Comparison of the Effects of LISS (Low-Intensity Steady State) and HIIT (High-Intensity Interval Training) on Cardiovascular Adaptation

High Intensity Interval Training in Patients With Cardiovascular Disease: A Brief Review of Physiologic Adaptations and Suggestions for Future Research

Background: Stair climbing is an effective, easy to approach and inexpensive moderate to high intensity exercise with great effects in improving functional status of individuals.High intensity interval training (HIIT) protocol is also a short time exercise with greater long term effects in improving cardiopulmonary endurance. Aim: To examine the effects of stair climbing on cardiopulmonary endurance in gym users in addition to High intensity interval training (HIIT) protocol and to measure the effects of stair climbing on blood lactate in gym users. Methods: 32 healthy individuals including males and females have been divided into two groups all the participants were gym users from past three months .Control group followed HITT protocol only and experimental group performed stair climbing in addition to HIIT protocol. Time duration of the training was 8 weeks .Individuals were assessed before and after the training for VO2max, and blood lactate. Body Mass Index, Rate of Perceived Exertion, and O2cost, modified Canadian Aerobic Fitness Test (mCAFT) stages Blood Pressure, Heart Rate has also been assessed before and after training. Results: Results has shown the significant increase in VO2 max (p value 0.001) and lower levels of blood lactate (≤0.001) within the groups after training. There was no significant improvement in VO2max and blood lactate formation on comparison between the groups. Conclusion: Current study concluded that there was significant increase in VO2 max and blood lactate with stair climbing in addition to HIIT protocol in gym users within the groups but there is no significance between the groups. It means both the protocols been followed are significant with almost equal affects and both are equally beneficial. Keywords: Stair Climbing Training, High intensity interval training (HIIT), modified Canadian Aerobic Fitness Test (mCAFT)

Background: Cardiovascular fitness, measured through Resting Heart Rate (RHR) and Maximal Oxygen Uptake (VO2 Max), is critical for optimizing athletic performance. High-Intensity Interval Training (HIIT) and Fast Continuous Training (FCT) are two aerobic conditioning modalities widely used to improve cardiovascular efficiency, but their comparative effects remain insufficiently studied in adult competitive athletes. Aim: This study aimed to compare the effects of an 8-week HIIT and FCT program on RHR and VO2 Max in adult athletes, thereby evaluating the efficacy of each training modality in enhancing aerobic performance. Methods: A randomized controlled trial design was employed involving 90 adult athletes (45 males and 45 females, aged 21-26), randomly located into three groups: HIIT (n=30), FCT (n=30), and Control (n=30). RHR and VO2 Max were assessed during pre- and post-intervention using Polar H10 monitors and Vmax Encore Metabolic Cart, respectively. Data were analysed using ANCOVA (Analysis of Covariance) to control for pre-test differences, followed by Tukey’s post-hoc comparison. Results: Post-intervention results revealed statistically significant improvements in both RHR and VO2 Max across the training groups (p < 0.05). The HIIT group exhibited the most significant reduction in RHR (62.72 bpm) and the highest increase in VO2 Max (52.12 ml/kg/min), outperforming both FCT (RHR = 65.06 bpm; VO2 Max = 49.40 ml/kg/min) and the Control group (RHR = 70.32 bpm; VO2 Max = 41.28 ml/kg/min). Effect sizes were large for both RHR (η² = 0.950) and VO2 Max (η² = 0.982), indicating robust model fit. Conclusion: The findings confirm that both HIIT and FCT are effective in improving cardiovascular parameters among adult athletes, with HIIT demonstrating superior efficacy in a shorter duration. These results support the strategic incorporation of HIIT in training regimens aimed at maximizing aerobic performance and cardiovascular health.

A previous study showed the importance of physical exercise in improving heart rate (HR) and blood pressure (BP) at rest. Studies have shown that resting HR is an independent predictor...

Background: Stroke survivors often face significant challenges in regaining cardiovascular health, with exercise being a key component of rehabilitation. High-Intensity Interval Training (HIIT) and Traditional Aerobic Exercise are two prominent modalities aimed at improving cardiovascular outcomes in this population. Objective: The study aimed to compare the effects of HIIT and Traditional Aerobic Exercise on cardiovascular health in stroke survivors. Methods: This randomized clinical trial enrolled 46 stroke survivors, equally divided into HIIT and Traditional Aerobic Exercise groups. The study took place at Sadique Polly Clinic, Nawab Town, Lahore, Pakistan. Participants underwent baseline assessments for resting heart rate, systolic and diastolic blood pressure, and total cholesterol levels. Post-intervention, these parameters were re-evaluated. Data analysis involved using SPSS version 25 to compare the effects of the two exercise modalities on cardiovascular health outcomes. Results: Both groups demonstrated improvements in cardiovascular health, but the HIIT group showed a more significant reduction in resting heart rate (change of -5.7 ± 2.9 bpm) compared to the Traditional Aerobic Exercise group (change of -3.9 ± 2.4 bpm), with a p-value of 0.03. Changes in systolic blood pressure (-9.2 ± 4.3 mmHg in HIIT vs. -7.6 ± 3.8 mmHg in Traditional), diastolic blood pressure (-4.3 ± 2.1 mmHg in HIIT vs. -3.7 ± 1.9 mmHg in Traditional), and total cholesterol levels (-11.1 ± 5.2 mg/dL in HIIT vs. -9.5 ± 4.7 mg/dL in Traditional) were observed in both groups but did not reach statistical significance (p > 0.05). Conclusion: Both HIIT and Traditional Aerobic Exercise are effective in enhancing cardiovascular health in stroke survivors. However, HIIT may offer a greater advantage in reducing resting heart rate compared to Traditional Aerobic Exercise.

Background: Exercise is a crucial component of cardiac rehabilitation for patients with Coronary Artery Disease (CAD). High-Intensity Interval Training (HIIT) and Moderate-Intensity Continuous Training (MICT) are two commonly used exercise modalities, but their comparative effectiveness in improving cardiovascular fitness in CAD patients remains uncertain.Objective: To compare the effects of HIIT and MICT on cardiovascular fitness in patients with CAD.Methods: A randomized controlled trial was conducted at Therapy Plus Clinics, Architect Society, Lahore, Pakistan, with 44 participants (22 in each group). Participants were randomly assigned to either HIIT or MICT for a 12-week intervention. Cardiovascular fitness was assessed using VO₂ max, resting heart rate, and blood pressure measurements before and after the intervention. Data analysis was performed to compare the outcomes between the two groups.Results: The HIIT group showed a significant improvement in VO₂ max (25.2 ± 3.5 to 30.4 ± 4.2 mL/kg/min) compared to the MICT group (24.8 ± 3.7 to 27.2 ± 3.9 mL/kg/min, p = 0.01). Additionally, the HIIT group experienced a greater reduction in resting heart rate (72.5 ± 8.2 to 68.1 ± 7.9 bpm) compared to the MICT group (73.2 ± 7.8 to 70.3 ± 7.5 bpm, p = 0.04). Both groups showed reductions in systolic and diastolic blood pressures, but the differences were not statistically significant.Conclusion: HIIT appears to be more effective than MICT in improving cardiovascular fitness, as evidenced by greater enhancements in VO₂ max and reductions in resting heart rate. These findings suggest that HIIT may be a superior exercise modality for CAD patients, offering a time-efficient alternative to traditional moderate-intensity exercise. Further research is needed to explore long-term effects and broader applicability.

Exercise with HICT methods is not the only effort to prevent cardiovascular disease. The development of science and technology of sports has resulted in the latest innovations and discoveries such as High Intensity Interval Training (HIIT) method that can improve cardiovascular abilities. HIIT is more flexible to do than High Intensity Continous Training (HICT) method. The purpose of this study is to compare exercise with HIIT and HICT method. It is an experimental quasy using 32 swimming athletes who were divided into two groups and given different training to measure VO2max, heart rate recovery, and resting heart rate. Subjects did training for five weeks with a frequency of exercise five times a week. The results show an increase in VO2Max in the HIIT group (22.83%) compared to the continuous group (9.36%) with p<0.05. The decrease in heart rate recovery in the HIIT group (12.97%) compared to the HICT group (6.62%) with p<0.05. A decrease in the resting heart rate of the HIIT group (18.7%) compared to the HICT group (9.9%) with p<0.05.It can be concluded that HIIT method is better at increasing VO2max, decreasing heart rate recovery, and decreasing resting heart rate than the HICT method.

Data (Burgomaster et al. 2008; Astorino et al. 2013) demonstrate improved maximal oxygen uptake (VO2max) after 6 and 12 wk of high intensity interval training (HIIT) which enhances exercise performance and health status. A few studies (Daussin et al. 2008; MacPherson et al. 2011) document changes in cardiac output (CO) in response to HIIT in which increases in VO2max occurred, and their results are equivocal. PURPOSE: To examine changes in VO2max and CO in response to various regimes of HIIT. METHODS: Fifty active men and women were randomized to control (CON, n = 24, age = 25.3 ± 4.7 yr) or one of three HIIT regimes, HIIT + sprint interval training (SIT) (n = 10, age = 22.8 ± 7.0 yr), HIIT + HIIT (n = 8, age = 21.8 ± 2.2 yr), or HIIT + periodized training (PER) (n = 8, age = 24.4 ± 6.8 yr). Training was performed 3 d/wk for 6 wk, with 10 sessions of HIIT (6 – 10 bouts of cycling for 60 s separated by 75 s recovery at 90 – 110 % peak power output) completed followed by randomization to one of three regimes for the ensuing 3 wk of the study. VO2max was measured pre- and post-training during progressive exercise, during which pulmonary gas exchange data were obtained. Cardiac output, heart rate (HR), and stroke volume (SV) were continuously estimated using thoracic impedance (Physioflow Enduro). Participants maintained their habitual physical activity during the study, and prior to all assessments, they abstained from exercise for 48 h. RESULTS: VO2max was unchanged in CON, yet a significant groupXtime interaction (p < 0.01) was demonstrated showing higher VO2max in HIIT + SIT (2.85 ± 0.47 L/min to 3.08 ± 0.34 L/min), HIIT + HIIT (2.81 ± 0.62 L/min to 3.02 ± 0.73 L/min), and HIIT + PER (2.64 ± 0.77 L/min to 2.92 ± 0.78 L/min). A significant groupXtime interaction (p = 0.038) was revealed for HR in that it was higher through HIIT. Stroke volume differed across time (p = 0.009) but no interaction occurred (p = 0.31). Cardiac output differed across time (p = 0.006) and a significant groupXtime interaction (p = 0.032) was shown. Compared to CON (20.9 ± 3.3 L/min to 20.8 ± 3.2 L/min), CO was increased in HIIT + SIT (19.9 ± 2.5 L/min to 21.4 ± 1.0 L/min), HIIT + HIIT (21.1 ± 4.0 L/min to 22.2 ± 2.7 L/min), and HIIT + PER (20.0 ± 3.7 L/min to 21.6 ± 4.4 L/min). CONCLUSION: Similar increases in VO2max occur in response to various regimes of HIIT, with greater CO explaining this outcome.

BackgroundAs a novel and time-efficient exercise form, high-intensity interval training (HIIT) has shown great potential in improving health-related physical fitness among diverse populations. However, empirical evidence on its efficacy among the elderly has not been well summarized. This systematic review and meta-analysis aimed to determine the effect of HIIT interventions on the parameters related to physical fitness and health of older adults, including resting heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), cardiorespiratory fitness (CRF), body mass index (BMI), body fat percent (BF%), waist circumference (WC), muscular endurance (ME), muscular strength (MS), muscular power (MP), balance and flexibility, compared to non-exercise and other-exercise (e.g., moderate-intensity continuous training, resistance training) conditions.MethodsLiterature published from January 2000 to May 2023 was collected through extensive searches across eight databases and relevant review papers. Randomized controlled trials (RCTs) featuring a minimum 2-week exercise intervention for older adults (≥ 60 years) were included. The pooled effect size of Hedges’g was estimated using random-effects models in R. Meta-regression was performed for both categorical (health status, duration of training programme, and frequency) and continuous moderators (mean age, male rate, and attrition rate).ResultsForty-four eligible RCTs with 1863 participants (52.1% female; 60.5–81.2 years) were included in the quantitative analysis. Compared to non-exercise condition, HIIT significantly improved resting HR (g = -0.36, 95%CI = [-0.67, -0.05], P = 0.032), SBP (g = -0.29, 95%CI = [-0.54, -0.03], P = 0.008), CRF (g = 0.77, 95%CI = [0.51, 1.04], P < 0.001), BF% (g = -0.26, 95%CI = [-0.41, -0.11], P = 0.006), MS (g = 0.47, 95%CI = [0.23, 0.71], P = 0.004), ME (g = 0.65, 95%CI = [0.10, 1.19], P = 0.036), and balance (e.g., timed-up-and-go) (g = -0.79, 95%CI = [-1.19, -0.40], P = 0.035). Compared to other-exercise condition, HIIT significantly improved resting HR (g = -0.11, 95%CI = [-0.21, -0.01], P = 0.029), SBP (g = -0.14, 95%CI = [-0.28, -0.01], P = 0.038), and CRF (g = 0.23, 95%CI = [0.07, 0.38], P = 0.008). No significant difference was found between HIIT and non-exercise condition for DBP, BMI and WC, as well as between HIIT and other-exercise condition for DBP, BMI, BF%, WC, ME, and balance (all P > 0.05). Meta-regression indicated that mean age moderated the HIIT effect on resting HR (b = -0.02, P = 0.014; HIIT vs. other-exercise condition) and SBP (b = 0.03, P = 0.048; HIIT vs. non-exercise), and attrition rate moderated the effect on CRF (b = 0.03, P = 0.007; HIIT vs. non-exercise).ConclusionThis study supports the efficacy of HIIT in improving resting HR, SBP, CRF, BF%, MS, ME and balance among older adults. More empirical evidence is needed to determine the efficacy of HIIT for MP and flexibility in this population.Trial RegistrationPROSPERO CRD42022316246.

Introduction: Aerobic exercise generates increased cardiorespiratory fitness, which results in a protective factor for cardiovascular disease. High-intensity interval training (HIIT) might produce higher increases on cardiorespiratory fitness in comparison with moderate-intensity continuous training (MICT); however, current evidence is not conclusive.Objective: To compare the effects of a low-volume HIIT and a MICT on maximal oxygen consumption (VO2max), systolic blood pressure, and diastolic blood pressure during eight weeks in healthy men between 18 and 44 years of age.Materials and methods: We conducted a randomized controlled trial. Forty-four volunteers were randomized to HIIT (n=22) or MICT (n=22). Both groups performed 24 sessions on a treadmill. The HIIT group completed 15 bouts of 30 seconds (90-95%, maximal heart rate, HRmax), while the MICT group completed 40 minutes of continuous exercise (65-75% HRmax). The study is registered as a clinical trial via clinicaltrials.gov with identifier number: NCT02288403.Results: Intra-group analysis showed an increase in VO2max of 3.5 ml/kg/min [95% confidence interval (CI) 2.02 to 4.93; p=0.0001] in HIIT and 1.9 ml/kg/min (95% CI -0.98 to 4.82; p=0.18) in MICT. However, the difference between the two groups was not statistically significant (1.01 ml/kg/min. 95% CI -2.16 to 4.18, p=0.52). MICT generated a greater reduction in systolic blood pressure compared to HIIT (median 8 mm Hg; p<0.001). No statistically significant differences were found between the groups for DBP.Conclusions: Results indicated no significant change in VO2max with a low-volume HIIT protocol versus MICT after 24 sessions. In contrast, MICT provided a greater reduction in systolic blood pressure compared to HIIT

Despite the growing attention towards the efficacy of high-intensity interval training (HIIT) on older adult health, a consensus regarding the pleiotropic effects of HIIT in this population is yet to be reached. Previous studies have predominantly focused on specific outcomes or particular groups, lacking comprehensive analysis. We aimed to conduct a systematic evaluation of the impact of HIIT on body composition, cardiopulmonary function, and metabolic parameters in older adults. The databases searched included PubMed, Web of Science, Cochrane Library, Scopus, WanFang, and other relevant sources from the inception of the database until July 2023. Randomized controlled trials (RCTs) on the effects of HIIT on body shape, cardiopulmonary function, and metabolic parameters in the older adult were searched. A total of 87 RCTs meeting the criteria were included, involving 4,213 older adult people. Meta-analysis results showed that HIIT significantly improved body fat percentage (BF%) [MD: -1.63%, p = 0.005], maximal oxygen uptake (VO2max) [MD: 2.46 mL min-1 kg-1, p < 0.00001], maximal heart rate (HRmax) [MD: 2.83 beats min-1, p = 0.02], and high-density lipoprotein (HDL) levels [MD: 0.04mmol L-1, p = 0.002]. However, for systolic blood pressure (SBP) [MD: 0.49 mmHg, p = 0.60], resting heart rate (HRrest) [MD: -0.95 BPM -1, p = 0.24], triglycerides (TG) [tendency for MD: -0.02 mmol L-1, p = 0.61], low-density lipoprotein (LDL) [MD: -0.04 mmol L-1, p = 0.27] had no significant effect. Sensitivity analysis found that HIIT significantly improved waist circumference (WC) [MD: -1.89 cm, p = 0.17], diastolic blood pressure (DBP) [MD: -0.63 mmHg, p = 0.23], respiratory exchange rate (RER) [MD: 0.01, p = 0.20], total cholesterol (TC) [MD: 0.10 mmol L-1, p = 0.14], and fasting plasma glucose (FPG) [MD:-0.20 mmol L-1, p = 0.08], but the results lacked robustness. There was no significant improvement in DBP [MD: -0.63mmHg, p = 0.23] and body mass index (BMI) [MD: -0.36 kg m-2, p = 0.06]. HIIT has shown certain potential and advantages in improving the physical health of the older adult, especially in cardiopulmonary function. However, more high-quality studies are needed to confirm the effects of HIIT on the physical health of the older adult in the future. It also provides a reference for the clinical practice and family health management of HIIT in the older adult and the development of HIIT guidelines. https://www.crd.york.ac.uk/PROSPERO/myprospero, identifier CRD42023460252.

This research was carried out to find out the effect of training using the High Intensity Interval Training (HIIT) model on increasing VO2 Max in white water rafting athletes. This research design is an experimental pre-post design. This research used 28 white water rafting athletes, consisting of 16 male athletes and 12 female athletes. The athlete's age range is 16-22 years. All research subjects were in healthy condition. All subjects were given the same treatment, namely training using the HIIT model. Intervention with HIIT cardio training. The HIIT training model uses an intensity of 90-100% of Maximal Heart Rate (MHR). HIIT is done with a ratio of 30 seconds of exercise then 3 minutes of rest. Exercise uses an intensity of 90% MHR in the first week and will be increased every week until it reaches 100% MHR. Exercises were carried out for 6 weeks with a frequency of 4x per week. VO2 Max measurements are carried out using a multistage test instrument. In this research, it can be seen that HIIT exercise carried out for 6 weeks with a frequency of 4 times per week can increase athletes' VO2 Max. There is a significant difference in VO2 Max between male and female athletes with a difference test result of P &lt; 0.05. Exercise using the HIIT model which is carried out for 6 weeks with a frequency of 4x a week can increase the VO2 Max of white water rafting athletes. HIIT training can be used as a recommendation to increase VO2 Max for white water rafting athletes.

Small-sided games (SSG) are one of the training methods used by coaches to stimulate the technical, tactical, and physical components of futsal players. This study aims to determine the effect of small-sided games (SSG) training with high-intensity interval training (HIIT) on improving VO2 Max among futsal extracurricular students at SMAN 15 Garut. The issue addressed in this study is the suboptimal endurance level of many students involved in the futsal extracurricular program. The research used an experimental method with a one-group pre-test and post-test design. The sample consisted of 20 students. VO2Max measurements were conducted using the Bleep Test, a standard method for assessing aerobic capacity. Before the training program commenced, all participants underwent the Bleep Test to obtain baseline VO2Max values (pretest). The small-sided games training program was implemented over 14 sessions, with training frequency set at three times a week. Data analysis involved normality, homogeneity, and t-test, yielding a significant value of (p = 0.000) &lt; 0.05, indicating a significant increase in VO2 Max with an average post-test value of 39.720. These findings confirm that SSG training with HIIT can effectively improve cardiovascular endurance in high school futsal players. The high-intensity small-sided games training method had a significant effect on improving VO2Max in these students.

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. 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 [HR<inf>max</inf>], 60 s rest) in addition to the regular rowing training (3×/week MICT 70-90 min, ≈70% HR<inf>max</inf>). The CG completed the regular normal rowing training and, instead of the HIIT units, two additional MICT units (70-90 min, ≈70% HR<inf>max</inf>). Before and after the intervention period, hemodynamic parameters were recorded non-invasively in both groups. 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. 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.

Although aerobic exercise is the primary modality recommended for the treatment of hypertension, it remains unclear whether high-intensity all-out sprint interval training (SIT) can result in greater reductions of blood pressure (BP) and cardiorespiratory health. This systematic review aims to compare the impact of SIT versus Moderate-intensity continuous training (MICT) on improvements in resting systolic blood pressure (SBP), diastolic blood pressure (DBP) and maximal oxygen uptake (VO2 max) among adults. We conducted a systematic search of three online databases (PubMed, Embase, and Web of Science) from January 2000 to July 2023 to identify randomized controlled trials that compared the chronic effects of SIT versus MICT on BP in participants with high or normal blood pressure. We extracted information on participant characteristics, exercise protocols, BP outcomes, and intervention settings. Furthermore, the changes in VO2 max between the two groups were analyzed using a meta-analysis. The pooled results were presented as weighted means with 95% confidence intervals (CI). Out of the 1,874 studies initially were found, eight were included in this review, totaling 169 participants. A significant decrease in SBP (MD = -2.82 mmHg, 95% CI [-4.53 to -1.10], p=0.08, I2 =45%) was observed in the SIT group compared to before the training, but no significant decrease in DBP (MD = -0.75 mmHg, 95% CI [-1.92 to 0.42], p=0.16, I2 = 33%) was observed. In contrast, both SBP (MD = -3.00 mmHg, 95% CI [-5.31 to -0.69], p=0.68, I2 = 0%) and DBP (MD = -2.11 mmHg, 95% CI [-3.63 to -0.60], p=0.72, I2 = 0%) significantly decreased in the MICT group with low heterogeneity. No significant difference was found in resting SBP and DBP between SIT and MICT after the intervention. Both SIT and MICT significantly increased VO2 peak, with SIT resulting in a mean difference (MD) of 1.75 mL/kg/min (95% CI [0.39-3.10], p=0.02, I2 = 61%), and MICT resulting in a mean difference of 3.10 mL/kg/min (95% CI [1.03-5.18], p=0.007, I2 = 69%). MICT was more effective in improving VO2 peak (MD = -1.36 mL/kg/min, 95% CI [-2.31 to 0.40], p=0.56, I2 = 0%). Subgroup analysis of duration and single sprint time showed that SIT was more effective in reducing SBP when the duration was ≥8 weeks or when the sprint time was <30 s. Our meta-analysis showed that SIT is an effective intervention in reducing BP and improving cardiorespiratory fitness among adults. Consequently, SIT can be used in combination with traditional MICT to increase the variety, utility, and time efficiency of exercise prescriptions for different populations.