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.

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.

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.

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.

Acute Effect of Aerobic and Strength Exercise on Heart Rate Variability and Baroreflex Sensitivity in Men With Autonomic Dysfunction.

de 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 = 10: 33.8 ± 3.0 years; 23.7 ± 1.5 kg·m) and CADysf (n = 10: 36.2 ± 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 [Cohen's d]: >1.4) and BRS at rest were significantly lower in CADysf than those in controls (p < 0.01; effect size [Cohen's 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 [Cohen's d]: ≥1.31) and SE (p ≤ 0.05; effect size [Cohen's d]: ≥0.79) vs. CTL, but changes were larger after AE than SE (p ≤ 0.05; effect size [Cohen's 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.

Cardiorespiratory responses and myocardial function within incremental exercise in healthy unmedicated older vs. young men and women.

BACKGROUND: Age-related differences concerning cardiorespiratory responses and myocardial function during exercise have not been extensively investigated in healthy populations. AIMS: To compare cardiorespiratory performance and myocardial function during maximal exercise in healthy/unmedicated men (older, n = 24, 63-75 years; young, n = 22, 19-25 years) and women (older, n = 18, age = 63-74 years; young, n = 23, 19-25 years). METHODS: Oxygen uptake (VO2), ventilation minute (V E), heart rate (HR), stroke volume (SV), cardiac output (Q), O2 pulse (O2p), preejection period (PEP), and left ventricular ejection time (LVET) were assessed during cycle incremental exercise. RESULTS: HR and SV remained equivalent between age groups until 75 and 50% peak workload, respectively. Q increased by 2.5 and 4.5 times in older and young groups, respectively. However, Q/VO2 ratio was always similar across age and sex groups (∼0.50). The energetic efficiency ratio (W/VO2) was also alike in older and young men, but slightly lower in women. At maximal exercise, cardiorespiratory responses were lower in older than young men and women: VO2 (-40 to 50%), V E (-35 to 37%), HR (-23%), SV (-26 to 29%), Q (-43 to 45%), and O2p (-15 to 20%). Cardiac and SV indices were lower in older than young groups by approximately 42 and 25%, respectively. LVET was longer in the older individuals, while PEP was similar across age groups. Hence, PEP/LVET was lowered among older vs. young men and women. CONCLUSION: Submaximal work capacity was preserved in healthy and unmedicated older individuals. Age-related lessening of maximal performance in both sexes was due to poor chronotropic and, particularly, inotropic properties of the heart.

Influence of Acute Concurrent Exercise Performed in Public Fitness Facilities on Ambulatory Blood Pressure Among Older Adults in Rio de Janeiro City.

Cordeiro, R, Monteiro, W, Cunha, F, Pescatello, LS, and Farinatti, P. Influence of acute concurrent exercise performed in public fitness facilities on ambulatory blood pressure among older adults in Rio de Janeiro city. J Strength Cond Res 32(10): 2962-2970, 2018-The project "Third-Age Academies'" (TAAs) is a public policy providing supervised physical activities to over 40,000 seniors at open-access facilities (squares etc.) in Rio de Janeiro, Brazil. We investigated whether TAA concurrent exercise circuit induced postexercise hypotension (PEH) in individuals older than 60 years. Blood pressure (BP) was measured by 24-hour ambulatory BP monitoring (ABPM) after counterbalanced CEX and nonexercise (CONT) sessions (n = 16; 66.8 ± 1.4 years; systolic/diastolic BP (SBP/DBP): 132.5 ± 4.3/78.0 ± 2.8 mm Hg). For statistical analyses purposes, groups were divided as exhibiting normal SBP (≤120 mm Hg) or high SBP (>120 mm Hg), based on 24-hour ABPM after CONT. The CEX included 2 aerobic and 9 resistance exercises performed alternately in circuit order (40 minutes at 60-70% heart rate reserve using body mass or fixed loads). 24-hour ambulatory BP monitoring lowered in individuals with high BP (n = 11; medicated = 5) (SBP: -6.5 ± 1.9 mm Hg; mean arterial pressure [MAP]: -4.3 ± 1.5 mm Hg; p < 0.015), particularly within the first 5-6 hours after exercise (SBP: -13.5 ± 2.6 mm Hg; DBP: -9.4 ± 2.2 mm Hg; and MAP: -11.4 ± 1.6 mm Hg, p < 0.05). Significant BP lowering was not detected among participants with normal BP (n = 5; medicated = 4). In conclusion, CEX provoked PEH in older adults with prehypertension to established hypertension. Because of the potential of TAAs to reach large numbers of older adults, our findings are encouraging and should be confirmed in subsequent studies.

Optimizing a Treadmill Ramp Protocol to Evaluate Aerobic Capacity of Hemiparetic Poststroke Patients.

Bernardes, WL, Montenegro, RA, Monteiro, WD, de Almeida Freire, R, Massaferri, R, and Farinatti, P. Optimizing a treadmill ramp protocol to evaluate aerobic capacity of hemiparetic poststroke patients. J Strength Cond Res 32(3): 876-884, 2018-A correct assessment of cardiopulmonary capacity is important for aerobic training within motor rehabilitation of poststroke hemiparetic patients (PSHPs). However, specific cardiopulmonary exercise testing (CPET) for these patients are scarce. We proposed adaptations in a protocol originally developed for PSHPs by Ovando et al. (CPET1). We hypothesized that our adapted protocol (CPET2) would improve the original test, by preventing early fatigue and increasing patients' peak performance. Eleven PSHPs (52 ± 14 years, 10 men) performed both protocols. CPET2 integrated changes in final speed (100-120% vs. 140% maximal speed in 10-m walking test), treadmill inclination (final inclination of 5 vs. 10%), and estimated test duration (10 vs. 8 minutes) to smooth the rate of workload increment of CPET1. Peak oxygen uptake (V[Combining Dot Above]O2peak) (20.3 ± 6.1 vs. 18.6 ± 5.0 ml·kg·min; p = 0.04), V[Combining Dot Above]O2 at gas exchange transition (V[Combining Dot Above]O2-GET) (11.5 ± 2.9 vs. 9.8 ± 2.0 ml·kg·min; p = 0.04), and time to exhaustion (10 ± 3 vs. 6 ± 2 minutes; p < 0.001) were higher in CPET2 than in CPET1. Slopes and intercepts of regressions describing relationships between V[Combining Dot Above]O2 vs. workload, heart rate vs. workload, and V[Combining Dot Above]O2 vs. heart rate were similar between CPETs. However, standard errors of estimates obtained for regressions between heart rate vs. workload (3.0 ± 1.3 vs. 3.8 ± 1.0 b·min; p = 0.004) and V[Combining Dot Above]O2 vs. heart rate (6.0 ± 2.1 vs. 4.8 ± 2.4 ml·kg·min; p = 0.05) were lower in CPET2 than in CPET1. In conclusion, the present adaptations in Ovando's CPET protocol increased exercise tolerance of PSHPs, eliciting higher V[Combining Dot Above]O2peak and V[Combining Dot Above]O2-GET, preventing earlier fatigue, and providing better physiological relationships along submaximal workloads.

Continuous and Accumulated Bouts of Cycling Matched by Intensity and Energy Expenditure Elicit Similar Acute Blood Pressure Reductions in Prehypertensive Men.

Fonseca, 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 (SBP: [INCREMENT] - 3.4 mm Hg, p < 0.001; MAP: [INCREMENT] - 2.5 mm Hg, p = 0.001), INTER1 (SBP: [INCREMENT] - 2.2 mm Hg, p = 0.045), and INTER2 (SBP: [INCREMENT] - 4.4 mm Hg, p < 0.001; DBP: [INCREMENT] - 2.7 mm Hg, p = 0.045; MAP: [INCREMENT] - 3.3 mm Hg, p = 0.001). The PEH was similar in CONTIN and INTER2, whereas INTER2 elicited greater PEH than INTER1 (SBP and MAP: [INCREMENT] - 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.

Locomotion Mode Affects the Physiological Strain during Exercise at Walk-Run Transition Speed inElderly Men.

This study investigated cardiorespiratory responses and rating of perceived exertion (RPE) during prolonged walking and running exercise performed at the walk-run transition speed (WRTS) in untrained healthy elderly men. 20 volunteers (mean±SE, age: 68.4±1.2 yrs; height: 170.0±0.02 cm; body mass: 74.7±2.3 kg) performed the following bouts of exercise: a) maximal cardiopulmonary exercise test (CPET); b) specific protocol to detect WRTS; and c) two 30-min walking and running bouts at WRTS. Expired gases were collected during exercise bouts via the Ultima CardiO2 metabolic analyzer. Compared to walking, running at the WRTS resulted in higher oxygen uptake (>0.27 L·min-1), pulmonary ventilation (>7.7 L·min-1), carbon dioxide output (>0.23 L·min-1), heart rate (>15 beats·min-1), oxygen pulse (>0.88 15 mL·beats-1), energy expenditure (>27 kcal) and cost of oxygen transport (>43 mL·kg-1·km-1·bout-1). The increase of overall and local RPEs with exercise duration was similar across locomotion modes (P<0.001). In all participants, %HRR and %VO2R throughout walking and running bouts were around or above the gas exchange threshold. In conclusion, elderly men exhibited higher cardiorespiratory responses during 30-min bouts of running than walking at WRTS. Nevertheless, walking corresponded to relative metabolic intensities compatible with preservation or improvement of cardiorespiratory fitness and should be preferable over running at WRTS in the untrained elderly characterized by poor fitness and reduced exercise tolerance.

Cardiovascular Responses to Resistance Exercise Performed with Large and Small Muscle Mass.

Prior research about the effects of the amount of exercised muscle mass upon cardiovascular responses (CVR) has neglected a potential bias related to total exercise and concentric/eccentric duration. Autonomic responses and perceived exertion (RPE) were compared in resistance exercises performed with larger and smaller muscle mass and matched for total exercise and concentric/eccentric duration. Twelve men performed 4 sets of 12 repetitions of unilateral (UNI) and bilateral (BIL) knee extensions at 70% of 12RM. Increases in CVR were always greater at the last set of BIL over UNI, as were SBP (35% vs. 23%), DBP (36% vs. 23%), HR (40% vs. 26%), RRP (90% vs 53%) and CO (55% vs 39%). No difference between protocols was found for autonomic modulation before and after exercise, but BIL induced significantly greater changes than UNI from baseline for R-R intervals (-13% vs. -7%), SDNN (-38% vs. -17%) and rMSSD (-41% vs. -21%). The rate of perceived exertion in the last set was higher in BIL than UNI (7.6±0.5 vs. 6.6±1.4 OMNI-RES; P<0.05) and did not correlate with any CVR. Thus, CVR were greater in resistance exercise performed with larger than smaller muscle mass. This information is relevant for patients with high cardiovascular risk.

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.

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.

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.

How long does it take to achieve steady state for an accurate assessment of resting VO2 in healthy men?

The time necessary to obtain a steady state for an accurate and reliable assessment of resting [Formula: see text] remains unclear and was the purpose of this study. Thirty healthy men, aged 17-28 years, visited the laboratory twice for the assessment of resting [Formula: see text], which was assessed as follows: (a) 24 h abstention from physical exercise, alcohol, soft drinks and caffeine, (b) fasting for at least 8 h, (c) an acclimation period of 10 min, and (d) 60 min assessment in a supine position. Resting [Formula: see text] significantly changed during the 60 min (F = 37.4, P < 0.001), exhibiting a monoexponential decrease before reaching an asymptote. Post hoc pairwise comparisons showed that significant differences existed between consecutive means until the 30 min time point, after which there were no significant differences. The [Formula: see text] response across trials exhibited high test-retest reliability, with within-subject coefficients of variations at each time point ranging from 2.8 to 7.0 % and intraclass correlation coefficients ranging from 0.90 to 0.99. The reliability was higher from the 25 min time point onwards. Based on these findings, the following recommendations are made to promote accurate assessment of resting [Formula: see text]: (a) initiate the resting [Formula: see text] measurement with 10 min of acclimation to the assessment apparatus, (b) determine resting [Formula: see text] for a minimum of 30 min, until an apparent [Formula: see text] steady state has been achieved; and (c) determine resting [Formula: see text] for a further 5 min, with the average of this last 5 min of data being regarding as the resting [Formula: see text].

Influence of exercise order on the number of repetitions, oxygen uptake, and rate of perceived exertion during strength training in younger and older women.

The study investigated the effect of resistance exercise order on the number of repetitions, oxygen uptake (VO(2max)) and rate perceived exertion (RPE) in younger (YG: N = 10; 22 ± 2 years; VO(2peak) 42.2 ± 2.9 ml·kg(-1)·min(-1)) and older (EG: N = 8; 69 ± 7 years; VO(2peak)22.7 ± 2.5 ml·kg(-1)·min(-1)) women. The subjects performed 3 sets of each exercise until fatigue using 10 repetition maximum in 2 sequences of opposite order: (a) sequence A (SEQA): bench press (BP), machine shoulder press (SP), pulley triceps extension (TE); (b) sequence B (SEQB): TE-SP-BP. The VO(2) was assessed during the exercises, rest intervals, and 20 minutes after sequences (postexercise oxygen consumption [EPOC]). The number of repetitions decreased in both groups (p < 0.05) throughout sets. No difference (p > 0.22) was found between sequences for total VO(2) (exercise sequences + EPOC) in YG (SEQA = 25.41 ± 6.51 L vs. SEQB = 24.81 ± 4.08 L) and EG (SEQA = 26.45 ± 5.24 L vs. SEQB = 26.91 ± 4.62 L). In both groups, the VO(2) within the sequences was higher during BP when it was placed at the end of SEQB, the same occurring with TE in SEQA (p < 0.05). The VO(2) within sequences and RPE were higher in SEQB compared with SEQA (p < 0.05) in EG but not in YG. In conclusion, the exercise order did not affect total VO(2). The VO(2) within a given sequence was always lower when an exercise was performed first as compared with last regardless of the exercise order. Accumulated fatigue reflected by the VO(2) within sequences and RPE was influenced by the exercise order only in EG, suggesting that to prevent early fatigue, resistance training sessions in this group should preferably progress from large toward small-muscle group exercises.

Acute effect of proprioceptive neuromuscular facilitation stretching on the number of repetitions performed during a multiple set resistance exercise protocol.

It has been proposed that fatigue during strength exercise is negatively influenced by prior proprioceptive neuromuscular facilitation (PNF) stretching. However, it is possible that the effects of PNF on muscle endurance are affected by stretching duration. This study investigated the influence of PNF on the number of repetitions of the leg curl exercise performed with multiple sets and submaximal load. Nineteen men (age 25 ± 1 years, weight 75.8 ± 4.2 kg, height 178.1 ± 3.8 cm, 10-repetition maximum [RM] 78.3 ± 6.9 kg) performed 4 sets of leg curl with 10RM load with and without previous PNF (3 sets of hip flexion either with knees extended or flexed, duration ~2.5 minutes). The total number of repetitions decreased along sets in both situations (38.6% in control and 41.0% in PNF sessions, p < 0.001). However, no difference between control and PNF was detected for the number of repetitions in each set (first set, p = 0.330; second set, p = 0.072; third set, p = 0.061; fourth set, p = 0.150). In conclusion, the number of repetitions performed in multiple sets of the leg curl was not decreased by prior PNF stretching. Therefore, it appears that a moderate level of PNF could be used before resistance exercise with a minimal negative effect.

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.