Effects of School-Based High-Intensity Interval Training on Hemodynamic Parameters and Heart Rate Variability: A Randomized Controlled Trial.

ABSTRACT: Ketelhut, S, Ketelhut, K, Ketelhut, SR, and Ketelhut, RG. Effects of school-based high-intensity interval training on hemodynamic parameters and heart rate variability: A randomized controlled trial. J Strength Cond Res 38(6): 1033-1040, 2024-The purpose of this study was to assess the effects of a child-specific school-based high-intensity interval training (HIIT) implemented into physical education (PE) classes on various hemodynamic parameters and heart rate variability indices. Forty-six students (age 11 ± 1 year) were randomized into an intervention (INT n = 22) and a control group (CON n = 24). During a 12-week period, the INT and CON groups participated in regular PE twice weekly (45-90 minutes). The INT group received HIIT during the first 20 minutes of the 2 PE classes. Systolic and diastolic blood pressure, total peripheral resistance, aortic pulse wave velocity (aPWV), heart rate, SD of normal to normal heartbeat intervals, the root mean square of successive differences between normal heartbeats (RMSSD), the proportion of differences between adjacent normal to normal heartbeat intervals of more than 50 ms, low-frequency power, high-frequency power, and the LF/HF ratio were assessed before and after the experimental period. A p value ≤0.05 was considered statistically significant. Forty students (20 INT; 20 CON) were included in the analysis. A significant time × group interaction was detected for aPWV ( p = 0.05, η2 = 0.099), RMSSD ( p = 0.010, η2 = 0.161), low-frequency power ( p = 0.009, η2 = 0.165), high-frequency power ( p < 0.001, η2 = 0.272), and the LF/HF ratio ( p < 0.001, η2 = 0.354). The INT group revealed significant improvements for the respective parameters. School-based HIIT can induce improvements in cardiovascular parameters. These results highlight the potential of embedding HIIT within the school setting, offering a time-efficient exercise intervention.

Interval Training in Sports Medicine: Current Thoughts on an Old Idea.

In light of the global physical inactivity pandemic, the increasing prevalence of non-committable diseases, and mounting healthcare costs, effective and feasible prevention and treatment approaches are urgently needed [...].

Influence of Initial Severity of Depression on the Effectiveness of a Multimodal Therapy on Depressive Score, Heart Rate Variability, and Hemodynamic Parameters.

Depression is a major cause of disability among populations worldwide. Apart from primary symptoms, depressed patients often have a higher cardiovascular risk profile. Multimodal therapy concepts, including exercise, have emerged as promising approaches that not only improve depressive symptoms but also have a positive impact on cardiovascular risk profile. However, controversies have arisen concerning the influence of baseline severity on the effects of therapy concepts for this demographic. This study assessed whether pretreatment severity moderates psychological and physiological treatment outcomes of a multimodal therapy. A total of 16 patients diagnosed with mild depression (MD) and 14 patients diagnosed with severe depression (SD) took part in a 3-month outpatient multimodal treatment therapy. Before and after the treatment, depression score (Beck Depression Inventory (BDI)), peripheral systolic (pSBP) and diastolic (pDBP) blood pressure, central systolic (cSBP) and diastolic (cDBP) blood pressure, pulse wave velocity (PWV), heart rate (HR), and parasympathetic parameters of heart rate variability (RMSSD) were assessed. Significant time effects were detected for BDI (−20.0 ± 11.6, p > 0.001, η2 = 0.871), pSBP (−4.7 ± 6.8 mmHg, p < 0.001, η2 = 0.322), pDBP (−3.5 ± 6.9 mmHg, p = 0.01, η2 = 0.209), cSBP (−4.8 ± 6.5 mmHg, p < 0.001, η2 = 0.355), cDBP (−3.6 ± 6.8 mmHg, p = 0.008, η2 = 0.226), PWV (−0.13 ± 0.23 m/s, p = 0.008, η2 = 0.229), HR (4.3 ± 8.8 min−1, p = 0.015, η2 = 0.193), RMSSD (−12.2 ± 23.9 ms, p = 0.017, η2 = 0.251), and and SDNN (10.5 ± 17.8 ms, p = 0.005, η2 = 0.330). Significant time × group interaction could be revealed for BDI (p < 0.001, η2 = 0.543), with patients suffering from SD showing stronger reductions. Pretreatment severity of depression has an impact on the effectiveness of a multimodal therapy regarding psychological but not physiological outcomes.

Gaming Instead of Training? Exergaming Induces High-Intensity Exercise Stimulus and Reduces Cardiovascular Reactivity to Cold Pressor Test.

INTRODUCTION: The present study assessed if an exercise session in an innovative exergame can modulate hemodynamic reactivity to a cold pressor test (CPT) to a similar extent as a typical moderate endurance training (ET). Furthermore, cardiorespiratory, and affective responses of an exergame session and an ET were compared. METHODS: Twenty-seven healthy participants aged 25 ± 4 years (48% female; BMI 23.0 ± 2.1 kg/m2) participated in this cross-sectional study. All participants completed both an ET on a treadmill and training in the ExerCube (ECT). HR and oxygen consumption were recorded during both training sessions. Before and after both exercise sessions, the hemodynamic reactivity to a CPT was determined. RESULTS: During ECT, HR, oxygen consumption, energy expenditure, and the metabolic equivalent of the task were significantly higher than those obtained during ET (p < 0.001). With regard to the CPT, the participants showed significantly lower responses in peripheral systolic (p = 0.004) and diastolic blood pressure (p = 0.009) as well as central systolic (p = 0.002) and diastolic BP (P = 0.01) after ECT compared to ET. The same was true for pulse wave velocity (p = 0.039). CONCLUSION: The ECT induced a significantly higher exercise stimulus compared to the ET. At the same time, it attenuated hemodynamic stress reactivity. The ECT presents a relevant training stimulus that modulates cardiovascular reactivity to stress, which has been proven as a predictor for the development of hypertension. TRIAL REGISTRATION: ISRCTN registry, ISRCTN43067716, 14 April 2020, Trial number: 38154.

A Game-Based Approach to Lower Blood Pressure? Comparing Acute Hemodynamic Responses to Endurance Exercise and Exergaming: A Randomized Crossover Trial.

The present randomized crossover study aimed to determine whether an exergaming session in an innovative, functional fitness game could be an effective exercise approach that elicits favorable blood pressure (BP) responses, such as a typical moderate endurance exercise (ET). Therefore, acute hemodynamic responses after a training session in the ExerCube and an ET on a treadmill were assessed and compared. Twenty-eight healthy recreational active participants (13 women; aged 24.8 ± 3.9 years) completed an exergaming session (EX) and an ET in a randomized and counterbalanced order. Before and throughout the 45 min after the training, the peripheral and central BP were measured. After the ET, there was a moderate decrease in both peripheral systolic (-1.8 mmHg; p = 0.14) and diastolic (-0.8 mmHg; p = 0.003), as well as central diastolic (-1.5 mmHg; p = 0.006) pressure compared to the resting value before the exercise. After the EX, there was a significant decrease in peripheral systolic (-6.3 mmHg; p < 0.001) and diastolic (-4.8 mmHg; p < 0.001), as well as central systolic (-5.8 mmHg; p < 0.001) and diastolic (-5.3 mmHg; p < 0.001) pressure compared to baseline. The interaction effects showed significant differences in peripheral and central systolic BP as well as in peripheral diastolic BP (p = 0.05). The EX seems to be an effective training approach that triggers relevant peripheral and central BP-responses, which are more pronounced than after a typical ET. Therefore, the ExerCube can be a time-efficient training tool to improve cardiovascular health.

Acute Effects of Heart Rate-Controlled Exergaming on Vascular Function in Young Adults.

Objective: Acute and regular moderate-intensity endurance exercise (MIEE) is known to positively affect vascular function. The present study assessed if an exercise session in an innovative exergame called the ExerCube can induce similar vascular reactions as an MIEE session. Materials and Methods: Twenty-eight healthy recreationally active participants (13 females and 15 males; aged 24.8 ± 3.9 years; with body mass index 23.2 ± 2.3 kg/m2) completed an exergaming session (EGS) in the ExerCube (25 minutes) and an MIEE session on a treadmill (35 minutes, 65%-70% of maximal heart rate [HR]) in a randomized order. Both before and throughout the 45 minutes after the training sessions, pulse wave velocity (PWV), total peripheral resistance (TPR), stroke volume (SV), and HR were recorded. The study was approved by the Research Ethics Board of the Martin-Luther-Universität Halle-Wittenberg (Medical Faculty of the Martin-Luther-Universität 2019-177). Results: There were different hemodynamic responses to both types of exercises. PWV was significantly decreased 45 minutes after the EGS (P < 0.001). No significant changes were detected after MIEE (P = 0.109). TPR was significantly lower after both exercise sessions (P < 0.01). Only the EGS resulted in a significant decrease in SV 15 minutes after exercise (P < 0.001). The HR was significantly (P < 0.05) higher after both exercise sessions. After the EGS, the increase in HR was still significantly higher (P = 0.011) 45 minutes after the session. The interaction effects revealed significant differences in PWV (15 minutes, P = 0.035; 30 minutes, P = 0.004; and 45 minutes, P < 0.001), favoring the EGS. Conclusion: The EGS seems to induce a relevant exercise stimulus that can modulate vascular function. Therefore, this exergame may present an effective tool for prevention of cardiovascular diseases.

Adaptive High-Intensity Exergaming: The More Enjoyable Alternative to Conventional Training Approaches Despite Working Harder.

Objective: The purpose of this study was to assess psychological and physiological responses to an exergaming session in the ExerCube (EX) and compare them with the responses of a moderate endurance run (ER). Materials and Methods: Twenty-eight healthy adults (13 women) aged 24.8 ± 3.8 years took part in this study. The first test day, participants performed a graded exercise test on a treadmill to determine maximal heart rate (HR) and lactate levels. The following test days 2 and 3, the participants completed an EX session and an ER on a treadmill in a randomized counterbalanced order. HR, rate of perceived exertion (RPE), and lactate levels were assessed during both sessions. After the sessions, the participants completed the "Physical Activity Enjoyment Scale" and the "Flow Short Scale." Results: The analysis of variance revealed that enjoyment (P = 0.036), flow (P = 0.042), RPE (P = 0.005), as well as mean and peak HR (P < 0.001) during the EX session were significantly higher compared with the ER. Gender did not affect the differences between the two conditions for mean HR (P = 0.61), maximal HR (P = 0.122), RPE (P = 0.862), flow (P = 0.376) nor enjoyment (P = 0.867). During the EX session, the lactate levels of all participants exceeded the individual lactate threshold (LT). During the ER, lactate values remained below the LT. Conclusion: The ExerCube presents both a physiological relevant exercise stimulus and a joyful gaming experience. Despite the higher exercise intensity achieved during the EX session, enjoyment was significantly higher compared with the ER. Therefore, the EX can be a promising and appealing tool to facilitate physical activity. Trial registration: ISRCTN registry, ISRCTN43067716, April 14, 2020. Trial number: 38154.

Effects of Moderate- versus Mixed-Intensity Training on VO2peak in Young Well-Trained Rowers.

The effects of moderate-intensity continuous training (MICT) and a combination of MICT and high-intensity interval training (HIIT) on rowing performance and VO2peak were investigated in young athletes. Seventeen well-trained rowers (aged 15 ± 1.3 years) were randomly allocated to an intervention (IG) (n = 10) and control group (CG) (n = 7). During 8 weeks, both groups took part in the regular rowing training (3×/week MICT, 70-90 min, 65-70% of HRpeak + 2×/week resistance training). The IG completed an additional high-intensity interval training twice weekly (2 × 4 × 2 min at ≈95% of HRpeak, 60 s rest). Instead of the HIIT, the CG completed two more MICT sessions (70-90 min, 65-70% of HRpeak). Before and after the intervention, a 2000 m time trial and an exercise test were performed. The IG showed a significant improvement (p = 0.001) regarding the absolute rowing time in the graded exercise test. Furthermore, the intervention group showed a significant increase in relative VO2peak (p = 0.023), a significant increase in absolute VO2peak (p = 0.036), and a significant improvement in the 2000 m time trail (p = 0.003). No significant changes could be detected in the CG. The interaction effects were not significant. A mixed-intensity training, including HIIT, was beneficial on rowing performance and VO2peak in highly trained athletes.

Hemodynamics in young athletes following high-intensity interval or moderate-intensity continuous training.

BACKGROUND: The present study aimed to investigate the effects of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) on blood pressure (BP) and parameters of arterial stiffness in young athletes. METHODS: Seventeen rowers (aged 15±1.3 years) were randomized into an intervention group (IG, N.=10) and the control group (CG, N.=7). During an 8-week intervention period, the IG completed a HIIT on the rowing ergometer twice-weekly (2×4×2 min at ≈95% of maximum heart rate [HRmax], 60 s rest) in addition to the regular rowing training (3×/week MICT 70-90 min, ≈70% HRmax). The CG completed the regular normal rowing training and, instead of the HIIT units, two additional MICT units (70-90 min, ≈70% HRmax). Before and after the intervention period, hemodynamic parameters were recorded non-invasively in both groups. RESULTS: After the intervention period, there was a significant decrease in peripheral systolic (P=0.01) and diastolic (P=0.05) BP, as well as in central systolic (P=0.05) and diastolic BP (P=0.03) in the IG. Furthermore, pulse wave velocity (PWV) (P=0.05) was significantly reduced. Analysis of intervention effects revealed significant between-group differences in central diastolic BP (P=0.05), in augmentation pressure (P=0.02), and in augmentation index (P=0.006) favoring IG. The CG showed no significant changes in the respected parameters throughout the intervention. CONCLUSIONS: Already in adolescent athletes, a HIIT intervention has beneficial effects on peripheral and central BP as well as on PWV, augmentation pressure, and augmentation index.

Type of Exercise Training and Training Methods.

There is general agreement that exercise training leads to functional, morphological, and metabolic adaptations of different biological systems, thereby increasing overall physical performance and promoting good health. Thus, an active lifestyle is propagated in all age groups. However, not every exercise routine or workout is suitable for everyone. Inappropriate training can also pose risks, and too low or too high training intensity or volume often does not lead to the expected success. To ensure significant benefits, specific principles and strategies need to be considered and accustomed to the individual.This chapter summarizes the key exercise variables and training principles to consider when developing a training program to improve or maintain performance and health. In addition, the various steps for creating an individual training program are described, and an overview of the different training methods and training strategies is given.

Left Ventricular Hypertrophy in Hypertensive Athletes can be Reduced by Antihypertensive Medication Despite Continuing Intense Aerobic Exercise.

INTRODUCTION: Left ventricular hypertrophy (LVH) can be successfully reduced by antihypertensive medication. Both hypertension and aerobic exercise can cause increases in left ventricular mass (LV-mass). AIM: Therefore, hypertensive athletes with LVH were studied to investigate the effect of antihypertensive medication on LV-mass reduction despite continuing their regular intensive exercise programs. METHODS: 14 previously untreated hypertensive male athletes (A) with LVH and a prolonged history of endurance training where included in the study. 50 previously untreated inactive comparable hypertensives with LVH served as controls (C). For both groups inclusion criteria were blood pressure (BP) at rest: > 140/90 mmHg, BP during ergometry (at 100 W): > 200/100 mmHg and. LV-mass-index > 125 g/m2. Echocardiography was performed to calculate LV-mass and function before and after 3 years of antihypertensive medication. RESULTS: Despite regularly aerobic training throughout the treatment period, LV mass decreased from 164 ± 19 g/m2 before to 97 ± 16 g/m2 after 3 years of therapy (p < 0.001). Controls with identical pressures demonstrated a decrease from 149 ± 29 g/m2 to 87 ± 15 g m2. There were similar decreases in LV wall thicknesses in both groups, whereas diastolic dimensions did not change significantly. Moreover, there was an increase in fractional fiber shortening as a measure of LV pump function in both groups of 15% in A and 11% in C, respectively. CONCLUSIONS: In hypertensive athletes LVH due to hypertension can be reduced and LV-function can be improved by long-term antihypertensive medication despite regular aerobic exercise. Therefore, exercise does not interfere with the regression of LVH on account of antihypertensive therapy in hypertensive subjects.

Acute Effects of Moderate Continuous Training on Stress Test-Related Pulse Pressure and Wave Reflection in Healthy Men.

INTRODUCTION: Arterial dysfunction develops early in life even in individuals with modest cardiovascular risk. Stress is associated with increased risk in cardiovascular morbidity and mortality. AIM: The main objectives of this study were to investigate the acute effects of moderate continuous training (MCT) on established markers of arterial stiffness and cardiovascular risk during standardized cold pressor stress testing (CPT). METHODS: 29 young healthy male subjects (33.7 ± 8 years, BMI 24 ± 2 kg/m2) performed a 60-min period of moderate upright bicycle exercise with 65% of maximum heart rate. Before (t0), 45 (t45) as well as 60 (t60) min after exercise peripheral pulse pressure (PP) as well as augmentation index at a set heart rate (AIx@75) were assessed non-invasively at rest using an oscillometric device. Immediately after t0 and t60 PP and AIx@75 were registered at the end of a 2 min CPT. RESULTS: PP (p = 0.005) and AIx@75 (p = 0.04) were reduced below pre-exercise level at t60. In contrast to CPT before exercise, there were significant reductions in PP (p = 0.039) as well as AIx@75 (p = 0.002) during CPT after exercise. Additionally, there was a negative correlation between maximal oxygen consumption and AIx@75 (r = -0.42, p = 0.044). CONCLUSIONS: Acute MCT decreased PP and reduces AIx@75 after 60 min of recovery. Furthermore, PP and AIx@75 showed reduced values after completion of MCT indicating attenuated hemodynamic response to stress testing after MCT. Moreover, higher physical conditioning status was associated with more favorable effects on stress test-related arterial compliance.

Influence of a high-intensity interval training session on peripheral and central blood pressure at rest and during stress testing in healthy individuals.

BACKGROUND: Regular physical activity is known to reduce arterial pressure (BP). In a previous investigation, we could prove that even a single bout of moderate-intensity continuous exercise (MICE) causes a prolonged reduction in BP. Whether high-intensity interval training (HIIT) has a favourable influence on BP, and therefore may be followed subjects and methods by a prolonged BP reduction, should be examined on the basis of blood pressure response after exercise and during a subsequent stress test. PATIENTS AND METHODS: In 39 healthy men (aged 34 ± 8 years, BMI 24 ± 2), peripheral and central BP were measured noninvasively at rest and at the end of a 2-min cold pressor test (CPT) using a Mobil-O-Graph (24 PWA monitor, IEM). Following HIIT (6 x 1 min at 98% of the previously determined maximum wattage, 4-min rest between intervals) BP was measured again throughout 60 min of rest and thereafter during a CPT. The results were compared with those obtained before HIIT. RESULTS: Similar to MICE, peripheral and central BPs were significantly (p < 0.05) lower 45 min after HIIT. When analysing peripheral BP during a CPT before and after exercise, significantly lower systolic (p < 0.001) and diastolic (p = 0.008) pressures were established after HIIT. This was true for systolic (p = 0.002) and diastolic (p = 0.006) central BP as well. Although there were no more significant differences between pressures at rest before and 60 min after exercise, the increase in peripheral systolic pressure due to CPT was significantly slower after HIIT (p = 0.019) when compared with BP during CPT before exercise. This was true for central systolic BP as well (p = 0.017). CONCLUSION: HIIT leads to a BP reduction, which can still be detected up to 45 min after completion of the training. Even 60 min after exercise, pressures during a CPT showed a reduced augmentation, indicating an attenuated hemodynamic response to stress testing after HIIT.

Favorable effect of aerobic exercise on arterial pressure and aortic pulse wave velocity during stress testing.

BACKGROUND: Increased central pulse wave velocity is a major risk factor for cardiovascular disease. The favorable influence of exercise on arterial stiffness (AS) and blood pressure (BP) has been reported exclusively at rest. The present study investigated the influence of a single bout of acute cycling on AS and BP during recovery and, moreover, during cold pressor stress testing. PROBANDS AND METHODS: 32 healthy men (33.7 ± 8 years, BMI 24 ± 2.5 kg/m²) performed a 60 minute endurance exercise on a bicycle ergometer (45 % VO2max). Before and after exercise aortic pulse wave velocity (aPWV) as well as central and peripheral BP were measured non-invasively at rest and at the end of a 2 minute cold pressor test (CPT). RESULTS: Even after 60 minutes of recovery aPWV (- 0.22 ± 0.3 m / sec) was significantly reduced (p < 0.01). Exercise decreased peripheral (- 8 ± 7 mmHg) and central (- 7 ± 8 mmHg) systolic BP as well as peripheral (- 3 ± 5 mmHg) and central (- 4 ± 7 mmHg) diastolic BP (p < 0.01). In comparison to measurements during CPT pre-exercise, there was a significant reduction in aPWV (- 0.19 ± 0.3 m / sec), peripheral (- 6 ± 10 mmHg) and central (- 5 ± 8 mmHg) systolic BP as well as peripheral (- 3 ± 6 mmHg) and central (- 3 ± 6 mmHg) diastolic BP during CPT after exercise (p < 0.01). CONCLUSIONS: The present study suggests that acute endurance exercise leads not only to decreased BP but even more reduces aPWV as a measure of AS even after 60 minutes of recovery. In particular, the investigation provides evidence that acute moderate-intensity exercise has a favorable effect on BP and aPWV during stress testing.

[Blood pressure measurement during ergometry]. / Blutdruckmessung während Ergometrie. Manche Hypertonie demaskiert sich erst unter Belastung.

Blood pressure measurement during ergometry makes it possible to investigate the blood pressure behavior during physical effort. It is considered an option for the early detection of arterial hypertension, for the reliable investigation of the efficacy of antihypertensive therapy also under conditions of effort, and for the prognostic assessment of sequelae and cardiovascular events. The method is simple and inexpensive, requires little expenditure of time, and produces readily reproducible results. The submaximal workload range permits a ready differentiation to be made between normotension and hypertension, while at the same time, this workload range mimics everyday bodily effort, and, in principle, can therefore be employed in all patients.

Regular exercise as an effective approach in antihypertensive therapy.

PURPOSE: Exercise has been well documented to exert a beneficial effect on cardiovascular health. The effective control of arterial pressure (BP) is essential from the standpoint of cardiovascular prevention. So far, no study has determined the long-term effect of regular training as a monotherapy on both BP at rest and during exercise. METHODS: Therefore, 10 subjects with hypertension (aged 43 +/- 3 yr) were studied in order to define BP response to long-term aerobic training. BP measurements were obtained at rest and during ergometry (50-100 W). Patients were instructed to exercise weekly (2 x 60 min aerobic exercise). RESULTS: BP during exercise (100 W) did fall already after 6 months of regular training from 184 +/- 10/107 +/- 6 to 170 +/- 10/100 +/- 7, and this was associated with a 14% decrease in the rate-pressure product (at 100 W). After 18 months of training, there were further reductions in BP, at rest from 139 +/- 9/96 +/- 6 to 133 +/- 14/91 +/- 7 (P < 0.05) and during ergometry (100 W) from 184 +/- 10/107 +/- 6 to 172 +/- 8/96 +/- 6 mm Hg (P < 0.001). During a 3-yr follow-up, BP continued to decrease significantly to 130 +/- 13/87 +/- 7 mm Hg at rest and 167 +/- 9/92 +/- 6 mm Hg during exercise. No significant changes in body weight were documented during the training period. CONCLUSION: The data demonstrate that long-term aerobic exercise is associated with a decrease in BP at rest and during exercise, which is comparable to that of drug therapies. This antihypertensive effect of regular training can be maintained as long as 3 yr.