HRV-based Training Effects in Athletes

Study Overview
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Brief Summary
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Monitoring individual responses to training is an important key factor to prescribe to most effective training programs. Heart-rate variability (HRV) could be used for monitoring the training status of endurance athletes in order to detect the fatigue status and to assess the adaptation to training. This direct fatigue measuring method has been little used to prescribe or regulate exercise prescription. Moreover, it allows new possibilities for the training load prescription according to an athlete's status, the response to the training load, and the adaptation to training. Regardless HRV-guided training, the athlete performance could also be influenced by precompetitive mood and anxiety, which can also be reflected in the precompetitive HRV scores and the subjective effort perception.

Detailed Description
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Monitoring individual responses to training is an important key factor to prescribe to most effective training programs. A promising variable that is able to reflect positive or negative training adaptation is cardiac autonomic regulation. In general, a decreased training status is associated with a lower power output at the same submaximal heart rate and a slower heart rate recovery, whereas an increased training status is associated with an increased power output, the same submaximal heart rate, and a faster heart rate recovery. In this line, heart-rate variability (HRV), which focuses on the variability of successive R-R intervals, have gained popularity in monitoring the training status of endurance athletes. This tool enables the detection of fatigue status and assesses the adaptation to training. After high intensity training or a short-term overreached period, there is a decrease in the resting HRV values, reflecting the effect of the fatigue. In addition, the increase of the performance after a training period is related to an increase in resting HRV. This direct fatigue measuring method has been little used to prescribe or regulate exercise prescription. Moreover, this HRV-guided training, also called day-to-day periodization, allows new possibilities for the training load prescription according to an athlete's status, the response to the training load, and the adaptation to training. On the other hand, regardless HRV-guided training, the athlete performance could also be influenced by precompetitive mood and anxiety, which can also be reflected in the precompetitive HRV scores and the subjective effort perception. This is another interesting line that pretends to be clarified in this study.

Official Title
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Physiological and Psychological Effects of Heart Rate Variability Based Training in Endurance Athletes

Conditions
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Heart Rate Control, Athlete, Emotions

Intervention / Treatment
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* Other: HRV-based training
* Other: TRAD training


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Belonging to the Spanish Athletics Federation. Training and running in Spanish Athletics Federation contest during at least two years. Stay in the first third of the classification of the previous season last five races. Exclusion Criteria: Cardiovascular pathologies. Parameters of blood pressure (BP) outside of normality. Respiratory problems diagnosed. Be in treatment of psychological problems. Regular consumption of drug (s) with direct or indirect effects on the Nervous System (e.g., anxiolytics, antidepressants, neuroleptics). Consumption of substances not permitted by the International Athletics Federation (IAF). Punctual consumption of medication that could alter the performance due to suffering some disease related to cardiorespiratory system (e.g., influenza). Do not attend at least the 90% of the workouts during the intervention.
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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: HRV-Group<br>Athletes will train according to their basal HRV scores. If the resting HRV is higher tan their basal HRV, they will perform a high or moderate intensity training. If the resting HRV is lower, they will perform a low intensity training. If the resting HRV still lower, they will rest. They will not accumulate two or more days of high-moderate intensity training, nor two or more days of rest. | Other: HRV-based training<br>* Intervention based on HRV-guided training for the performance improvement of athletes. Pre-competitive HRV, subjective effort perception, anxiety and mood will also be analysed.<br>|
| Active Comparator: TRAD-Group<br>Athletes will train according to their trainer plan. Training will not be guided by their basal HRV scores. | Other: TRAD training<br>* Traditional endurance training<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| VO2max | Maximal oxygen consumption in treadmill test | Change from baseline VO2max at 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| maximal heart rate | maximal heart rate in the treadmill test | Change from baseline maximal heart rate at 8 weeks | 
| maximal speed | maximal speed in the treadmill test | Change from baseline maximal speed at 8 weeks | 
| ventilatory thresolds | ventilatory thresolds in the treadmill test | Change from baseline ventilatory thresolds at 8 weeks | 
| respiratory quotient | respiratory quotient in the treadmill test | Change from baseline respiratory quotient at 8 weeks | 
| Time in running test | Time in the 3000 meters running test | Change from baseline time at 8 weeks | 
| Lactate change | Lactate change after the 3000m test | Change from baseline Lactate at 8 weeks | 
| Speed in running test | Speed in the 3000 meters running test | Change from baseline speed at 8 weeks | 
| Heart rate in running test | Heart rate in the 3000 meters running test | Change from baseline heart rate at 8 weeks | 
| Börg scale after running test | Subjective perceived exertion. Scores goes from 0 to 10. Higher scores indicate a higher perceived exertion. | Through study completion (8 weeks) | 
| LnrMSSD score | Parasympathetic tone and recovery indicator. There are no minimum or maximum values. They depend on the athlete recovery state. Higher scores indicate a better outcome. | Through study completion (8 weeks) | 
| Mood score | Precompetitive mood levels. Instrument: Profile of Mood States. Scores goes from 0 (low mood) to 4 (high mood). | Through study completion (8 weeks) | 
| Anxiety score | Precompetitive anxiety levels. Instrument: Revised Competitive State Anxiety Inventory-2. Scores goes from 1 (no anxiety) to 4 (a lot of anxiety). | Through study completion (8 weeks) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Heart rate variability, Training, Endurance, Mood, Anxiety, Stress, maximal oxygen consumption