Volume High Intensity Interval Training Research Articles

The effect of low volume high-intensity interval training on metabolic and cardiorespiratory outcomes in patients with type 2 diabetes mellitus: A systematic review and meta-analysis.

The present systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted to investigate the effect of low volume high-intensity interval training (LVHIIT) on the metabolic and cardiorespiratory outcomes in patients with type 2 diabetes mellitus (T2DM). Relevant articles were sourced from PubMed, EBSCO, Web of Science, Embase, and the Cochrane Library from inception to October 2022. The study search strategy and all other processes were implemented in accordance with the PRISMA statement. Five randomized controlled trials that satisfied the inclusion criteria were included in this meta-analysis. The LVHIIT group had significantly lower fasting blood glucose levels (RR= -1.21; 95% CI= -2.02- -0.40, p = 0.0032) and HbA1c levels (RR= -0.65; 95% CI= -1.06- -0.23, p = 0.002) and higher levels of insulin resistance indicator HOMA-IR (RR= -1.34; 95% CI = -2.59- -0.10, p = 0.03) than the control group. Moreover, our results show that LVHIIT can reduce body mass (RR = -0.94, 95% CI = -1.37- -0.51, p<0.0001) and body mass index (RR = -0.31, 95% CI = -0.47- -0.16, p<0.0001). LVHIIT had a better therapeutic effect on blood lipid metabolism, such as total cholesterol, high-density lipoprotein, low-density lipoprotein and triglycerides. However, the change in fasting insulin levels was not statistically significant (RR= -1.43; 95% CI = -3.46- 0.60, p =0.17). Furthermore, LVHIIT reduced the systolic blood pressure (RR =-4.01, 95% CI = -4.82 - -3.21, p<0.0001) and improved peak oxygen uptake (VO2peak) compared to the control group (RR= 5.45; 95% CI = 1.38 - 9.52, p =0.009). After a certain period of LVHIIT, glycaemic control, insulin resistance, body weight, lipid profile and cardiorespiratory outcomes were significantly improved in T2DM patients.

High-intensity Interval Training In Patients With Coronary Artery Disease: A Randomized Controlled Trial

PURPOSE: Coronary artery disease (CAD) is the leading cause of mortality worldwide, and the prevalence is increasing. Cardiac rehabilitation is essential after a cardiac event with exercise training having a central role. Exercise training improves quality of life and reduces cardiovascular mortality and hospital admissions in CAD patients. We aimed to investigate the feasibility and efficiency of high-intensity interval training (HIIT) in patients with stable CAD. METHODS: In this randomized controlled trial, 142 patients with stable CAD and a mean age of 66.7 years completed the study, 64 in the HIIT group and 78 in the control group (CON). Patients were randomized 1:1 to supervised HIIT or standard care. HIIT was performed by training on a rowing ergometer 3 x week for 12 weeks. Patients in CON did not change their usual behavior, and all patients continued medications as prescribed before inclusion. Prior to randomization (baseline) and after 12 weeks (post-intervention), maximal oxygen consumption (VO2max), maximal pulmonary ventilation (VEmax) and maximal power output (Wmax) were determined in all patients. During the intervention period, the training load was defined as power output during training in week 3, 6 and 9. The average intensity was quantified and normalized to the average power that patients could sustain during a 5-min-all-out rowing performance test completed at week 5. RESULTS: Adherence to training was 97% (range 86-100%). Three patients dropped out because of non-fatal adverse events, and three patients reported non-severe self-limiting adverse events. The average relative power output was 72 ± 19% during warm-up and 117 ± 11 % during the interval bouts. Weekly training duration was on average 54 min. Compared to standard care, HIIT resulted in a significant (p < 0.001) greater increase in VO2max, VEmax, and Wmax (197 mL/min [160;233], 13 L/min [11;16], and 23 W [19;27]). CONCLUSIONS: Low volume HIIT performed as rowing significantly upregulated cardiorespiratory fitness (VO2max, VEmax, and Wmax) in patients with stable CAD compared to standard care. The exercise training on rowing ergometers was convenient and feasible for this frail patient group.

High-intensity interval training improves fat oxidation during submaximal exercise in active young men

This study aimed to examine the effects of four-weeks high-intensity interval training (HIIT) on fat oxidation responses during submaximal exercise in active young men. For this purpose, 20 active young men (who participated in the exercise three times per week) were divided into two groups, including a training group (age: 19.3±0.48 years, V̇O2peak 2.9±0.35 l/min, n=10) and a control group (age: 19.7±0.67 years, V̇O2peak 2.7±0.26 l/min, n=10). The training group performed high-intensity interval training for three sessions per week. Specifically, each session included 8-11 intensive cycling efforts comprising of 60 s duration. A 75 s low pedalling rate (30 W) was used as an active recovery between the intervals. Furthermore, a V̇O2peak test was performed prior to, at the end of two weeks and after the training period. Also, a 60 min constant cycling protocol was performed at ~60% V̇O2peak, in addition to the V̇O2peak test, before and after the training protocol. To assess plasma free fatty acids and glucose, blood samples were taken during a 60-min aerobic exercise prior to and following the training period. An increase (17.8%) in V̇O2peak was observed for the HIIT group after the training period compared to the control group (P&lt;0.05). The HIIT group performed the 60 min sub-maximal exercise test at a lower percentage of V̇O2peak, and decreases in the respiratory exchange ratio were greater in the HIIT group than in the control group (P&lt;0.05). Compared to the pre-test values and control group results, the HIIT group used less carbohydrate and more lipid oxidation during submaximal exercise (P&lt;0.05). The present study’s results indicate that short-term low volume HIIT can increase aerobic capacity and fat oxidation during submaximal exercise.

A Study Using Power Cycling on the Affective Responses of a Low-Volume High-Intensity Interval Training to Male Subjects with Type 2 Diabetes in Different Physical Activity Status.

High-intensity interval training (HIIT) has been shown in studies to enhance glucose management and cardiovascular well-being in patients with type 2 diabetes. In this study, we used power cycling to assess the physical activity levels of men with type 2 diabetes during a single low-volume HIIT session. First, fifty-six men with type 2 diabetes volunteered to take part in the study, and they were split into two groups based on the International Physical Activity Scale Short Form (IPA). To the first 1–4 labor bouts, both the sufficiently physically active and insufficiently physically active groups exhibited equal positive emotional reactions (p > 0.05). However, over time (about 5–10 times), both of them showed reduced emotional reactions, with a significant difference (p < 0.01). The insufficiently physically active group had lower mean emotional response, lowest effective response, and maximum effective response values than the sufficiently physically active group (p < 0.001), while the difference in RPE between the two groups was not statistically significant (p > 0.05). From the standpoint of emotional response, the proposed model shows that HIIT or reduced volume HIIT exercise prescriptions should be utilized with caution in physical activity programs for novices and less active and chronically sick persons. The frequency, intensity, and effects of low-volume HIIT on individuals' emotional reactions and health conditions in the T2DM group are also investigated. Furthermore, this low-volume HIIT program can be successfully applied in the real-world setting of people who are not physically active enough or who are chronically unwell.

Effects of very low volume high intensity versus moderate intensity interval training in obese metabolic syndrome patients: a randomized controlled study

Physical activity is a cornerstone in the treatment of obesity and metabolic syndrome (MetS). Given the leading physical activity barrier of time commitment and safety concerns about vigorous exercise in high-risk groups, this study aimed to investigate the effects of two extremely time-efficient training protocols (< 30 min time effort per week), either performed as high- (HIIT) or moderate-intensity interval training (MIIT) over 12 weeks, in obese MetS patients. In total, 117 patients (49.8 ± 13.6 years, BMI: 38.2 ± 6.2 kg/m2) were randomized to HIIT (n = 40), MIIT (n = 37) or an inactive control group (n = 40). All groups received nutritional counseling to support weight loss. Maximal oxygen uptake (VO2max), MetS severity (MetS z-score), body composition and quality of life (QoL) were assessed pre-and post-intervention. All groups significantly reduced body weight (~ 3%) but only the exercise groups improved VO2max, MetS z-score and QoL. VO2max (HIIT: + 3.1 mL/kg/min, p < 0.001; MIIT: + 1.2 mL/kg/min, p < 0.05) and MetS z-score (HIIT: − 1.8 units, p < 0.001; MIIT: − 1.2 units, p < 0.01) improved in an exercise intensity-dependent manner. In conclusion, extremely low-volume interval training, even when done at moderate intensity, is sufficiently effective to improve cardiometabolic health in obese MetS patients. These findings underpin the crucial role of exercise in the treatment of obesity and MetS.

Aging Liver: Can Exercise be a Better Way to Delay the Process than Nutritional and Pharmacological Intervention? Focus on Lipid Metabolism.

Nowadays, the world is facing a common problem that the population aging process is accelerating. How to delay metabolic disorders in middle-aged and elderly people, has become a hot scientific and social issue worthy of attention. The liver plays an important role in lipid metabolism, and abnormal lipid metabolism may lead to liver diseases. Exercise is an easily controlled and implemented intervention, which has attracted extensive attention in improving the health of liver lipid metabolism in the elderly. This article reviewed the body aging process, changes of lipid metabolism in the aging liver, and the mechanism and effects of different interventions on lipid metabolism in the aging liver, especially focusing on exercise intervention. A literature search was performed using PubMed-NCBI, EBSCO Host and Web of Science, and also a report from WHO. In total, 143 studies were included from 1986 to 15 February 2020. Nutritional and pharmacological interventions can improve liver disorders, and nutritional interventions are less risky relatively. Exercise intervention can prevent and improve age-related liver disease, especially the best high-intensity interval training intensity and duration is expected to be one of the research directions in the future.

Low volume high intensity interval training leads to improved asthma control in adults

Objective Regularly engaging in aerobic exercise is associated with improved asthma control and quality of life in adults with mild to moderate severity asthma. Previous intervention research has primarily employed moderate intensity continuous aerobic exercise protocols. As such, the impact of high intensity interval training (HIIT) on asthma control is poorly understood. Methods A six-week, low volume HIIT intervention (3 times/week, 20 min bouts) was conducted in adults with asthma (n = 20). Asthma control was assessed using the Asthma Control Questionnaire-7 (ACQ-7). Results ACQ-7 improved from pre to post-intervention (pre: 0.8 ± 0.6; post: 0.5 ± 0.4, p = 0.02, Cohens d = 0.5). In total, 7/20 (35%) participants experienced clinically meaningful improvements in ACQ-7. Conclusion A low-volume HIIT intervention led to statistically and clinically significant improvements in asthma control as well as improved exertional dyspnea and exercise enjoyment.

Effect of Different HIIT Protocols on the Glycemic Control and Lipids Profile in Men with type 2 diabetes: A Randomize Control Trial

Objective: : High intensity interval training (HIITs) can induce weight control, lowering blood pressure and beneficial effects on cardiovascular health in type 2 diabetic patients. The effect of different volumes of these exercises is unclear in type 2 diabetic patients. The aim of this study was to compare the effect of low volume and high volume of short-term intensive training on glycemic indexes of men with type 2 diabetes. Materials and Methods: Thirty type 2 diabetes male patients who were referred to Yazd diabetes research center (30 - 46 years old) were selected and randomly divided into 3 groups of low and high volume HIITs groups and control group. The intensity of the exercises in low volume was up to 110% and in high volume up to 80% of the maximum heart rate. The two training groups performed exercises 3 days of week for 8 weeks. Glycemic factors and lipids profile were measured before and after the last training session. Data were analyzed by covariance and paired T-test. Results: Low volume HIIT exercises significantly decreased the glucose ( P -value: 0.01), HbA1c ( P -value: 0.01), insulin ( P -value: 0.005), insulin resistance ( P -value: 0.001), and triglyceride ( P -value: 0.04). Low volume HIIT in the insulin resistance had a significant difference with the control group ( P -value: 0.04). High density lipoprotein in high volume group had a significant difference with the control group ( P -value: 0.021). Conclusion: Low-volume HIIT exercises can be a nonpharmacological approach to improving glycemic factors in type 2 diabetic patients.

High Intensity Interval Training (HIIT) Improves Cardiorespiratory Fitness (CRF) in Healthy, Overweight and Obese Adolescents: A Systematic Review and Meta-Analysis of Controlled Studies.

Background: High Intensity Interval Training (HIIT) is a sustainable and effective method for improving Cardiorespiratory Fitness (CRF) in adolescents. HIIT is proven to produce equal or greater improvements in CRF when compared to moderate intensity continuous exercise (MICE) in adolescents. Methods: The studies included were considered eligible if: (1) Participants were adolescents (11–18 years old); (2) Examined changes in CRF measured either directly or indirectly; (3) Included a non-exercising control group or MICE comparison group; (4) Participants were matched at enrolment; (5) Reported HIIT protocol information; (6) Provided HIIT intensity. A meta-analysis was conducted to determine the effect of HIIT on CRF. Meta-regression and moderator analyses were performed out to quantitatively examine moderators of protocol design on CRF improvements. Results: HIIT displays a moderate effect to improve CRF (g = 0.86, 95% CI 0.518–1.106, p < 0.001). Neither study duration (weeks), nor total or weekly accumulated HIIT volume (min) displayed any significant moderation effect on pooled improvement on CRF (p > 0.05). Conclusions: HIIT is an effective method to improve CRF in adolescents, irrespective of body composition. Notably, meta regression analysis identified that prolonged high volume HIIT programs are similarly effective to short term low volume HIIT programs. This becomes of particular interest for those involved in school curricula, where short HIIT exercise may provide a pragmatic adjunct to the health benefits of Physical Education (PE) lessons.

Effect of the Low or High Volume of High-Intensity Interval Training Protocols on the Leptin and Lipid Profile in Men with Type 2 Diabetes

Introduction: Sport activity leads to metabolic and physiological adaptations, which may have a beneficial role for diabetic patients. The purpose of this study was to compare the effects of low volume and high volume high-intensity interval training (HIIT) on serum leptin and some of the lipid profiles of type 2 diabetic men. Materials and Method: In this randomized clinical trial, 30 males with type 2 diabetes mellitus were divided into three groups of 10, including low volume and high volume HIIT and control groups. The low volume groups underwent intensive training for up to two minutes and a high volume group up to six minutes for 8 weeks. Blood lipid profile indicators were measured before and 48 hours after the last exercise session. The paired t-test, ANCOVA and LSD as a post hoc test were used to analyze the data. Results: There was a significant difference before and after 8 weeks of low-volume HIIT training at triglyceride (p = 0.049). However, there was no significant difference in serum leptin, cholesterol, LDL-C, and HDL-C in men with type 2 diabetes (p &gt; 0.05). ANCOVA only found a differences between groups on BMI (F2, 26 = 3.61, p = 0.041). Also, the post hoc in two by two comparisons of HDL showed that there was a significant difference between high volume HIIT and control groups (p = 0.021) and low volume and control group (p = 0.011). The HDL-C levels in HIIT training groups increased significantly compared to controls. Discussion: Considering other proven adaptations of HIIT training on triglyceride, HDL and improving glycemic indexes is a useful and safe training for type 2 diabetic patients. Therefore, needing a very short time for this training, metabolic, functional and physiological adaptations of HIIT training, along with other exercises are recommended to improve the condition and reduce the risk of cardiovascular disease and complications of type 2 diabetes

High-intensity interval training irrespective of its intensity improves markers of blood fluidity in hypertensive patients

ABSTRACTAim: The present study examined and compared the effects of two different HIIT (High-intensity interval training) protocols on markers of blood fluidity in hypertensive patients.Methods: Thirty hypertensive (stage 1, systolic BP >140 and diastolic BP>90 mmHg) patients (age, 47.96 ± 3.20 yrs), were randomly allocated to short-duration HIIT (SDHIIT, n = 10), long-duration HIIT (LDHIIT, n = 10), and control (n = 10) groups. After 2 weeks of continuous mild training, patients in SDHIIT group performed 8 weeks of HIIT included 27 min HIIT that encompassed 27 repetitions of 30 s activity at 80%-100% of VO2peak interspersed by 30 s passive/active (10%-20% of VO2peak) recovery, while, patients in LDHIIT group performed 8 weeks of HIIT (32 min per session) included 4 repetitions of 4 min activity at 75%-90% of VO2peak interspersed by 4 min passive/active (15%-30% of VO2peak) recovery. Two blood samples were taken before and after training and were analyzed for hemorheological variables.Results: Significant (P < .05) reductions in systolic blood pressure (SBP), blood and plasma viscosity, fibrinogen concentration and red blood cell (RBC) aggregation (8–12%) were found following two training protocols (P < .05), though, the differences between adaptations were not statistically significant (P > .05). In addition, HIIT protocols increased RBC deformability significantly (P < .05), with no significant differences being observed between two protocols.Conclusion: It is concluded that HIIT training reduces SBP and markers of blood fluidity in patients with stage 1 hypertension irrespective of the HIIT intensity and duration. Therefore, this type of exercise training could be prescribed for improving the blood fluidity markers in hypertensive patients.

Effect Of Ethnicity On Change In Vo2max And Substrate Oxidation In Response To HIIT

INTRODUCTION: About 20% of adults meet the 2008 Physical Activity Guidelines and this lack of physical activity increases individuals' risk of heart disease, stroke, type-2 diabetes, and certain cancers which increases morbidity and all-cause mortality. Typically, moderate intensity continuous training (MICT) is prescribed to clients to improve overall fitness and health status, although a primary barrier to regular physical activity among sedentary individuals is lack of time. An alternative to MICT is high intensity interval training (HIIT) which significantly increases VO2max and fat oxidation, in turn improving exercise capacity and reducing health risks. One widely ignored aspect of individual response to exercise training is ethnicity, as there are minimal data examining the effect of ethnicity on responses to exercise training. PURPOSE: To determine if ethnicity alters adaptation to low volume HIIT in sedentary women. METHODS: Inactive, non-obese women (age and VO2max = 24.3 ± 4.1 yr and 29.1 ± 2.1 mL/kg/min) participated in 9 sessions over a 3-week period of cycling-based HIIT (8-10 1-minute bouts at 85% PPO interspersed with 75-sec recovery at 10% PPO). Participants were Caucasian (C) (n=6) or Hispanic (H) (n=4). To assess VO2max, the initial work rate began at 30 or 40 W for 2-min followed by a 15 or 20 W/min increase in power output until volitional exhaustion. To assess substrate oxidation, a 6-min warm up began at 10% PPO and subsequently work rate increased by 10% PPO every 5-min during 4 remaining stages. These variables were measured pre- and post-training. RESULTS: Training elicited a HR equal to 88-94% HRmax. Data showed an increase (p=0.016) in VO2max in C (30.5 ± 1.3 vs 32.6 ± 3.9 mL/kg/min, +7%) and H (27.7 ± 2.8 vs 31.7 ± 2.6 mL/kg/min, +14%) with no significant groupXtime interaction (p=0.35). There was a significant trainingXboutXgroup interaction for fat oxidation (p=0.005), carbohydrate oxidation (p=0.009), and RER (p=0.000). Data showed an increase in the rate of fat oxidation and a reduction in carbohydrate oxidation in response to training which differed based on ethnicity. CONCLUSION: These data show HIIT induces significant increases in VO2max which are slightly higher in H vs C. In addition, ethnicity seems to mediate changes in substrate metabolism after interval-based exercise.

Four Weeks of Low Volume High-Intensity Interval Training Has No Effect On VO2max

Four Weeks of Low Volume High-Intensity Interval Training Has No Effect On VO2max

Improved Maximal Oxygen Uptake Following High-intensity Interval Training Relates To An Increase In Blood Volume

Improved maximal oxygen uptake following high-intensity interval training relates to an increase in blood volume High-intensity interval training (HIT) is an effective training mode for improving maximal oxygen uptake (VO2max). As past research has focused on peripheral adaptations to HIT, little is known about central factors governing cardiac output and thus VO2max. PURPOSE: The aim of this study was to test the hypothesis that HIT-induced improvements in VO2max are accompanied by increases in blood volume (BV) and cardiac stroke volume. Further, we investigated if inter-individual differences in the increase in in VO2max could be attributed to changes in BV. METHODS: Twenty subjects (10 females, 10 males) participated in a 6-week long training intervention consisting of 3 HIT sessions per week. Each session comprised of three 30 s all-out sprints against a breaking force equivalent to 7.5% of body weight. The sprints were separated by 2 min rest. VO2max, peak exercise cardiac output and BV (measured with carbon monoxide rebreathing) was assessed before (PRE) and after (POST) the intervention. RESULTS: VO2max increased by 9% (44.9±7.9 to 48.7±7.8 mL/min/kg) from PRE to POST (P < 0.05) and the increase in BV was 5% (5.4±0.8 to 5.7±0.9 L, P < 0.05) with a corresponding increase in peak exercise stroke volume. Accounting for inter-individual variance, approximately 60% of the change in VO2max could be attributed to changes in BV. CONCLUSION: This is the first study to show that improvements in VO2max with HIT are associated with increased blood volume. This suggest that a large part of HIT-induced improvements in VO2max are mediated by increased oxygen delivery, which at least in part is due to increased blood volume.

Skeletal muscle metabolism in rats with low and high intrinsic aerobic capacity: Effect of aging and exercise training.

PurposeExercise training increases aerobic capacity and is beneficial for health, whereas low aerobic exercise capacity is a strong independent predictor of cardiovascular disease and premature death. The purpose of the present study was to determine the metabolic profiles in a rat model of inborn low versus high capacity runners (LCR/HCR) and to determine the effect of inborn aerobic capacity, aging, and exercise training on skeletal muscle metabolic profile.MethodsLCR/HCR rats were randomized to high intensity low volume interval treadmill training twice a week or sedentary control for 3 or 11 months before they were sacrificed, at 9 and 18 months of age, respectively. Magnetic resonance spectra were acquired from soleus muscle extracts, and partial least square discriminative analysis was used to determine the differences in metabolic profile.ResultsSedentary HCR rats had 54% and 30% higher VO2max compared to sedentary LCR rats at 9 months and 18 months, respectively. In HCR, exercise increased running speed significantly, and VO2max was higher at age of 9 months, compared to sedentary counterparts. In LCR, changes were small and did not reach the level of significance. The metabolic profile was significantly different in the LCR sedentary group compared to the HCR sedentary group at the age of 9 and 18 months, with higher glutamine and glutamate levels (9 months) and lower lactate level (18 months) in HCR. Irrespective of fitness level, aging was associated with increased soleus muscle concentrations of glycerophosphocholine and glucose. Interval training did not influence metabolic profiles in LCR or HCR rats at any age.ConclusionDifferences in inborn aerobic capacity gave the most marked contrasts in metabolic profile, there were also some changes with ageing. Low volume high intensity interval training twice a week had no detectable effect on metabolic profile.

Diets along with interval training regimes improves inflammatory & anti-inflammatory condition in obesity with type 2 diabetes subjects.

Different physical activities and diets change the regulation of inflammations in both type 2 diabetes (T2D) patients and obese individuals, but the effect of both (Physical activity and diet) on pro/anti-inflammations has remained unknown. We investigated pro/anti-inflammations control, cardiovascular function, and total physiological parameters before and after 24weeks of low volume high intensity interval training (HIIT) on a cycle ergometer along with four dietary regimes in obesity with T2D patients. 33 non-active obesity T2D patients (BMI ≥ 30) midges (47yrs. ± 5) were volunteered to participate and randomly divided into three experimental(n = 11) [(1) LCD = low Carbohydrate Diet, (2) LFD = Low Fat Diet and (3) HFD = High Fat Diet)] and one control (n = 9) [ND = normal diet] groups. The whole groups performed underwent 8-week dietary regimes and then performed 3days/weeks (3 set 10 × 60s) HIIT on a cycle ergometer for 12weeks, which followed by a 4-week diet period again. Also, prior to and after 8weeks diet-12weeks High Intensity Interval Training (HIIT) and 4weeks diet 2-h oral glucose tolerance test (OGTT), resting blood pressure, incremental maximal oxygen uptake (VO2peak) cycle ergometer test and blood sample was collected from the subjects in order to measure pro/anti-inflammatory cytokines (IL-6, TNF-α, leptin, resistin, adiponectin, and FGF21). After 24weeks of intervention, the results indicated that the highest improvement in the percentage of changes in glucose happened in LCD (-34.76), insulin in ND (+16.43), cholesterol in LCD (-33.35), LDL in LFD (-9.14), HDL in LCD (+41.81), TG in LCD (-40.71), weight in LCD (-12.49) and HOMA-IR in HFD (-6.82). The results also indicated that after 24weeks of HIIT and diet interventions, highest benefit percentage change IL-6, resistin and leptin occurred in LCD (-32.10, -28.29 and - 53.92, respectively), TNF-α, FGF21 and adiponectin in LFD (-48.06, +55.30 and + 42.32, respectively). However, these changes were observed in other groups. These results demonstrated that HIIT along with low carbohydrate regimes improves overall cardiovascular parameters and reduce pro-inflammatory markers and increase anti-inflammatory markers in type 2 diabetic patients. Additionally, as with HIIT along with low carbohydrate, HIIT coupled with low fat would improve inflammation markers, though these effects were less significant. These findings suggest that HIIT along with low carbohydrate is a beneficial exercise and dietary strategy in T2D patients.

Feasibility Of A Low Volume HIIT Intervention In HIV+ Hispanic Women With Neurocognitive Impairment

High intensity interval training (HIIT) is safe and improves cardiorespiratory fitness and other health characteristics in people living with chronic diseases. However, the feasibility of such intervention among HIV+ women with neurocognitive impairment (NCI) have not been tested. PURPOSE: To determine feasibility (attendance and percent completion) of a low-volume HIIT (LV-HIIT) intervention among HIV+ Hispanic women with and without NCI compared with HIV- women. Also, to evaluate between group differences in HR response during the intervention. METHODS: 30 HIV+ with and without NCI (19 and 11, respectively), and 13 HIV- women volunteered for a 6-week, days/week LV-HIIT intervention on a cycle ergometer. During the first 2-weeks, participants completed 8-intervals (1-min intense, 1-min active resting) of cycling at 80% of their HR reserve (HRR) determined in a maximal exercise test. During the last 4-weeks, they completed 10-intervals at 90% of their HRR. Workloads prescribed to reach target HR ranged from 60 to 115, and 40 to 135 W in HIV+ and HIV- participants, respectively (P=0.54). Each session began with a 5-min warm-up on a cycle ergometer with no resistance, and ended with a 5-10 min cool-down with stretching exercises. NCI was determined with a battery of neuro-psychological testing (7-domains). Kruskal-Wallis non-parametric test was used to determine between group differences. RESULTS: 14 HIV+ with NCI (74%), 5 HIV+ without NCI (45%), and 11 HIV- (85%) Hispanic women completed the intervention; all with 100% attendance. Mean workload and percent target HR achieved were not different between HIV+ and HIV- participants (94±20 vs. 92±27 W, P=0.54; 95±6 vs. 100±17 %, P=0.69). Mean HR during the first 2-weeks were: 117±21 bpm for the HIV+ with NCI, 120±9 bpm for the HIV+ without NCI, and 124±13 bpm for the HIV- (P= 0.34). During the last 4-weeks, HR was: 129±21 bpm for the HIV+ with NCI, 132±8 bpm for the HIV+ without NCI, and 142±21 bpm for the HIV- (P=0.36). CONCLUSION: Attendance and percent completion suggest the feasibility of the LV-HIIT intervention among HIV+ Hispanic women with NCI. Similar HR response between groups further suggest the feasibility and safety of the HIIT exercise intervention in these patients. The study was supported by NIMHD S21MD001830, R21MH095524, U54-MD007587-04, R25MD007607.

Does Low Volume High-Intensity Interval Training Elicit Superior Benefits to Continuous Low to Moderate-Intensity Training in Cancer Survivors?

Does Low Volume High-Intensity Interval Training Elicit Superior Benefits to Continuous Low to Moderate-Intensity Training in Cancer Survivors?

Does low volume high-intensity interval training elicit superior benefits to continuous low to moderate-intensity training in cancer survivors?

AIMTo determine the impact of low volume high-intensity interval training (LVHIIT) and continuous low to moderate-intensity exercise training (CLMIT) on cardiovascular disease (CVD) risk and health outcomes in cancer survivors.METHODSSedentary cancer survivors (n = 75, aged 51 ± 12 year) within 24 months of diagnosis, were randomised into three groups for 12 wk of LVHIIT (n = 25), CLMIT (n = 25) or control group (n = 25). The exercise intervention involved 36 sessions (three sessions per week). The LVHIIT group performed 7 x 30 s intervals (≥ 85% predicted maximal heart rate) with a 60 s rest between intervals, and the CLMIT group performed continuous aerobic training for 20 min (≤ 55% predicted maximal heart rate) on a stationary bike. Outcome variables were measured at baseline and at 12 weeks and analysed using a 3 x 2 (group x time) repeated measures ANCOVA to evaluate main and interaction effects.RESULTSSignificant improvements (time) were observed for seven of the 22 variables (ES 0.35-0.97, P ≤ 0.05). There was an interaction effect (P < 0.01) after 12 wk in the LVHIIT group for six-minute walk test (P < 0.01; d = 0.97; 95%CI: 0.36, 1.56; large), sit to stand test (P < 0.01; d = -0.83; 95%CI: -1.40, -0.22; large ) and waist circumference reduction (P = 0.01; d = -0.48; 95%CI: -1.10, 0.10; medium). An interaction effect (P < 0.01) was also observed for quality of life in both the LVHIIT (d = 1.11; 95%CI: 0.50, 1.72; large) and CLMIT (d = 0.57; 95%CI: -0.00, 1.20; moderate) compared with the control group (d = -0.15; 95%CI: -0.95, 0.65; trivial).CONCLUSIONLow-volume high-intensity training shows promise as an effective exercise prescription within the cancer population, showing greater improvements in cardio-respiratory fitness, lower body strength and waist circumference compared with traditional CLMIT and control groups. Both LVHIIT and CLMIT improved quality of life. A proposed benefit of LVHIIT is the short duration (3 min) of exercise required, which may entice more cancer survivors to participate in exercise, improving health outcomes and lowing the risk of CVD.

Change in Maximal Fat Oxidation in Individuals in Response to Different Regimes of High Intensity Interval Training (HIIT)

INTRODUCTION: Increased capacity for fat oxidation (FatOx) is widely reported (Talanian et al. 2007; Burgomaster et al. 2008) in response to high intensity interval training (HIIT). However, most of these data was obtained in studies in which a non-exercising control group (CON) was not used. Based on the widespread variability in FatOx reported (Croci et al. 2014), it is unknown if these previously-reported increases in FatOx are real or a product of day-to-day variability in the measure. OBJECTIVE: To examine changes in FatOx and maximal fat oxidation (MFO) in response to 20 sessions of HIIT varying in structure in active men and women. METHODS: Thirty-nine active men and women (age and VO2max = 22.5 ± 4.4 yr and 40.0 ± 5.6 mL/kg/min) completed progressive HIIT, and 34 men and women matched for body fat and VO2max served as a non-exercising control group (CON). Ten sessions of low volume HIIT (8 – 10 1 min bouts at 90 – 110 % peak power output separated by 75 s recovery) were performed on a cycle ergometer after which subjects were randomly assigned to complete 10 additional HIIT sessions consisting of sprint interval training (SIT), high-volume HIIT, or periodized HIIT. After an overnight fast and 24 h dietary standardization, individuals underwent progressive cycling to exhaustion before, midway, and post-training to assess MFO, FatOx and carbohydrate oxidation (CHOOx). RESULTS: Results showed no effect of training on MFO (p = 0.11) although small increases in FatOx equal to an additional 4.3 g of fat were evident (p = 0.03). Individual responses in MFO occurred as 33 % of participants revealed meaningful increases in MFO from pre- to post-HIIT, and there was a significant inverse association between baseline MFO and the training-induced change, r = -0.46, p = 0.004. There was no time X training interaction for CHOOx (p = 0.31) suggesting a similar response of CHOOx to HIIT versus CON. CONCLUSIONS: Data refute previously-reported increases in MFO in response to HIIT (Astorino et al. 2013), although participants with low initial MFO tended to show meaningful increases in MFO with training. We recommend that scientists use a non-exercising control group to certify that the frequently-reported increase in FatOx attributed to HIIT is indeed a result of training and not due to marked variability in the measure.