High-intensity Interval Training Prescription Research Articles

Effect of different forms of high-intensity interval training on V̇O2max, strength, flexibility, and body fat percentage among middle-aged males.

High-intensity interval training (HIIT) has become a popular exercise approach due to its potential to elicit significant physiological adaptations. However, limited research has compared the effects of different HIIT modalities on fitness parameters in middle-aged males. This study aimed to determine the effect of different HIIT on V̇O<inf>2max</inf>, strength, flexibility, and body fat percentage among middle-aged males. Thirty sedentary males aged 40-50 years were randomly assigned to HIIT-Weight Training Circuit (WTC), HIIT-Shuttle Run (SR), or HIIT-Bodyweight Exercise (BWE) groups. Training consisted of 20 sessions over 5 weeks of 4×4 minutes at 90-95% HR<inf>max</inf> with 3 minutes recovery at 70% HR<inf>max</inf> between intervals. Outcome measures including V̇O<inf>2max</inf>, strength, flexibility, and body fat percentage were assessed pre- and postintervention. The result for the Two-Way Mixed ANOVA indicated there was no significant interaction effect between the three training groups. There was no significant main effect for the three training groups, whereas there was a significant effect for the repeated measure time existed. A significant improvement in V̇O<inf>2max</inf>, strength, flexibility has been shown between post-test and pre-test for the HIIT-SR, HIIT-WTC, and HIIT-BWE group. Whereas A significant decrease has been shown between post and pretest for all the groups in body fat percentage. This research findings suggested that different forms of HIIT can elicit differential adaptation in middle-aged males. Incorporating different form of HIIT as HITT-SR, HITT-WTC, and HITT-BWE into exercise program may be an effective way to systematically improve V̇O<inf>2max</inf>, strength, flexibility, and body composition in middle-age male population. These findings provide guidance on HIIT prescription according to fitness goals.

It's about the long game, not epic workouts: unpacking HIIT for endurance athletes.

High-intensity interval training (HIIT) prescriptions manipulate intensity, duration, and recovery variables in multiple combinations. Researchers often compare different HIIT variable combinations and treat HIIT prescription as a "maximization problem", seeking to identify the prescription(s) that induce the largest acute VO2/HR/RPE response. However, studies connecting the magnitude of specific acute HIIT response variables like work time>90% of VO2max and resulting cellular signalling and/or translation to protein upregulation and performance enhancement are lacking. This is also not how successful endurance athletes train. First, HIIT training cannot be seen in isolation. Successful endurance athletes perform most of their training volume below the first lactate turn point (<LT1), with "threshold training" and HIIT as integrated parts of a synergistic combination of training intensities and durations. Second, molecular signalling research reveals multiple, "overlapping" signalling pathways driving peripheral adaptations, with those pathways most sensitive to work intensity showing substantial feedback inhibition. This makes current training content and longer-term training history critical modulators of HIIT adaptive responses. Third, long term maximization of endurance capacity extends over years. Successful endurance athletes balance low-intensity and high-intensity, low systemic stress, and high systemic stress training sessions over time. The endurance training process is therefore an "optimization problem". Effective HIIT sessions generate both cellular signal and systemic stress that each individual athlete responds to and recovers from over weeks, months, and even years of training. It is not "epic" HIIT sessions but effective integration of intensity, duration, and frequency of all training stimuli over time that drives endurance performance success.

High-Intensity Interval Training Prescription for Combat-Sport Athletes.

Combat sports are composed of high-intensity actions (eg,attacks, defensive actions, and counterattacks in both grappling and striking situations depending on the specific sport) interspersed with low-intensity actions (eg,displacement without contact, stepping) or pauses (eg,referee stoppages), characterizing an intermittent activity. Therefore, high-intensity interval training (HIIT) is at the essence of combat-sport-specific training and is used as complementary training, as well. HIIT prescription can be improved by using intensity parameters derived from combat-sport-specific tests. Specifically, the assessment of physiological indexes (intensity associated with the maximal blood lactate steady state, maximal oxygen consumption, and maximal sprint) or of time-motion variables (high-intensity actions, low-intensity actions, and effort:pause ratio) is a key element for a better HIIT prescription because these parameters provide an individualization of the training loads imposed on these athletes. To present a proposal for HIIT prescription for combat-sport athletes, exemplifying with different HIIT protocols (HIIT short intervals, HIIT long intervals, repeated-sprint training, and sprint interval training) using combat-sport-specific actions and the parameters for the individualization of these protocols. The use of combat-sport-specific tests is likely to improve HIIT prescription, allowing coaches and strength and conditioning professionals to elaborate HIIT short intervals, HIIT long intervals, repeated-sprint training, and sprint interval training protocols using combat-sport actions, providing more specificity and individualization for the training sessions.

Does the length used in the 30-15 International Fitness Test (40- vs 28-m) influence the maximal running speed achieved by under-18 players from different sports?

The maximal running speed (MRS) achieved in the 30-15 International Fitness Test (30-15IFT) is widely used to prescribe high-intensity interval training (HIIT). The 30-15IFT can be performed in either 40- (30-15IFT-40) or 28-meters (30-15IFT-28) length. Objectives: The aim of this study was to evaluate the MRS achieved in the 30-15IFT-40 and the 30-15IFT-28. Methods: Fifty U-18 players from different sports (handball: n=19, soccer: n=19, tennis n=12) attended two testing sessions. Results: MRS did not differ between the 30-15IFT-40 and the 30-15IFT-28 in either handball or soccer players. However, tennis players showed significantly greater MRS values in the 30-15IFT-28 than in the 30-15IFT-40 (20.80±1.87 vs 20.05±2.09 km·h-1; p = 0.030; ES = 0.38). In addition, tennis player showed significant greater MRS in the 30-15IFT-28 (20.80±1.87 km·h-1) than both handball (18.58±1.13 km·h-1; p &lt; 0.001; ES = 1.53) and soccer players (18.74±0.93 km·h-1; p = 0.001; ES = 1.47). Conclusions: The different MRS values in the 30-15IFT-40 and the 30-15IFT-28, entail significant practical implications for HIIT prescription in tennis players.

Efectos del entrenamiento por intervalos de alta intensidad sobre capacidad aeróbica en personas con enfermedad de las arterias coronarias

The aim of this review was to know the influence of high-intensity interval training (HIIT) on aerobic capacity in people with coronary artery disease. We conducted a review of systematic reviews and meta-analyzes in PubMed up to 4 June 2019. A total of 23 articles were identified, of which 3 were finally selected for this review. The quality of the included studies was high (AMSTAR-2). The HIIT presented significant improvements in aerobic capacity in this population. The HIIT with duration between 7-12 weeks and intensity higher than 90% HRpeak - 80% VO2peak reported greater improvements in aerobic capacity. Further studies are necessary to establish consistent conclusions about the effects of other elements of HIIT prescription in this population.

PO-220 HIIT prescription and diabetes

Objective To clarify the effect of HIIT prescription on diabetic mellitus (DM) and provide reliable exercise advise for DM patients. Method: Through literature &#x0D; Methods Through literature method to collect studies by key words: HIIT, diabetic mellitus, T1DM , T2DM. And through data analyze method to organize the related studies to make a conclusion.&#x0D; Results As a non-infectious metabolic disease，the incidence of DM is increasingly continuing in recent years. The epidemiological studies show that the global incidence of DM in the population aged 20-79 was 8.8% in 2015, and the total number reached 415 million. It is predicted that by 2040, the number of DM patients in this age group will reach 642 million with the prevalence rate rose to 10.4%. Insulin secretion and insulin signal transduction disorders are the main mechanisms of the onset of type 1 diabetes (T1DM) and type 2 diabetes (T2DM) respectively. The inducers of DM are complex, such as obesity, inactivity, insomnia and heredity. The current interventions for DM are mainly drugs, diet, exercise, self-monitoring and education. Among them, exercise is accepted by the majority of diabetic patients because of its economic, fewer side effects and obvious effects.&#x0D; The occurrence of T1DM is closely related to heredity with the majority of adolescence patients. Due to insufficient insulin secretion, the clinical treatment of T2DM is mainly exogenous insulin injections. However, long-term insulin injections on the one hand leads to a continuous decline in the effect of insulin action, and are also a painful process for T1DM patients. Regular exercise can increase insulin sensitivity, decrease insulin resistance, promote the glucose uptake of skeletal muscle and regulate the blood glucose. However, the occurrence of exercise hypoglycemia makes it difficult for T1DM patients to insist exercise. The mechanism for the occurrence of exercise hypoglycemia is not clear, but studies show that it may related to insulin regulation change, counter-regulatory response decline and energy substrate metabolism disorder. Studies have shown that high intensity interval training (HIIT) prescription can avoid the occurrence of exercise-induced hypoglycemia caused by long-term moderate-intensity exercise to a certain extent. Therefore, the relationship between HIIT exercise and T1DM patients requires more research to prove. The occurrence of T2DM is accompanied by obesity. Obesity leads to the development of insulin resistance. A large number of studies have confirmed that exercise has a good intervention effect on obesity and T2DM. Compared with the traditional moderate intensity continuous training (MICT), HIIT has a better effect on reducing abdominal fat in the obesity. T2DM is often accompanied by many complications, such as diabetes cognitive dysfunction, diabetic Cardiomyopathy, diabetic liver disease and so on. The intervention effect of the HIIT prescription on these complications has also been confirmed by numerous studies.&#x0D; Conclusions As a non-pharmaceutical treatment of diabetes, exercise has obvious effects on diabetes intervention. The HIIT has gradually become one of the exercise intervention prescription because of its short time-consuming and obvious effects. However, the HIIT exercise prescription for DM patients of different ages, types, and complications remains to be further clarified.&#x0D;

The effects of high-intensity interval training on athletic performance measures: a systematic review

Background: Athletic performance consists of attributes including: technique, strength, power, and endurance. There are many training methods designed to optimize athletic performance. High-intensity interval training (HIIT) is one method of athletic performance training that has been found effective in increasing certain physiologic variables such as VO2max. It is unknown if HIIT has positive effects on objective measures of athletic performance.Objective: To systematically review the effects of HIIT on objective, athletic performance measures.Method: A systematic review of literature indexed in the following databases: Medline, CINAHL, SportsDiscus, and PubMed was conducted. The methodological quality of the studies was graded using the PEDro scale.Results: Fourteen studies satisfied the eligibility criteria and were included in this review. Methodological scores based on the PEDro scale were 4/10–7/10. HIIT resulted in improvements in running: 3000 and 5000 m track time (TT), (p = 0.04, p < 0.05, respectively) and 40-m sprint TT (p = 0.091), rowing: 2000-m TT (p = 0.02), cycling increase in 5 mile time trial (p < 0.05), softball significant increase in peak pitch velocity (3%), and hockey skating 33 m sprint (p < 0.05). HIIT training was not significant for swimming endurance trials (p = 0.97). Although HIIT had significant effects on many outcome measures, it was not always more effective than other methods.Conclusion: The findings of this review indicate that HIIT can have beneficial effects on certain athletic performance measures. Although varying HIIT dosages were found effective, there is no clear indication of what HIIT prescription is most effective for specific sports activities.

How Does Interval-Training Prescription Affect Physiological and Perceptual Responses?

The purpose of this study was to compare physiological responses and perceived exertion among well-trained cyclists (n = 63) performing 3 different high-intensity interval-training (HIIT) prescriptions differing in work-bout duration and accumulated duration but all prescribed with maximal session effort. Subjects (male, mean ± SD 38 ± 8 y, VO2peak 62 ± 6 mL · kg-1 · min-1) completed up to 24 HIIT sessions over 12 wk as part of a training-intervention study. Sessions were prescribed as 4 × 16, 4 × 8, or 4 × 4 min with 2-min recovery periods (8 sessions of each prescription, balanced over time). Power output, HR, and RPE were collected during and after each work bout. Session RPE was reported after each session. Blood lactate samples were collected throughout the 12 wk. Physiological and perceptual responses during >1400 training sessions were analyzed. HIIT sessions were performed at 95% ± 5%, 106% ± 5%, and 117% ± 6% of 40-min time-trial power during 4 × 16-, 4 × 8-, and 4 × 4-min sessions, respectively, with peak HR in each work bout averaging 89% ± 2%, 91% ± 2%, and 94% ± 2% HRpeak. Blood lactate concentrations were 4.7 ± 1.6, 9.2 ± 2.4, and 12.7 ± 2.7 mmol/L. Despite the common prescription of maximal session effort, RPE and sRPE increased with decreasing accumulated work duration (AWD), tracking relative HR. Only 8% of 4 × 16-min sessions reached RPE 19-20, vs 61% of 4 × 4-min sessions. The authors conclude that within the HIIT duration range, performing at "maximal session effort" over a reduced AWD is associated with higher perceived exertion both acutely and postexercise. This may have important implications for HIIT prescription choices.

Validity of the 3-Minute All-Out Exercise Test on the CompuTrainer.

The 3-minute all-out exercise test (3MT) has emerged as a useful procedure for identifying critical power (CP) and the finite work capacity above CP (W') within a single visit. The CP concept enables for the prediction of exhaustive time limits (T(LIMs)) for a wide range of severe intensity power outputs and is a method for prescribing high-intensity interval training (HIIT). Road cyclists often use the CompuTrainer for indoor HIIT. The purpose of this study was to validate the 3MT for use on the CompuTrainer. On 4 separate visits, 10 competitive cyclists performed a 3MT, and three separate constant-load bouts projected to yield exhaustive T(LIMs) of 3, 6, and 9 minutes, respectively, using the Computrainer. Actual CP and W' were calculated using the linear work-time (W-t) and power-inverse time (1/t) models. The results for CP (W) from the 3MT (215 ± 40), the W-t model (212 ± 36), and the 1/t model (213 ± 36) did not differ (F = 2.96, p = 0.11, η2(p) = 0.43). Similarly, the results for W' (kJ) for the 3MT (11.2 ± 4.0), the W-t model (12.1 ± 6.5), and the 1/s model (11.7 ± 6.3) did not differ (F = 2.40, p = 0.15, η2(p) = 0.375). We conclude that use of the 3MT and the CP concept for performance assessment and HIIT prescription on the CompuTrainer is a valid procedure.

The impact of high-intensity interval training versus moderate-intensity continuous training on vascular function: a systematic review and meta-analysis.

Vascular dysfunction is a precursor to the atherosclerotic cascade, significantly increasing susceptibility to cardiovascular events such as myocardial infarction or stroke. Previous studies have revealed a strong relationship between vascular function and cardiorespiratory fitness (CRF). Thus, since high-intensity interval training (HIIT) is a potent method of improving CRF, several small randomized trials have investigated the impact on vascular function of HIIT relative to moderate-intensity continuous training (MICT). The aim of this study was to systematically review the evidence and quantify the impact on vascular function of HIIT compared with MICT. Three electronic databases (PubMed, Embase, and MEDLINE) were searched (until May 2014) for randomized trials comparing the effect of at least 2 weeks of HIIT and MICT on vascular function. HIIT protocols involved predominantly aerobic exercise at a high intensity, interspersed with active or passive recovery periods. We performed a meta-analysis to compare the mean difference in the change in vascular function assessed via brachial artery flow-mediated dilation (FMD) from baseline to post-intervention between HIIT and MICT. The impact of HIIT versus MICT on CRF, traditional cardiovascular disease (CVD) risk factors, and biomarkers associated with vascular function (oxidative stress, inflammation, and insulin resistance) was also reviewed across included studies. Seven randomized trials, including 182 patients, met the eligibility criteria and were included in the meta-analysis. A commonly used HIIT prescription was four intervals of 4 min (4 × 4 HIIT) at 85-95% of maximum or peak heart rate (HRmax/peak), interspersed with 3 min of active recovery at 60-70% HRmax/peak, three times per week for 12-16 weeks. Brachial artery FMD improved by 4.31 and 2.15% following HIIT and MICT, respectively. This resulted in a significant (p < 0.05) mean difference of 2.26%. HIIT also had a greater tendency than MICT to induce positive effects on secondary outcome measures, including CRF, traditional CVD risk factors, oxidative stress, inflammation, and insulin sensitivity. HIIT is more effective at improving brachial artery vascular function than MICT, perhaps due to its tendency to positively influence CRF, traditional CVD risk factors, oxidative stress, inflammation, and insulin sensitivity. However, the variability in the secondary outcome measures, coupled with the small sample sizes in these studies, limits this finding. Nonetheless, this review suggests that 4 × 4 HIIT, three times per week for at least 12 weeks, is a powerful form of exercise to enhance vascular function.

Usefulness of the 6-minute walk test and the 200-metre fast walk test to individualize high intensity interval and continuous exercise training in coronary artery disease patients after acute coronary syndrome: a pilot controlled clinical study

Objective: To study the effects of three individualized exercise training prescriptions using either a percentage of maximal heart rate (HR), maximal 6-minute walk test (6MWT) HR, or maximal 200-metre fast walk test (200-mFWT) HR, on walking performance and exercise capacity in coronary artery disease (CAD) patients. Design: Controlled clinical study. Participants: Twenty-seven outpatients enrolled in a rehabilitation programme after an acute coronary syndrome. Setting: Cardiac rehabilitation unit. Interventions: Three groups: (A): moderate intensity continuous exercise (MICE) at 70% of the maximal HR of the graded maximal exercise test (n = 10); (B): MICE at the maximal 6MWT HR (n = 8); (C): high intensity interval training (HIIT) based on the 6MWT and the 200-mFWT maximal HR (n = 9). Group B and C performed walk tests every 2 weeks, to readjust training HR (THR) if needed. Measures: 6MWT and 200-mFWT performances, peak VO2 and peak power (Pmax). Results: 6MWT and 200-mFWT performances improved significantly and similarly in all groups (P < 0.05). Peak VO2 improved significantly in all groups (P < 0.05), this improvement being higher in group C (HIIT) versus A (P < 0.05). Group B was closer to the recommended THR during exercise sessions compared to group A. Conclusion: This pilot study showed that using the 6MWT and 200-mFWT HR to individualize MICE or HIIT prescription is feasible in CAD patients, and could lead them closer to THR objective, to similar improvements in walking performance, and greater peak VO2 increase for HIIT. Future randomised studies should investigate long-term effects of programmes prescribed from walk tests HR, especially for HIIT modality.

The Impact of Rest Duration on Work Intensity and RPE during Interval Training

To investigate the effect of rest duration on self-selected intensity, physiological responses, and RPE during a standardized, high-intensity interval training prescription. Nine well-trained male runners (VO(2max) 71 +/- 4 mL.kg(-1).min(-1)) performed three treadmill interval training sessions running at constant 5% incline. Six 4-min work bouts with either 1-, 2-, or 4-min recovery periods were performed in each session. Sessions were prescribed as "high-intensity" workouts with the goal being to achieve the highest possible average running speed for the work intervals. Subjects regulated their work and rest intensity based on these instructions. In a fourth interval session, subjects self-selected recovery time in response to a fixed intensity. Running velocity increased slightly (14.7 +/- 0.7 vs 14.4 +/- 0.8 km.h(-1), P = 0.02) when rest increased from 1 to 2 min, but showed no further increase with a 4-min rest (14.7 +/- 0.6 km.h(-1). Work VO(2) was slightly higher with a 2-min rest duration compared with 1 and 4 min (66.2 +/- 4.2 vs 65.1 +/- 4.2 and 64.9 +/- 4.7 mL.kg(-1).min(-1), P < 0.05). Peak blood lactate was similar (6.2 +/- 2.6, 6.8 +/- 2.9, 6.2 +/- 2.6 mmol.L(-1)) across conditions, whereas peak RPE was slightly lower during the 4-min rest condition (17.1 +/- 1.3, 17.7 +/- 1.5, 16.8 +/- 1.5, P < 0.05). With self-selected recovery time and no knowledge of elapsed time, the average rest duration was 118 +/- 23 s. Under self-paced conditions, varying rest duration in a range of 1 to 4 min had limited impact on performance during repeated 4-min high-intensity exercise bouts. Approximately 120 s of active recovery may provide an appropriate balance between intracellular restitution and maintenance of high VO(2) on-kinetics.