, p < 0.0001 vs. MICT-g = 0.109, p= 0.596). CONCLUSION: HIIT and MICT produced similar changes in most of the investigated variables. In trials with greater quality (controlled vs. non-controlled trials), cardiorespiratory gains were higher in HIIT vs. MICT. These findings suggest that HIIT might be suitable for improving fitness and health in older adults.

Effects of Isocaloric Resistance, Aerobic, and Concurrent Exercise on Excess Postexercise Oxygen Consumption in Older Adults.

ABSTRACT: Pilon, R, Matos-Santos, L, Matlez, MP, Rodrigues, G, Amorim, F, Lattari, E, Farinatti, P, and Monteiro, W. Effects of isocaloric resistance, aerobic, and concurrent exercise on excess postexercise oxygen consumption in older adults. J Strength Cond Res 38(4): 755-761, 2024-Excess postexercise oxygen consumption (EPOC) is a major determinant of exercise-related caloric expenditure and metabolic adaptations. Exercise modality may influence the EPOC, but this issue has not been investigated in older adults. This study compared the EPOC after isocaloric bouts of continuous aerobic exercise (AE), resistance exercise (RE), and concurrent exercise (CE) in older individuals. Ten subjects (5 men; 73 ± 6 years) had their cardiorespiratory data assessed during AE, RE, and CE and along 30-minute postexercise recovery. Total energy expenditure (EE) during exercise was similar (p > 0.05) in AE (126.0 ± 30.7 kcal), RE (123.9 ± 30.6 kcal), and CE (130.8 ± 32.6 kcal), with different times to achieve the targeted EE (RE: 61.4 ± 1.9 minutes > CE: 43.3 ± 5.6 minutes > AE: 26.6 ± 5.7 minutes; p < 0.001). Consistently, the relative intensity during exercise was superior (p < 0.05) in AE (74 ± 15% oxygen uptake reserve [VO2R]) vs. CE (43 ± 13% VO2R) vs. RE (24 ± 9% VO2R). Despite the isocaloric conditions, average EPOC and EE were approximately 45% greater (p < 0.001) in AE (8.0 ± 2.3 L; 40.1 ± 11.7 kcal) vs. RE (5.6 ± 1.2 L; 28.1 ± 5.8 kcal) and CE (5.4 ± 2.3 L; 26.9 ± 11.5 kcal). In conclusion, the EPOC was greater after isocaloric AE vs. RE and CE performed by older adults. Exercise intensity seemed to be a more important determinant of EPOC than volume reflected by EE during exercise bouts. Moderate-intensity continuous AE was more time-efficient than RE and CE to achieve a target EE. In older individuals, AE should be preferred over RE or CE when the purpose is to increase the daily caloric expenditure.

Excess Postexercise Oxygen Consumption Following Isocaloric Bouts of Resistance and Aerobic Exercise in Older Adults.

Purpose: Albeit being a major determinant of exercise-related energy expenditure (EE), there is a lack of research on the excess post-exercise oxygen consumption (EPOC) after different exercise modalities in older adults. This study compared the EPOC after isocaloric bouts of resistance (RE) and aerobic (AE) exercise. Methods: The EE during exercise was determined through telemetric indirect calorimetry in ten physically active participants aged 63 to 82 years (5 women, 73 ± 6 years, 70.5 ± 9.9 kg, 161 ± 8 cm). The target EE in AE corresponded to values achieved during RE, and the EPOC was assessed for 30 min in the supine position. Results: The EE during AE and RE were 126.0 ± 30.7 kcal and 123.9 ± 30.6 kcal, respectively. The time to achieve the target EE was 2.3 times shorter in AE vs. RE. The EPOC magnitude was greater after AE (7.9 ± 2.4 L, 40.1 ± 11.1 kcal) than RE (5.9 ± 1.8 L, 26.9 ± 11.5 kcal). Conclusion: Older adults showed greater EPOC after isocaloric sessions of AE vs. RE. Additionally, AE had better temporal efficiency than RE to elicit a given EE.

Postactivation performance enhancement in the vertical jump using loads above or below the optimum-power load for a jump squat.

BACKGROUND: Postactivation performance enhancement (PAPE) is an acute response of increased muscle performance following a conditioning activity (CA), generally prescribed based on the percentage of a one-repetition maximum. However, it is unknown how the PAPE response is affected when the CA is performed near the optimum power zone. The purpose of this study was to examine PAPE using loads that were 20% above or below the optimum-power load (OPL). METHODS: Fifteen recreationally trained subjects, with at least one-year resistance training experience participated in this study. First, the OPL for the JS was determined. Then, subjects performed two protocols in a counterbalanced order: 20% above (+20%OPL) or below (-20%OPL). To examine PAPE on performance, the vertical jump was performed prior to and seven times following each jump squat protocol, with a 2-min rest interval between trials. RESULTS: The two-way ANOVA revealed main effects for condition (F=4.978; P<0.001) for jump height and jump power (F=2.589; P=0.017), but post-hoc comparisons did not show differences. Between baseline and the best trial following each jump squat protocol, two-way ANOVA did not reveal main effects (F=3.048; P=0.103) or interactions (F=0.304; P=0.590). Paired t-tests did not show significant differences between conditions for relative changes in jump height (P=0.543) or jump power (P=0.233). CONCLUSIONS: This study revealed similar results between 20% above or below the OPL on subsequent vertical jump performance.

Self-selected or fixed: is there an optimal rest interval for controlling intensity in high-intensity interval resistance training?

PURPOSE: This study investigated the effects of different rest interval strategies during high-intensity interval resistance training (HIRT) on cardiorespiratory, perceptual, and enjoyment responses among trained young men. METHODS: Sixteen men experienced with HIRT underwent cardiopulmonary exercise testing and were familiarized with the exercises and HIRT protocol. On the subsequent three visits, interspaced 48-72 h, participants performed HIRT sessions with different rest intervals in a randomized order: 10 s and 30 s fixed rest intervals (FRI-10 and FRI-30), and self-selected rest interval (SSRI). Oxygen uptake (VO2), heart rate (HR), and recovery perception (Total Quality Recovery Scale) were measured during HIRT, while enjoyment responses (Physical Activity Enjoyment Scale) were assessed immediately after the sessions. RESULTS: The VO2 during exercise was greater in FRI-10 than FRI-30 (55% VO2max and 47% VO2max, respectively, p = 0.01), while no difference occurred between SSRI and bouts performed with fixed intervals (52% VO2max vs. FRI, p > 0.05). HR, excess post-exercise oxygen consumption (EPOC), recovery perception, and enjoyment responses were similar across conditions (p > 0.05). CONCLUSION: Exercise intensity was not affected by the rest interval strategy. High exercise intensity was maintained in sessions performed with FRI or SSRI, without negative repercussions on the duration of training sessions and enjoyment responses after exercise sessions.

Effects of physical activity on body mass and composition of school-age children and adolescents with overweight or obesity: Systematic review focusing on intervention characteristics.

OBJECTIVE: The characteristics of physical activity (PA) interventions to improve body mass and composition in pediatric populations are unclear. This systematic review summarized the effects of PA on those outcomes in school-age children and adolescents with overweight or obesity, focusing on training components (frequency, intensity, duration, and type - FITT). METHODS: Databases were searched for controlled trials applying exclusive PA and including children (5-12 y) or adolescents (13-17 y) with overweight/obesity. RESULTS: Twenty-seven trials yielding 34 interventions were included. PA was recreational (children: k = 9, n = 478), systematized (children: k = 18, n = 565); or combined (children: k = 7, n = 205). Successful interventions were performed for 6- to 35 weeks (mostly 12-14 weeks), 2- to 5 d/wk (mostly 3 d/wk), during 8- to 60 min (mainly 60 min) with moderate to high intensity (60-90% maximal heart rate or 40-70% heart rate reserve). Half of the interventions applying recreational (4 out of 8), 59% of systematized (10 out of 17), and 57% of combined (4 out of 7) interventions reported improvements in body mass or composition, especially body fat. Benefits were more often reported for body composition (18 out of 34 interventions) than body mass (8 out of 34 interventions), irrespective of the age group. CONCLUSION: Recreational and systematized PA may improve body mass, and particularly body composition in school-age children and adolescents with overweight or obesity. Successful programs were performed for at least six weeks and applied a PA amount consistent with the minimum recommended for pediatric populations (≥60 min of moderate-to-vigorous PA at least 3 d/wk).

Influence of HIIRT With Fixed and Self-Selected Recovery Intervals on Physiological, Affective, and Enjoyment Responses.

Purpose: Recovery-interval strategies may influence physiological and psychological responses during highintensity interval resistance training (HIIRT). This study compared the intensity, performance, and psychological outcomes during all-out effort HIIRT performed with fixed (FRI) and self-selected (SSRI) recovery intervals. Methods: Sixteen trained males (27.2 ± 4.1 years; 84.5 ± 8.9 kg; 55.8 ± 7.1 mL.kg-1.min-1) performed HIIRT bouts interspersed with FRI (10 s) and SSRI (15.3 ± 7.9 s). Results: Relative heart rate (%HRmax) and oxygen uptake (%VO2Peak), number of repetitions, and psychological responses (affection: Feeling ScaleFS; Felt Arousal ScaleFAS; enjoyment: Physical Activity Enjoyment ScalePACES) were assessed. FRI and SSRI elicited similar relative average intensity (p > .05) (%HRmax: 88.1 ± 3.5% vs. 87.6 ± 3.0%; %VO2Peak: 55.3 ± 7.4% vs. 54.1 ± 8.1%, respectively). The number of repetitions similarly decreased in SSRI and FRI from rounds 1 to 4 (~15%; p < .006), with no difference of total volume across conditions (FRI: 358.6 ± 32 reps vs. SSRI:357.5 ± 28.2; p = .89). In each round, no difference between FRI and SSRI (p > .05) was found for FS (3- to 3.5 vs. 2- to 4, respectively) or FAS (2- to 4 vs. 2- to 4, respectively), while PACES was lower in FRI than SSRI (102.8 ± 15.8 vs. 109.2 ± 13.2; p = .04). Conclusion: In conclusion, relative intensity, total repetitions, and affective perception were not influenced by the strategy of recovery intervals. On the other hand, overall enjoyment was favored in SSRI vs. FRI.

Anodal Transcranial Direct Current Stimulation Does Not Affect Velocity Loss During a Typical Resistance Exercise Session.

Purpose: This study investigated the effects of transcranial direct current stimulation (tDCS) on velocity loss in a typical resistance exercise session. Methods: Twelve recreationally resistance-trained males (age = 24.8 ± 3.0 years, body mass = 78.9 ± 13.6 kg, and height = 174.3 ± 7.3 cm) completed two experimental trials in a counterbalanced crossover design: anodal tDCS and sham conditions. The stimuli were applied over the left dorsolateral prefrontal cortex for 20 minutes, using a 2 mA current intensity in anodal tDCS and a 1-minute active stimulus in the sham condition. After stimulation, subjects performed three sets of the bench press at a 70% of 1 maximum repetition intensity and 1 min of inter-set rest. The velocity loss was calculated as the relative difference between the fastest repetition velocity (usually first) and the velocity of the last repetition of each set and averaged over all three sets. Results: The results found no interaction between conditions and sets (P = .122), and no effect for conditions (P = .323) or sets (P = .364) for the velocity loss in each set. Also, no differences were found between the average velocity loss of the three sets in the anodal tDCS (-25.0 ± 4.7%) and sham condition (-23.3 ± 6.4%; P = .323). Conclusion: Anodal tDCS does not affect movement velocity in a typical strength training protocol in recreationally trained subjects.

Are Self-Selected Intervals as Effective as Fixed Intervals in Controlling Acute Responses in High-Intensity Interval Resistance Training?

Physical conditioning programs often apply high-intensity resistance training (HIRT), but there is a lack of research investigating the effects of using fixed or self-selected resting intervals between exercises on the performance, relative intensity, and affective perception during this modality of training. This study compared fixed versus self-selected rest intervals in HIRT sessions on cardiorespiratory responses, number of repetitions, and enjoyment perception in trained young men. Sixteen trained males (27.1 ± 3.9 years; 56.6 ± 7.5 mL.kg-1.min-1) performed HIRT circuits with 30-s and self-selected recovery interval. The duration of resting intervals was longer in HIRT performed with fixed than self-selected intervals (14.04 ± 5.82 s; p < 0.0001; ES = 3.2). Both sessions elicited similar relative HRR (79.4 ± 6.2 % vs. 81.6 ± 4.2 %; p = 0.14), VO2R (43.0 ± 12.2% vs. 47.7 ± 9.6%; p = 0.10), and enjoyment reflected by scores in the PACES questionnaire (107.9 ± 15.1 vs. 109.2 ± 12.8; p = 0.65). The total number of repetitions (403.4 ± 45.5 vs. 353.1 ± 27.4; p < 0.01, ES = 1.3) and caloric expenditure (154.4 ± 28.6 kcal vs. 121.4 ± 21.6 kcal; p < 0.001, ES = 0.13) were greater in HIRT performed with fixed vs. self-selected intervals. In conclusion, HIRT performed with fixed and self-selected rest intervals elicited similar relative intensity and enjoyment perception. However, the number of repetitions and caloric expenditure were greater in sessions performed with fixed 30-s.

Acute effects of mixed circuit training on hemodynamic and cardiac autonomic control in chronic hemiparetic stroke patients: A randomized controlled crossover trial.

Objectives: To investigate whether a single bout of mixed circuit training (MCT) can elicit acute blood pressure (BP) reduction in chronic hemiparetic stroke patients, a phenomenon also known as post-exercise hypotension (PEH). Methods: Seven participants (58 ± 12 years) performed a non-exercise control session (CTL) and a single bout of MCT on separate days and in a randomized counterbalanced order. The MCT included 10 exercises with 3 sets of 15-repetition maximum per exercise, with each set interspersed with 45 s of walking. Systolic (SBP) and diastolic (DBP) blood pressure, mean arterial pressure (MAP), cardiac output (Q), systemic vascular resistance (SVR), baroreflex sensitivity (BRS), and heart rate variability (HRV) were assessed 10 min before and 40 min after CTL and MCT. BP and HRV were also measured during an ambulatory 24-h recovery period. Results: Compared to CTL, SBP (∆-22%), DBP (∆-28%), SVR (∆-43%), BRS (∆-63%), and parasympathetic activity (HF; high-frequency component: ∆-63%) were reduced during 40 min post-MCT (p < 0.05), while Q (∆35%), sympathetic activity (LF; low-frequency component: ∆139%) and sympathovagal balance (LF:HF ratio: ∆145%) were higher (p < 0.001). In the first 10 h of ambulatory assessment, SBP (∆-7%), MAP (∆-6%), and HF (∆-26%) remained lowered, and LF (∆11%) and LF:HF ratio (∆13%) remained elevated post-MCT vs. CTL (p < 0.05). Conclusion: A single bout of MCT elicited prolonged PEH in chronic hemiparetic stroke patients. This occurred concurrently with increased sympathovagal balance and lowered SVR, suggesting vasodilation capacity is a major determinant of PEH in these patients. This clinical trial was registered in the Brazilian Clinical Trials Registry (RBR-5dn5zd), available at https://ensaiosclinicos.gov.br/rg/RBR-5dn5zd. Clinical Trial Registration: https://ensaiosclinicos.gov.br/rg/RBR-5dn5zd, identifier RBR-5dn5zd.

The Effects of Acute Aerobic Exercise on Blood Pressure, Arterial Function, and Heart Rate Variability in Men Living With HIV.

PURPOSE: 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). METHODS: Twelve MLHIV (48.7 ± 9.2 years; 25.2 ± 2.8 kg m-2) and 13 healthy controls (41.2 ± 9.9 years; 26.3 ± 2.9 kg m-2) 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; p = 0.45), and a 20-min non-exercise session (NES). RESULTS: At rest (p < 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-1) 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, p < 0.001; ES: 0.6). Moreover, controls vs. MLHIV had greater reductions (p < 0.05) in augmentation index (-13.6 ± 13.7 vs. -3.1 ± 7.2% min-1; ES: 2.4), and HRV indices up to 5 min (rMSSD: -111.8 ± 32.1 vs. -75.9 ± 22.2 ms min-1; ES: 3.8; pNN50: -76.3 ± 28.3 vs. -19.0 ± 13.7% min-1; ES: 4.4). Within-group (ES vs. NES; p < 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. CONCLUSION: MLHIV under cART exhibited attenuated postexercise hypotension vs. healthy controls, which seemed to relate with impairments in vascular function.

Postexercise hypotension due to resistance exercise is not mediated by autonomic control: A systematic review and meta-analysis.

Changes in autonomic control have been suggested to mediate postexercise hypotension (PEH). We investigated through meta-analysis the after-effects of acute resistance exercise (RE) on blood pressure (BP) and autonomic activity in individuals with normal and elevated BP. Electronic databases were searched for trials including: adults; exclusive RE interventions; and BP and autonomic outcomes measured pre- and postintervention for at least 30 min. Analyses incorporated random-effects assumptions. Thirty trials yielded 62 interventions (N = 480). Subjects were young (33.6 ± 15.6 yr), with systolic BP (SBP)/diastolic BP (DBP) of 124.2 ± 8.9/71.5 ± 6.6 mm Hg. Overall, RE moderately reduced SBP (normal BP: ~1 to 4 mm Hg, p < 0.01; elevated BP: ~1 to 12 mm Hg, p < 0.01) and DBP (normal BP: ~1 to 4 mm Hg, p < 0.03; elevated BP: ~0.5 to 7 mm Hg, p < 0.01), which was in general parallel to sympathetic increase (normal BP: g = 0.49 to 0.51, p < 0.01; elevated BP: g = 0.41 to 0.63, p < 0.01) and parasympathetic decrease (normal BP: g = -0.52 to -0.53, p < 0.01; elevated BP: g = -0.46 to -0.71, p < 0.01). The meta-regression showed inverse associations between the effect sizes of BP vs. sympathetic (SBP: slope - 0.19 to -3.45, p < 0.01; DBP: slope - 0.30 to -1.60, p < 0.01), and direct associations vs. parasympathetic outcomes (SBP: slope 0.17 to 2.59, p < 0.01; DBP: slope 0.21 to 1.38, p < 0.01). In conclusion, changes in BP were concomitant to sympathetic increase and parasympathetic decrease, which questions the role of autonomic fluctuations as potential mechanisms of PEH after RE.

Effects of aerobic, resistance and concurrent exercise on pulse wave reflection and autonomic modulation in men with elevated blood pressure.

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/m2, 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.

Hemodynamics and cardiac autonomic modulation after an acute concurrent exercise circuit in older individuals with pre- to established hypertension.

OBJECTIVES: Few studies have investigated whether post-exercise hypotension (PEH) after concurrent exercise (CEX) is related to changes in cardiac output (Q) and systemic vascular resistance (SVR) in older individuals. We tested whether PEH after a single bout of CEX circuits performed in open-access facilities at the Third Age Academies (TAA) in Rio de Janeiro City (Brazil) would be concomitant with decreased Q and SVR in individuals aged ≥60 years with prehypertension. Moreover, we assessed autonomic modulation as a potential mechanism underlying PEH. METHODS: Fourteen individuals (age, 65.8±0.9 y; systolic/diastolic blood pressure [SBP/DBP], 132.4±12.1/72.8±10.8 mmHg; with half of the patients taking antihypertensive medications) had their blood pressure (BP), heart rate (HR), Q, SVR, HR variability (HRV), and spontaneous baroreflex sensitivity (BRS) recorded before and 50 min after CEX (40-min circuit, including seven stations of alternate aerobic/resistance exercises at 60-70% HR reserve) and non-exercise control (CONT) sessions. The study protocol was registered in a World Health Organization-accredited office (Trial registration RBR-7BWVPJ). RESULTS: SBP (Δ=-14.2±13.1 mmHg, p=0.0001), DBP (Δ=-5.2±8.2 mmHg, p= 0.04), Q (Δ=-2.2±1.5 L/min, p=0.0001), and BRS (Δ=-3.5±2.6 ms/mmHg; p=0.05) decreased after CEX as compared with the CONT session. By contrast, the HR increased (Δ=9.4±7.2 bpm, p<0.0001), and SVR remained stable throughout the postexercise period as compared with the CONT session (Δ=0.10±0.22 AU, p=0.14). We found no significant difference between the CEX and CONT with respect to the HRV indexes reflecting autonomic modulation. CONCLUSION: CEX induced PEH in the older individuals with prehypertension status. At least in the first 50 min, PEH occurred parallel to the decreased Q and increased HR, while SVR was not different. The changes in autonomic outflow appeared to be unrelated to the acute cardiac and hemodynamic responses.

Effects of cycling bouts performed with different intensities and amounts of energy expended on central pressure and pulse wave reflection in normotensive and hypertensive men.

OBJECTIVE: This study investigated pulse wave analysis in normotensive and hypertensive men after cycling bouts with different intensities and amounts of energy expended. METHODS: Twenty-four men were assigned into normotensive (n = 14; age: 40.7 ± 2.8 years; 24-h ambulatory SBP/DBP:121 ± 2/74 ± 1 mmHg) and hypertensive (n = 10; age: 39.2 ± 2.3 years; 24-h ambulatory SBP/DBP:139 ± 3/86 ± 2 mmHg) groups. Participants undertook a maximal cardiopulmonary exercise test, a nonexercise control session (CTL) and three cycling bouts [two prolonged bouts expending 300 kcal at 50% (i.e. P-MOD) and 70% (i.e. P-VIG) oxygen uptake reserve (VO2R) and one short bout expending 150 kcal at 50% VO2R (i.e. S-MOD)] performed in a randomized order. Central SBP (cSBP), pulse pressure (cPP), augmentation pressure, augmentation index (AIx), heart rate (HR) and AIx adjusted for HR (AIx@75) were determined 10 min before, and 30- and 70-min postintervention. RESULTS: Compared to CTL, only the P-VIG changed the cSBP [70-min (Δ -11.7 mmHg)], cPP [70-min (Δ:-7.4 mmHg)], augmentation pressure [30-min (Δ:-5.7 mmHg); 70-min (Δ:-7.3 mmHg)], AIx [30-min (Δ:-15.3 %); 70-min (Δ:-16.4 %)], AIx@75 [30-min (Δ:-12.8 %); 70-min (Δ:-13.9 %)] and HR [70-min (Δ: 9.9 bpm)] in the hypertensive group. However, all exercise bouts mitigated the increased cSBP responses post-CTL in the hypertensive group. CONCLUSION: The present study provides evidence that vigorous-intensity aerobic exercise reduces acute central pressure and pulse wave reflection in hypertensive men.

Influence of Different Treadmill Inclinations on V̇o2max and Ventilatory Thresholds During Maximal Ramp Protocols.

ABSTRACT: Silva, SC, Monteiro, WD, Cunha, FA, and Farinatti, P. Influence of different treadmill inclinations on V̇o2max and ventilatory thresholds during maximal ramp protocols. J Strength Cond Res 35(1): 233-239, 2021-Ramp protocols for cardiopulmonary exercise testing (CPET) lack precise recommendations, including optimal treadmill inclination. This study investigated the impact of treadmill grades applied in ramp CPETs on maximal oxygen uptake (V̇o2max), ventilatory thresholds (VT1/VT2), and V̇o2 vs. workload relationship. Twenty-one healthy men (age 33 ± 8 years; height 176.6 ± 5.8 cm; body mass 80.4 ± 8.7 kg; and V̇o2max 44.9 ± 5.7 ml·kg-1·min-1) and 12 women (age 29 ± 7 years; height 163.3 ± 6.7 cm; body mass 56.6 ± 6.3 kg; and V̇o2max 39.4 ± 4.9 ml·kg-1·min-1) underwent ramp CPETs with similar speed increments and different treadmill grades: CPET0%, CPET2%, CPET3.5%, and CPET5.5%. The V̇o2max was similar across protocols (42.8-43.2 ml·kg-1·min-1, p = 0.76), albeit duration of CPETs shortened when treadmill inclination increased (CPET0% 12.7 minutes; CPET2% 9.1 minutes; CPET3.5% 8.0 minutes; and CPET5.5% 6.6 minutes; p < 0.01). The %V̇o2max corresponding to VT1 was slightly lower in CPET0% (63.6%) and higher in CPET5.5% (75.8%) vs. CPET2% (67.8%) and CPET3.5% (69.5%; p < 0.05), whereas VT2 was not affected by treadmill inclination (95.1-95.8% V̇o2max; p > 0.05). V̇o2max and ventilatory thresholds were similar in CPETs performed with different treadmill inclinations and similar initial/final speeds. However, linear regressions between workload and V̇o2 were closer to the identity line in CPETs performed with smaller (CPET0% and CPET2%) than with greater (CPET3.5% and CPET5.5%) inclinations. These data suggest that in healthy young adults, ramp CPETs performed with inclinations of 0-2% degree should be preferred over protocols with greater inclinations.

Hemodynamics and cardiac autonomic modulation after an acute concurrent exercise circuit in older individuals with pre- to established hypertension

OBJECTIVES: Few studies have investigated whether post-exercise hypotension (PEH) after concurrent exercise (CEX) is related to changes in cardiac output (Q) and systemic vascular resistance (SVR) in older individuals. We tested whether PEH after a single bout of CEX circuits performed in open-access facilities at the Third Age Academies (TAA) in Rio de Janeiro City (Brazil) would be concomitant with decreased Q and SVR in individuals aged ≥60 years with prehypertension. Moreover, we assessed autonomic modulation as a potential mechanism underlying PEH. METHODS: Fourteen individuals (age, 65.8±0.9 y; systolic/diastolic blood pressure [SBP/DBP], 132.4±12.1/72.8±10.8 mmHg; with half of the patients taking antihypertensive medications) had their blood pressure (BP), heart rate (HR), Q, SVR, HR variability (HRV), and spontaneous baroreflex sensitivity (BRS) recorded before and 50 min after CEX (40-min circuit, including seven stations of alternate aerobic/resistance exercises at 60-70% HR reserve) and non-exercise control (CONT) sessions. The study protocol was registered in a World Health Organization-accredited office (Trial registration RBR-7BWVPJ). RESULTS: SBP (Δ=−14.2±13.1 mmHg, p=0.0001), DBP (Δ=−5.2±8.2 mmHg, p= 0.04), Q (Δ=−2.2±1.5 L/min, p=0.0001), and BRS (Δ=−3.5±2.6 ms/mmHg; p=0.05) decreased after CEX as compared with the CONT session. By contrast, the HR increased (Δ=9.4±7.2 bpm, p<0.0001), and SVR remained stable throughout the postexercise period as compared with the CONT session (Δ=0.10±0.22 AU, p=0.14). We found no significant difference between the CEX and CONT with respect to the HRV indexes reflecting autonomic modulation. CONCLUSION: CEX induced PEH in the older individuals with prehypertension status. At least in the first 50 min, PEH occurred parallel to the decreased Q and increased HR, while SVR was not different. The changes in autonomic outflow appeared to be unrelated to the acute cardiac and hemodynamic responses.

Effects of judo training upon body composition, autonomic function, and cardiorespiratory fitness in overweight or obese children aged 8- to 13 years.

Physical training is recommended for obese paediatric populations. We investigated the effects of recreational judo training (JT) upon body composition and distribution, cardiorespiratory fitness, and heart rate variability (HRV) in overweight or obese children. A controlled trial (RBR-9d94td) was conducted with 35 children (8-13 years) assigned into groups according to their body mass index (BMI): eutrophic (EU; n = 15; z-BMI ≤ +l and ≥ -2) and overweight or obese (OB; n = 20; z-BMI > +1 and ≤ +3). The 12-week JT included 60-min sessions performed 2 times/week at 65-75% maximal heart rate (HR). BMI, waist circumference, blood pressure, HRV, peak oxygen uptake (VO2peak), gas exchange threshold (GET), and body fractioning were assessed. Significant reductions in OB (P < 0.05) occurred for whole body and trunk fat (~3%), trunk/limb fat-ratio (~4%), resting HR (~3%), and sympathovagal balance (log LF:HF, ~85%). Increases (P < 0.05) occurred in lean mass (~8%), parasympathetic modulation (log HF, ~4%), VO2peak (~5-10%), and VO2 (~15%), speed (~10%) and slope (~13%) at GET. Markers of cardiorespiratory fitness (relative VO2, slope and speed at GET) in OB approached EU after JT. In conclusion, a relatively short JT intervention to improved body composition, autonomic modulation, and physical fitness in obese children.

Acute Effect of a Single Session of Pilates on Blood Pressure and Cardiac Autonomic Control in Middle-Aged Adults With Hypertension.

Rocha, J, Cunha, FA, Cordeiro, R, Monteiro, W, Pescatello, LS, and Farinatti, P. Acute effect of a single session of Pilates on blood pressure and cardiac autonomic control in middle-aged adults with hypertension. J Strength Cond Res 34(1): 114-123, 2020-We investigated the blood pressure (BP) and heart rate variability (HRV) responses to a single session of Pilates among adults with hypertension. Thirteen participants (7 women), aged 44-66 years, underwent Pilates and nonexercise control sessions separated by 48-72 hours in a randomized counterbalanced order. Blood pressure and HRV indices were simultaneously assessed 10 minutes before and 60 minutes after all sessions in the supine position: root mean square of successive differences (rMSSD), percentage of successive normal sinus RR intervals >50 ms (pNN50), SD of all normal sinus RR intervals over 24 hours (SDNN), and low-frequency (LF) and high-frequency (HF) bands. After an acute session of Pilates, the mean values for area under the curve for systolic BP (p = 0.004, corresponding to -7.4 ± 8.2 mm Hg) and mean arterial pressure (p = 0.023, corresponding to -5.3 ± 5.4 mm Hg) were significantly lower compared to the control session. No significant difference was detected for diastolic BP (-4.2 ± 4.7 mm Hg, p = 0.106). Concomitant to BP reduction, significant lowering of parasympathetic HRV indices occurred: RR intervals (-64.1 ± 69.9 ms·min, p = 0.043), rMSSD (-8.3 ± 15.4 ms·min, p = 0.013), pNN50 (-3.6 ± 13%·min, p = 0.028), and total power (-3,089.4 ± 5,938 m·min, p = 0.037). No difference was found for sympathetic markers: SDNN (-17.7 ± 34.6 ms·min, p = 0.100), LF (-5.2 ± 21,6 n.u.·min, p = 0.417), and LF:HF ratio (-0.3 ± 5.2 ratio·min, p = 0.422). In conclusion, a single session of Pilates reduced BP by ∼5-8 mm Hg in adults with hypertension during the first 60 minutes of post-exercise recovery. Acute BP reduction was concomitant to lowered cardiac parasympathetic activity. Our findings are promising for the use of Pilates as an alternative exercise modality to lower BP.

Four-second dynamic exercise testing (T4S) for the assessment of cardiac vagal modulation in obese adolescents.

BACKGROUND: Reduced vagal activity is often present in obese adolescents. Simple and practical strategies for the assessment of isolate parasympathetic outflow in this population are therefore useful. OBJECTIVES: To compare the methods derived from heart rate variability (HRV) analysis at rest and 4 s exercise testing (T4S) for the assessment of cardiac parasympathetic modulation in adolescents classified as obese (OB) or with normal weight (NW). Additionally, associations between total and trunk fat versus autonomic modulation determined by the two methods were calculated. APPROACH: A cross-sectional study was conducted with 50 adolescents (26 OB and 24 NW, 14.7 ± 1.5 years), comparing autonomic indices provided by HRV and T4S. Body fractioning was determined employing dual-energy x-ray absorptiometry (DXA). MAIN RESULTS: The cardiac vagal index (CVI) obtained from T4S and standard time- and frequency-domain HRV measures were lower in OB versus NW (P ⩽ 0.05). Correlations between CVI and HRV indices of cardiac vagal modulation were as follows: CVI versus RMSSD (r = 0.44; P = 0.003); CVI versus pNN50 (r = 0.32; P = 0.04); CVI versus HF (r = 0.35; P = 0.02). Associations between body fat, android/gynoid ratio, and percent trunk fat versus CVI were of similar magnitude and direction than versus HRV indices. SIGNIFICANCE: The T4S proved to be adequate to detect cardiac parasympathetic impairment in obese adolescents. Moreover, vagal modulation assessed by HRV and T4S inversely correlated with visceral adipose tissue. These findings along with the simplicity and safety of the T4S should encourage its use in the assessment of cardiac parasympathetic modulation in obese pediatric populations.