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Completed

NCT Number: NCT05067426

The 10/7 HIIT Shock Cycle Study: Effectiveness of 10 HIIT Sessions in 7 Days

A randomized, controlled trial to evaluate the effects of two versions of 10 high intensity interval trainings (HIIT) within a 7-day shock microcycle on endurance performance, well-being, health, stress and recovery in trained athletes.

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Key information

Conditions

Healthy Athlete Performance

Age range

18 year–45 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

University of Salzburg

Salzburg, 5400, Austria

About this study

Thirty-six trained endurance athletes will be recruited and randomly assigned to either a "high volume (HIIT-HV)" group, a "low volume (HIIT-LV)" group, or a control group. All participants will be monitored before (9 days), during (7 days), and after (14 days) a 7-day training intervention, for 30 days. Participants in both intervention groups will complete 10 HIIT sessions within the period of 7 days, with an additional 30 minutes of low-intensity training exclusively in HIIT-HV. HIIT sessions consist of aerobic HIIT, i.e., 5x4min at 90-95% of maximal heart rate interspersed by 2.5 min active recovery periods. To determine the effects of the intervention, performance diagnostics, and a 5 kilometer time trial will be conducted before and after the intervention. In addition, participants are closely monitored for general health, stress, fatigue, recovery, neuromuscular performance, executive functions and sleep.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Female or male
  • aged 18-45 years
  • Proof of physical fitness (e.g. sports medical examination required) for measurements with higher intensities (e.g. endurance tests, competition simulation)
  • Competition experience at the national or international level in an endurance sport
  • VO2max ≥50ml/kg/min for females; ≥55 ml/kg/min for males or a 5-kilometer (km) time trial performance of ≤ 20:00 min (female), or ≤ 18:30 min (male)

Exclusion criteria

  • Systemic disease or other known pathology in the organs: heart, lungs, kidney, stomach, spleen, liver, gall bladder, and intestines.
  • Evidence of pulmonary disease: forced expiratory volume in one second/forced expiratory volume < 70% with/without symptoms (cough, sputum) or other evidence of pulmonologic disease.
  • Diabetes II.
  • Neurological or psychological disease of any kind.
  • Currently undergoing medical or psycho-therapeutic treatment.
  • Health condition that does not allow regular participation in the training forms (e.g. acute illnesses such as fever or other flu-like infections within the last 7 days before the start of the study), orthopedic diseases, injuries to the muscular, bone, joint or tendon apparatus within the last three months.
  • Alcohol or drug abuse.
  • Already high training volume with high intensity training (more than 2 weekly training sessions of high-intensity training)

Treatment and study plan

Exercise

Other

high-intensity interval training sessions

Primary outcomes

  1. Endurance performance I

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of maximal oxygen uptake (VO2max in ml/min/kg) compared to baseline and group

  2. Endurance performance II

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of peak performance (Ppeak in Watt) compared to baseline and group

  3. Endurance performance III

    Time frame: 20 to 22 days (the assessment is conducted once before, and once after the intervention)

    Change of 5 kilometer time trial performance (in sec) compared to baseline and group

  4. Endurance performance IV

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of lactate threshold (in km/h) compared to baseline and group

  5. Endurance performance V

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of ventilatory thresholds (in km/h) compared to baseline and group

  6. Endurance performance VI

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of running economy (in ml/min/kg) compared to baseline and group

Secondary outcomes

  1. Change of questionnaire scores - well-being

    Time frame: 30 days (questionnaires will be given to participants several times before, during, and after the intervention.)

    Change of questionnaire scores compared to baseline and group as determined by a Visual-Analogue-Scale (from 0-100 millimeters). Higher scores indicate poorer well-being.

  2. Change of questionnaire scores - muscular fatigue

    Time frame: 30 days (questionnaires will be given to participants several times before, during, and after the intervention.)

    Change of questionnaire scores compared to baseline and group as determined by a Visual-Analogue-Scale (from 0-100 millimeters). Higher scores indicate higher degree of fatigue.

  3. Change of questionnaire scores - vitality

    Time frame: 30 days (questionnaires will be given to participants several times before, during, and after the intervention.)

    Change of questionnaire scores compared to baseline and group as determined by a Likert-Scale (from 0-10). Higher scores indicate higher vitality.

  4. Change of questionnaire scores - rate of fatigue

    Time frame: 30 days (questionnaires will be given to participants several times before, during, and after the intervention.)

    Change of questionnaire scores compared to baseline and group as determined by a Likert-Scale (from 0-10). Higher scores indicate higher degree of fatigue.

  5. Change of questionnaire scores - sleep quality

    Time frame: 30 days (questionnaires will be given to participants several times before, during, and after the intervention.)

    Change of questionnaire scores compared to baseline and group as determined by a Likert-Scale (from 1-7). Higher scores indicate poorer sleep.

  6. Change of blood count

    Time frame: 30 days (blood is drawn from participants several times before, during, and after the intervention.)

    Change of blood count concentrations compared to baseline and group

  7. Change of cell-free DNA

    Time frame: 30 days (blood is drawn from participants several times before, during, and after the intervention.)

    Change of cell-free DNA concentrations compared to baseline and group

  8. Change of creatine kinase

    Time frame: 30 days (blood is drawn from participants several times before, during, and after the intervention.)

    Change of creatine kinase concentrations compared to baseline and group

  9. Change of urea

    Time frame: 30 days (blood is drawn from participants several times before, during, and after the intervention.)

    Change of urea concentrations compared to baseline and group

  10. Change of blood lactate

    Time frame: 30 days (blood is drawn from participants several times before, during, and after the intervention.)

    Change of blood lactate concentrations compared to baseline and group

  11. Change of cytokines

    Time frame: 30 days (blood is drawn from participants several times before, during, and after the intervention.)

    Change of cytokine concentrations compared to baseline and group

  12. Change of miRNA

    Time frame: 30 days (blood is drawn from participants several times before, during, and after the intervention.)

    Change of miRNA compared to baseline and group

  13. Change of neuromuscular performance

    Time frame: 30 days (neuromuscular performance is assessed several times before, during, and after the intervention)

    Change of neuromuscular performance (counter movement jump height in cm) measured on a contact plate (AMTI, Watertown, USA) compared to baseline and group

  14. Change of body weight

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of body weight in kg compared to baseline and group

  15. Change of fat free mass

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of fat free mass in kg compared to baseline and group

  16. Change of fat mass

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of fat mass in kg compared to baseline and group

  17. Change of forced expiratory volume

    Time frame: 10 to 21 days (assessment is conducted once before the intervention and repeated three times afterwards, i.e. 3, 7 and 14 days after the completion of the intervention)

    Change of forced expiratory volume in liters compared to baseline and group

  18. Change of power output during exercise

    Time frame: 7 days

    Change of power output in Watt (as determined via Stryd, Boulder, USA) during the intervention compared to baseline and group

  19. Change of sleep quality I - GPS watch

    Time frame: 30 days (sleep is assessed several times before, during, and after the intervention)

    Change of sleep quality compared to baseline and group as determined by a GPS (Global Positioning System) watch

  20. Change of sleep quality II - ABIOS App

    Time frame: 30 days (sleep is assessed several times before, during, and after the intervention)

    Change of sleep quality compared to baseline and group as determined by the ABIOS (Algorithmik Biodata System) application

  21. Correlations between sleep quality devices

    Time frame: 30 days

    To determine the correlations between different sleep monitoring devices, i.e. the GPS watch (see outcome 27), the ABIOS system (see outcome 28) and the sleep quality questionnaire (see outcome 11)

  22. Change of parameters recorded by an electrocardiogram - mean heart rate

    Time frame: 30 days (an electrocardiogram is written several times before, during, and after the intervention)

    Change of mean heart rate compared to baseline and group

  23. Change of parameters recorded by an electrocardiogram - heart rate variability

    Time frame: 30 days (an electrocardiogram is written several times before, during, and after the intervention)

    Change of heart rate variability (root mean sum of squared distance in ms) compared to baseline and group

  24. Change of executive functions - Eriksen flanker task

    Time frame: 30 days (executive functions are tested several times before, during, and after the intervention)

    Change of executive functions compared to baseline and group. This is recorded through a modified Eriksen flanker task consisting of 108 images showing five white arrows on a black screen.

  25. Change of executive functions - 2 back task

    Time frame: 30 days (executive functions are tested several times before, during, and after the intervention)

    Change of executive functions compared to baseline and group. This is assessed through a 2-back task showing dots on a dice, numbers and geometrical figures.

  26. Cardiac ultrasound

    Time frame: 1 day (this outcome will be determined once before study start)

    Description of an athlete cohort regarding cardiac chamber volume (in ml, determined via EPIQ CVX, X5-1, Philips Healthcare, Andover, MA, USA)

  27. Adherence to training program

    Time frame: 7 days

    Adherence to the HIIT training programs (determined as the ratio of training sessions performed to prescribed training sessions). This is determined by the researchers by checking the training data of the athletes. For example, if 9 out of 10 sessions were performed, this means 90% adherence.

Sponsors and collaborators

Lead sponsor

University of Salzburg

Other

Collaborators

  • Johannes Gutenberg University Mainz
  • Paracelsus Medical University

Registry information

Official study title

The 10/7 HIIT Shock Cycle Study: The Effects of a 7-Day High-Intensity-Interval Training Shock Microcycle on Endurance Performance, Well-Being, Stress and Recovery in Endurance Trained Athletes - Randomized Controlled Trial

Acronym: THESIS

Important dates

Study start
2021
Primary completion
2022
Study completion
2022
First posted
Oct 5, 2021
Registry last updated
Jan 31, 2024

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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