High-intensity Intermittent Training Group Research Articles

Comparative Effects of Two High-Intensity Intermittent Training Programs on Sub-Elite Male Basketball Referees' Fitness Levels.

This study aimed to compare the effects of an 8-week short-term training program, comprising repeated sprints or running-based high-intensity intermittent training (HIIT), on the aerobic fitness and repeated sprint ability (RSA) performance of sub-elite basketball referees. Twenty male referees participated in supervised training sessions twice a week. They were randomly assigned to either the RSA-based group (RSAG) or the running-based HIIT group (HIITG). The RSAG conducted 3-4 sets of 8 × 20-m all-out sprints, while the HIITG performed 2-3 sets of 6 × 20-s runs at 90% of their maximal velocity achieved in the 30-15 intermittent fitness test (30-15IFT). Referees underwent a graded exercise test on a treadmill, the 30-15IFT, and an RSA test before and after the training program. Both groups showed significant improvement (~3%) in the fastest (22.6 ± 1.4 vs. 23.4 ± 1.7 and 22.0 ±1.9 vs. 22.4 ± 1.7 km·h-1 in RSAG and HIITG, respectively) and mean (21.5 ± 1.2 vs. 22.4 ± 1.4 and 21.3 ± 1.8 vs. 21.7 ± 1.6 km·h-1 in RSAG and HIITG, respectively) sprint velocity of the RSA test (p < 0.05). Moreover, positive changes (p < 0.05) were observed in the 30-15IFT maximal velocity (18.6 ± 1.1 vs. 19.3 ± 1.0 and 19.4 ± 0.9 vs. 20.5 ± 0.9 km·h-1 in RSAG and HIITG, respectively). In conclusion, an 8-week training intervention using either RSA or running-based HIIT led to similar improvements in referees' RSA performance and specific aerobic fitness measures. These findings could assist in devising tailored training programs for basketball referees.

High-intensity interval training improves cognitive impairment of vascular dementia rats by up-regulating expression of brain-derived neurotrophic factor in the hippocampus.

The present study aims to investigate the effect and its potential mechanism of high-intensity intermittent training (HIIT) on cognitive function in vascular dementia (VD) rats. The VD rats with the cognitive impairment were induced by bilateral common carotid artery occlusion (BCCAO), and the ones in the moderate-intensity continuous training (MICT) group and HIIT group received MICT or HIIT for 5 consecutive weeks, respectively. The swimming speed, endurance, and grip strength of rats were all measured after training. The effect and mechanisms of HIIT on ameliorating the cognitive dysfunction were further evaluated by the Morris water maze test, histomorphological analysis, and Western blot analysis. As a result, no significant difference in motor function between VD rats and sham rats was observed. After 5-week HIIT, the motor function of VD rats was significantly enhanced. The results of the Morris water maze test revealed that HIIT significantly reduced escape latency as well as distance to find the platform compared with the sedentary control group (SED group), indicating the improvement in cognitive function. In addition, the hippocampal tissue damage of VD rats measured by H&E staining was markedly ameliorated after 5-week HIIT. Moreover, brain-derived neurotrophic factor (BDNF) expression level in the cerebral cortex and hippocampus tissue detected by Western blot were significantly up-regulated in HIIT group compared to SED group and MICT group. In conclusion, HIIT can improve BCCAO-induced cognitive impairment via up-regulating BDNF expression in VD rats.

Effects of MICT/HIIT on the ultrastructure of myocardium and soleus in rats with high-fat diet and its mechanisms

Objective: To investigate the effects of moderate intensity continuous training (MICT) and high intensity intermittent training (HIIT) on the ultrastructure of myocardium and soleus in rats with high fat diet, and to explore the mechanisms. Methods: 5-week-old male SD rats were randomly divided into normal diet quiet group (C), high-fat diet quiet group (F), high-fat MICT group (M) and high-fat HIIT group (H), with 8 rats in each group, and the fat content of the high-fat dietary feed was 45%. The M and H groups were given 12 weeks of treadmill running with an incline of 25°. The M group was given continuous exercise with 70%VO2max intensity, and the H group was given intermittent exercise with 5 min 40%~45%VO2max and 4 min 95%~99%VO2max intensity successively. After the intervention, the contents of free fatty acid (FFA), triglyceride (TG), high density lipoprotein cholesterol (HDL) and low density lipoprotein cholesterol (LDL) in serum were detected. Transmission electron microscopy was used to observe the ultrastructure of myocardium and soleus in rats. Western blot was used to detect the protein expressions of AMPK, malonyl-CoA decarboxylase (MCD) and carnitine palmitoyl transterase 1 (CPT-1) in myocardium and soleus. Results: Compared with C group, the body weight, Lee's index, the contents of LDL, TG and FFA in serum were increased, the content of HDL was decreased (P＜0.05), the protein expressions of AMPK and CPT-1 in myocardium and soleus were increased, the protein expression of MCD was decreased (P＜0.05), and the ultrastructure was damaged in group F. Compared with F group, the body weight and Lee's index were decreased, the contents of LDL and FFA in serum were decreased (P＜0.01), the protein expressions of AMPK, MCD and CPT-1 in myocardium were increased, and the protein expressions of AMPK and MCD in soleus were increased (P＜0.05), and the ultrastructural damage was attenuated in M and H groups. Compared with M group, the content of HDL in serum was increased (P＜0.01), the protein expressions of AMPK and MCD in myocardium were increased, and the ultrastructural damage was mild, the protein expression of AMPK in soleus was decreased, the protein expression of MCD in soleus was increased (P＜0.05), and the ultrastructural damage was severe in group H. Conclusion: MICT and HIIT have different effects on the ultrastructure of myocardium and soleus in high-fat diet rats by intervening the protein expression of AMPK, MCD and CPT-1.

Effects of Different Intensity Exercise on the Patients of Oxidative Stress Factors and Glycemic Control Type 2 Diabetes Mellitus

This study’s major purpose was to examine the impact of two various exercise intensities on glucagon-like peptide-1 and endoplasmic reticulum stress in teenagers with type 2 diabetes. Twenty teenagers with T2DM were recruited in the trial and randomly assigned to one of two groups: HIT (n = 10) or LIT (n = 10). At a heart rate of less than 45 percent, the low-intensity intense exercise group participated in aerobic activity training. Interval training with a heart rate reserve of at least 80% was used by the high-intensity intermittent training group. Both groups had the same weekly energy expenditure (1,200 kcal/week). The nositol required enzyme 1 and X-box binding protein-1 improved in both groups, but the difference in improvement between the two groups was not statistically significant. High-intensity interval training led to a significant decrease in body fat percentage among participants. After 12 weeks, the C-peptide levels had risen and varied considerably between the two groups. According to the homeostasis model assessment, there were significant differences between the groups in fasting glucose and insulin resistance, and leptin levels reduced after 12 weeks. The 12-week rise in glucagon-like peptide-1 was different across the groups. In teenagers with type 2 diabetes mellitus, high-intensity intermittent exercise training may enhance glycemic management, physical body composition, glucagon-like peptide-1, and endoplasmic reticulum stress.

Interleukin-15 and creatine kinase response to high-intensity intermittent exercise training

To verify the acute and chronic effects of high-intensity intermittent training (HIIT) on interleukin 15 (IL-15) response and the relationship between circulating IL-15 concentrations and muscle damage in young men. Physically active men performed two different training protocols at moderate and high intensity, three times per week for 5 weeks. Twenty subjects were randomly allocated into high-intensity intermittent training group (HIIT-5 km 1 min at 100% of maximal aerobic speed interspersed by 1 min passive recovery; n = 10) or moderate-intensity continuous training group (MICT-5 km 70% of maximal aerobic speed; n = 10). An acute exercise session was performed with blood sample collection pre-exercise, immediately post-exercise, and 60 min post-exercise (before and after 5 weeks of training). Blood samples were used to analyze serum IL-15 and creatine kinase (CK) concentrations. The results showed no changes in serum IL-15 concentrations independent of protocol, moment measurement, and intervention period. CK concentrations showed higher values post-exercise when compared to pre-exercise in both protocols. No significant relationship was found between serum IL-15 and CK concentrations. Our findings point to the absence of acute and chronic changes in serum IL-15 concentrations in response to 5 weeks of high-intensity intermittent training. In addition, data suggest that the release of this cytokine is not related to muscle damage in healthy young men.

Effects over 12 weeks of different types and durations of exercise intervention on body composition of young women with obesity

Summary Objective To provide basis for effective exercise intervention for young obese women through comparative study of three types of exercise intervention effects, namely, maximum fat oxidation intensity continuous aerobic training (FATmax AT), high intensity intermittent training (HIIT) and resistance training (RT), on body composition in different intervention durations. Methods Fifty-four eligible young obese women (BF% > 30%) aged 22.14 ± 1.32 years old were randomized to FATmax AT, HIIT or RT group. They respectively completed continuous aerobic, high intensity intermittent or anti-resistance exercise 3 sessions per week (45 min per session) for 12 weeks. Body fat rate (BF%), body fat mass (FM), fat-free mass (FFM) and muscle mass (MM) were measured at pre-mid- and post-intervention. Results (1) Significant interactions of group × time on BF% (F = 18.35, P = 0.00), FM (F = 13.96, P = 0.00), FFM (F = 21.55, P = 0.00) and MM (F = 8.17, P = 0.00) were found, but there is no main effect in either group or time factors. (2) BF% and FM of the participants in FATmax AT, HIIT and RT group decreased significantly when compared to pre-exercise session (P Conclusions This study shows that 12 weeks of exercise training (3 × 45 min/wk) are an efficient weight-reducing procedure, either with FATmax AT, HIIT or RT. Not surprisingly, the heavier protocol (45 min HIIT) induces a slightly greater reduction in BF% and increases FFM, while RT is most helpful in the increase of MM. Therefore, HIIT can be selected for people who can endure high-intensity exercise and are in urgent need of fat loss. However, since the three protocols are not matched for energy expenditure, no general conclusion about the superiority of one protocol over another can be given. A further study investigating this comparison with matched levels of energy expenditure will help to elucidate this question.

Serum levels of Insulin-like growth factor-1 (IGF-I) as an indicator associated with aerobic and anaerobic fitness assessment in adolescent boys

Background: Insulin-like growth factor -1 (IGF-I) has a variety of roles, But the abundance of scientific evidence indicates that it is a metabolic biomarker associated with indicators of physical fitness and health. The present study examined the relationship between serum levels of IGF-I and aerobic fitness, anaerobic capacity and body fat percent, systolic, and diastolic blood pressure before and after the eight weeks of high intensity intermittent training (HIIT) in adolescent boys. Methods: In this experimental study, 22 adolescent boys in a randomly and double-blinded design were allocated in two equal groups: HIIT group (N=11) and control group (N=11). Training programs were conducted 3-4 times per week for 8 weeks. The HIIT program consisted of 6-8 running sprints (30-60 seconds) with a 3.5-4 min recovery. Mentioned indicators assessments were performed 18-24 hours pre and post intervention. Results: IGF-1, Maximum Oxygen uptake (VO2max(, Peak Power Output (PPO) and mean power output (MPO) were significantly higher after 8 week HIIT than the pre-exercise training evaluations (P 0.05). Conclusion: The IGF-I can be used as an indicator to assess the fitness of adolescent boys.

PO-044 Effects of one-time high intensity intermittent training on the expression of UCP1 mRNA in adipose tissue of obese rats

Objective To observe the effect of one-time high-intensity intermittent training (HIIT) on the white fat browning in obese rats.&#x0D; Methods 12 obese male rats at the age of 19-week were randomly divided into control group (OC group, n=6) and HIIT group (n=6). OC group doesn’t do exercise, and HIIT group finish the once high-intensity intermittent training ( ①Warm up: 70%VO2max, 7min; ②High intensity exercise: 90%VO2max, 3min+ 50%VO2max, 3min, 6 times; ③Convalescence: 70%VO2max, 7min.). The maximal oxygen uptake (VO2max) of HIIT group was tested before training, and the exercise intensity was determined according to the average VO2max. The subcutaneous and testicle white adipose tissue (WAT) and brown adipose tissue (BAT) of the scapula were taken immediately after exercise. The expression of UCP1 mRNA in the WAT and BAT using the fluorescent quantitative PCR.&#x0D; Results Compared with the OC group, the expression of BAT UCP1 mRNA , in the HIIT group was increased, but there was no significant difference (1.40±0.50 vs 1.03±0.27, P&gt;0.05). In both OC and HIIT group, the expression of UCP1 mRNA of the subcutaneous and testicle WAT were too low to test. The results showed that one-time HIIT exercise had no effect on the expression of UCP1 mRNA in WAT.&#x0D; Conclusions The effects of One-time HIIT on the expression of UCP1 mRNA in adipose tissue of obese rats are still not definite.

PO-294 Effects of HIIT on FTO protein expression and its relationship with glucose and fat metabolism

Objective FTO (Fat mass and obesity-associated) is associated with increased risk of obesity and type 2 diabetes incurrence. Studies have shown that the expression of FTO protein in skeletal muscle and adipose tissue is related to the oxidation rate of whole body substrate. With the increase of age, the body's carbohydrate oxidation rate decreases, the fat oxidation rate increases, and at the meanwhile the expression of FTO protein in skeletal muscle decreases and that in adipose increases. HIIT is very helpful for inhibiting obesity, insulin resistance and type 2 diabetes. So the purpose of this study is to investigate the effect of HIIT exercise on the expression of FTO protein in rats and its relationship to glucose and fat metabolism.&#x0D; Methods 20 Male, 3-week-old SD rats were randomly divided into two groups, each group has 10 rats. C group: sedentary; HIIT group: high-intensity intermittent training group (85% ~ 90% VO2max exercise for 6min, 50% VO2max exercise interval 4min, repeated 6 times. 5 times/week ,4 weeks). All subjects were maintained in a free facility with constant temperature of 25°C, light-dark cycle of 12/12 h and free access to water. 48 hours after the last exercise, all samples were taken with an overnight fast. The expression of FTO protein in skeletal muscle and adipose tissue was measured by Western Blot. Serum insulin was tested by ELISA; Estimation of blood glucose was tested by Glucose oxidase method.&#x0D; Results 1.The expression of FTO protein in skeletal muscle was significantly higher than that of group C (P &lt;0.01); The expression of FTO protein in adipose tissue of HIIT group was significantly lower than that of group C (P &lt;0.05); 2. Serum insulin levels of group HIIT was significantly lower than that of group C (p &lt;0.01); And the blood glucose of group HIIT was significantly lower than that of group C (p &lt;0.01). 3. Serum LDL-C of group HIIT was significantly lower than that of group C (p &lt;0.01), and serum HDL-C of group HIIT was significantly higher than that of group C (p &lt;0.01);4. Correlation analysis showed that serum insulin level was negatively correlated with skeletal muscle FTO protein expression (R = -0.454, p &lt; 0.05). Correlation analysis showed that serum LDL-C levels was positively correlated with adipose tissue FTO protein expression (R=0.559, p &lt; 0.05) and serum HDL-C levels was negatively correlated with adipose tissue FTO protein expression (R=-0.474, p &lt; 0.05).&#x0D; Conclusions 1. HIIT can increase the protein expression of FTO in rat skeletal muscle and decrease the expression of FTO protein in adipose tissue; 2. HIIT can regulate glucose metabolism and lipid metabolism in rats; 3. The regulation of glucose metabolism by HIIT may be related to the increase of FTO protein expression in skeletal muscle. The regulation of lipid metabolism may be related to the reduction of FTO protein expression in adipose tissue.

PO-026 Effects of Different Exercise on the Expression of White Fat Browning Proteins in Growing Rats

Objective The prevention of obesity in children and adolescents can reduce the risk of obesity and various chronic diseases in adulthood. In recent years, it has been found that inducing browning of white fat can regulate energy balance and inhibit fat accumulation .Exercise as a healthy intervention can regulate energy balance by affecting the browning of white fat. However, the effect of exercise on the browning of white fat during the critical period of growth and development is not yet known, and the effect of different exercise methods on the browning of different location of white fat is inconsistent. Therefore, this study intends to explore the effects of different exercise methods on the expression of browning-related proteins of peripheral white adipose tissue and browning-related genes of hypothalamus in growing rats through animal experiments, and to explore the relationship between them.&#x0D; Methods 30 Male, 3-week-old SD rats were randomly divided into three groups, C group: Control group (sedentary, n=10);MD group: moderate-intensity training group (MD group, n=10), and high-intensity intermittent training group (HIIT group, n=10). MD group exercise program: 60% VO2max exercise for 60 minutes, 5 times a week for a total of 4 weeks. HIIT group exercise program: 85% ~ 90% VO2max exercise 6min, 50% VO2max exercise interval 4min, repeated 6 times. 5 times a week for a total of 4 weeks. The exercise intensity was adjusted based on the maximal oxygen uptake measurement every 2 weeks. Three groups of rats were weighed once a week. After the experiment, anesthesia was performed with 10% chloral hydrate 50 mg/Kg (body weight) in the abdominal cavity to rapidly separate the hypothalamus、Perirenal and epididymal fat and put into liquid nitrogen and transfer these to -80°C refrigerator for testing. The expression of POMC, NPY, LEPR and GRP78 mRNA in hypothalamus was determined by RT-PCR. The expression of PRDM16 and UCP1 protein in perirenal white fat was measured by Western Blot.&#x0D; Results 1. The weight of the three groups of rats increased continuously within 4 weeks of exercise intervention. Compared with group C,the weight of group E and group H increased slowly from the second week (p&lt;.05). 2. The increase in absolute weight and relative weight of visceral fat in MD group and HIIT group was significantly lower than that in C group (p&lt;.01); the increase in absolute weight and relative weight of visceral fat in MD group was significantly lower than HIIT group(p&lt;.05).3. Compared with group C, the expression of PRDM16 protein in WAT of the kidneys in group MD was significantly increased (p&lt;.01), and the UCP1 protein expression was significantly increased (p&lt;.01). Compared with group C, there was no significant difference in PRDM16 and UCP1 protein expression in WAT of HIIT group (p&gt;.05). 4. Compared with group C, the expression of NPY mRNA in hypothalamus in group MD was significantly decreased,(p&lt;.01), POMC, LEPR, GRP78 mRNA expression had no significant difference (p&gt;.05); Compared with group C, there was no significant difference in the expression of hypothalamus POMC, NPY，LEPR and GRP78 mRNA in HIIT group (p&gt;.05). 5. There was a negative correlation between the expression of NPYmRNA in hypothalamus and the expression of PRDM16 protein in white fat(p&lt;.01).&#x0D; Conclusions Moderate-intensity exercise for 4 weeks in the growth and development period of rats can decrease NPY expression in hypothalamus of rats and induce white-to-brown phenomena in perirenal adipose tissue ,but not in HIIT.

Short-Term High- and Moderate-Intensity Training Modifies Inflammatory and Metabolic Factors in Response to Acute Exercise.

Purpose: To compare the acute and chronic effects of high intensity intermittent training (HIIT) and steady state training (SST) on the metabolic profile and inflammatory response in physically active men.Methods: Thirty recreationally active men were randomly allocated to a control group (n = 10), HIIT group (n = 10), or SST group (n = 10). For 5 weeks, three times per week, subjects performed HIIT (5 km 1-min at 100% of maximal aerobic speed interspersed by 1-min passive recovery) or SST (5 km at 70% of maximal aerobic speed) while the control group did not perform training. Blood samples were collected at fasting (~12 h), pre-exercise, immediately post, and 60 min post-acute exercise session (pre- and post-5 weeks training). Blood samples were analyzed for glucose, non-ester fatty acid (NEFA), and cytokine (IL-6, IL-10, and TNF-α) levels through a three-way analysis (group, period, and moment of measurement) with repeated measures in the second and third factors.Results: The results showed an effect of moment of measurement (acute session) with greater values to TNF-α and glucose immediately post the exercise when compared to pre exercise session, independently of group or training period. For IL-6 there was an interaction effect for group and moment of measurement (acute session) the increase occurred immediately post-exercise session and post-60 min in the HIIT group while in the SST the increase was observed only 60 min post, independently of training period. For IL-10, there was an interaction for training period (pre- and post-training) and moment of measurement (acute session), in which in pre-training, pre-exercise values were lower than immediately and 60 min post-exercise, in post-training period pre-exercise values were lower than immediately post-exercise and immediately post-exercise lower than 60 min post, it was also observed that values immediately post-exercise were lower pre- than post-training, being all results independently of intensity (group).Conclusion: Our main result point to an interaction (acute and chronic) for IL-10 showing attenuation post-training period independent of exercise intensity.

Can short-term high-intensity intermittent training reduce adiposity?

To compare the effects of 6 weeks of high-intensity intermittent training (HIIT) and moderate intensity continuous exercise (MICT-control group) on body composition, hunger and food intake. Twenty-three previously untrained women (28.43 ± 12.53 years) were randomly assigned to a HIIT (n = 11) or MICT group (n = 12). The HIIT group performed 15 1-min bouts at 90 % of maximum heart rate (HRmax) interspersed by 30-s active recovery (60 % HRmax). The MICT group performed a continuous exercise at 70 % HRmax equalizing the training load method proposed by Edwards (1993) to a similar value achieved by the HIIT group. Training for both groups was performed three times per week for 6 weeks. All subjects performed the Astrand cycloergometer test to estimate maximal oxygen consumption (VO2max) 1 week before and after the training period, as well as body composition, which was estimated through circumferences and skinfold thicknesses. For all training sessions heart rate, visual scale of hunger and internal load were recorded. In the first and last week of training subjects were asked to record a 24-h food diary for 3 days. Both training induced significant pre- to post-decreases for fat mass, fat percentage, waist circumference and sum of seven skinfolds. However, only the sum of skinfolds differed between protocols with a higher mean percentage change for HIIT compared to the MICT. As expected, estimated VO2max increased in both groups. There were no differences for hunger, energy intake and body mass. HIIT resulted in a greater fat loss compared to moderate continuous aerobic training.

Small-Sided Games Versus Interval Training in Amateur Soccer Players

The purpose of this study was to compare the effects of small-sided games (SSGs) in soccer versus high-intensity intermittent training (HIT) on a continuous aerobic test (Vameval) and the performance in an intermittent test with changes of direction (CODs; 30-15 intermittent fitness test [30-15(IFT)]). Twenty-two amateur soccer players (mean age ± SD: 26.3 ± 4.7 years) were assigned to 3 different groups for 6 weeks: SSG group (n = 8), HIT group (n = 8), and control group (CG; n = 6). In addition to the usual technical and tactical sessions and competitive games, the SSG group performed 9 sessions of 2 versus 2 and 1 versus 1 SSGs, whereas the HIT group performed 9 sessions of intermittent runs in the form of 30 seconds of effort interspersed with 30 seconds of passive recovery (30s-30s), 15s-15s, and 10s-10s. The HIT and SSG groups showed performance improvements in the Vameval test (5.1 and 6.6%, respectively) and the 30-15(IFT) intermittent test with CODs (5.1 and 5.8%, respectively), whereas there was no change in the performance of the CG. Players from HIT and SSG groups showed similar increase in their performance in the 30-15(IFT) and the Vameval tests during the 6-week training period, especially with an increase significantly different to that in a traditional training as in the CG (p < 0.05). This investigation demonstrates that both SSG and HIT interventions are equally effective in developing the aerobic capacity and the ability to perform intermittent exercises with CODs in male amateur soccer players. Furthermore, these 2 methods of training applied during the 6 weeks induce similar effect on the recovery capacity and on the ability to repeat directional changes of 180°. Coaches will now be able to choose between these two methods according to the objective of the training and to optimize the training.

Effects of high-intensity intermittent training on carnitine palmitoyl transferase activity in the gastrocnemius muscle of rats.

We examined the capacity of high-intensity intermittent training (HI-IT) to facilitate the delivery of lipids to enzymes responsible for oxidation, a task performed by the carnitine palmitoyl transferase (CPT) system in the rat gastrocnemius muscle. Male adult Wistar rats (160-250 g) were randomly distributed into 3 groups: sedentary (Sed, N = 5), HI-IT (N = 10), and moderate-intensity continuous training (MI-CT, N = 10). The trained groups were exercised for 8 weeks with a 10% (HI-IT) and a 5% (MI-CT) overload. The HI-IT group presented 11.8% decreased weight gain compared to the Sed group. The maximal activities of CPT-I, CPT-II, and citrate synthase were all increased in the HI-IT group compared to the Sed group (P < 0.01), as also was gene expression, measured by RT-PCR, of fatty acid binding protein (FABP; P < 0.01) and lipoprotein lipase (LPL; P < 0.05). Lactate dehydrogenase also presented a higher maximal activity (nmol·min−1·mg protein−1) in HI-IT (around 83%). We suggest that 8 weeks of HI-IT enhance mitochondrial lipid transport capacity thus facilitating the oxidation process in the gastrocnemius muscle. This adaptation may also be associated with the decrease in weight gain observed in the animals and was concomitant to a higher gene expression of both FABP and LPL in HI-IT, suggesting that intermittent exercise is a “time-efficient” strategy inducing metabolic adaptation.