Decremental Exercise: a New Training Approach?

Study Overview
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Brief Summary
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Different types of high-intensity interval training (HIIT) sessions are used by athletes in order to improve their physical performance, but innovative approaches to training are lacking. Therefore, in Part A of this study the physiological response to a standard HIIT and a new decremental exercise training (DECT) will be compared in runners and cyclists. Next, in Part B the training effects of a 4-week block of the HIIT and DECT will be compared.

Official Title
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Decremental Exercise Protocol as a Training Stimulus: More or Less Efficient Than Traditional High-intensity Interval Training?

Conditions
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Exercise Performance of Fit Athletes

Intervention / Treatment
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* Other: DECT
* Other: HIIT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age: 18-40 years Healthy, i.e. normal physical and mental status (not taking any medication on a regular basis for more than a month, except contraceptive medication) Normal Body-Mass-Index (BMI): 18.5-24.9 kg·m-2 Well-trained athletes: V̇O2max > 55.1 ml·min-1·kg-1 for men and > 50.1 ml·min-1·kg-1 for women Normal lung function Non-smoking Willing to adhere to the general study rules Exclusion Criteria: Women who are pregnant or breast feeding Intention to become pregnant during the course of the study Known or suspected non-compliance, drug or alcohol abuse Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the participant Previous enrolment into the same part (A or B) of the current study Enrolment of the investigator, his/her family members, employees and other dependent persons Acute or chronic illness Intake of medications affecting performance or the respiratory, cardiovascular or neuromuscular system Insufficient training history (<3 yrs of participation in competitive cycling/running) or training volume (<40 km running/week or 150 km cycling/week) in the previous 6 months Recent (<3 months) history of orthopaedic injury or participation in structured high-intensity training blocks

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: DECT Group<br>The DECT session consists of four bouts of 4 min high-intensity decremental exercise with 3 min of active recovery between bouts. Load is progressively decreased throughout each exercise bout. The training period will last for a total of 4 weeks, with three weekly sessions of supervised training | Other: DECT<br>* The DECT program consists of a 4-week training intervention with three weekly sessions of high-intensity interval training, in which during each exercise bout the workload is imposed in a decremental fashion.<br>|
| Active Comparator: HIIT Group<br>The HIIT session consists of four bouts of 4 min high-intensity decremental exercise with 3 min of active recovery between bouts. Load is kept constant throughout each exercise bout. The training period will last for a total of 4 weeks, with three weekly sessions of supervised training | Other: HIIT<br>* The HIIT program consists of a 4-week training intervention with three weekly sessions of high-intensity interval training, in which during each exercise bout the workload is kept constant.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in exercise performance | Time taken to cover a fixed distance, in minutes | measured before and after the 4-week training block, during a time-trial (40 km cycling or 10 km running) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in maximal oxygen uptake | Measured in ml/kg/min | Measured during a maximal incremental exercise test before and after the 4-week training block | 
| Average oxygen uptake | Average oxygen uptake measured during the four 4-min bouts of high-intensity exercise of a session of HIIT and DECT | The two training session are performed within one week |