Difference in Central Fatigue During Two Ultra-endurance Practices: Running vs. Cycling

Study Overview
=================
Brief Summary
-----------------
The mechanisms contributing to muscle fatigue in extreme long-duration exercise bouts are poorly understood. Ultra-endurance exercise is an excellent model for the study of adaptive responses to extreme loads and stress and it is an especially useful model for documenting the origins of central fatigue. This protocol will compare fatigue during and after ultra-endurance exercise bouts that result in moderate lower-limb tissue damage (i.e. cycling) or significant damage (i.e. running). The results of this protocol will allow us to further understanding of the reasons for major central fatigue, i.e. within the central nervous system, in ultra-endurance.

Official Title
-----------------
Difference in Central Fatigue During Two Ultra-endurance Practices: Running vs. Cycling

Conditions
-----------------
Ultra-marathon Runners

Intervention / Treatment
-----------------
* Other: maximum effort test on a cycloergometer
* Other: maximum effort test on a treadmill


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Specialist in endurance and ultra-endurance. in the 2 disciplines: running and cycling (triathletes, duathletes or trailers achieving at least 30% of their training volume in cycling), and having at least finished one long distance event in the last 2 years, Affiliated or beneficiary of a social security scheme. Signature of the consent form Exclusion Criteria: Any subject who has been injured in the 3 months prior to the protocol Anyone with chronic joint pathologies (e.g.: repetitive sprains, patellar or ligament problems). Any subject with chronic or central neurological pathologies Any subject with a contraindication to magnetic stimulation Use of neuro-active substances likely to alter cortico-spinal excitability (hypnotics, antiepileptics, psychotropic drugs, muscle relaxants) on the study. Contraindication to the application of a magnetic field: Heart or respiratory insufficiency. Subject with a cardiac pace maker. Cardiac valve wear and serious cardiovascular diseases. Presence of prosthetic material or ferromagnetic foreign bodies in the head. Presence of cochlear implants or ocular prosthetic material. History of neurosurgical interventions. Neurological diseases that may affect brain structures and cognitive abilities (e.g., intracranial tumour, multiple sclerosis, history of stroke or traumatic brain injury). History of comitiality, contralateral knee disease or musculoskeletal disease. Any subject participating at the same time in another interventional experiment requiring physical exercise. Any subject who has taken corticosteroids within 3 months (inhalation, infiltration or history of prolonged corticosteroid therapy). Any subject under guardianship or curatorship

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
Male

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Prospective study of physiopathology on subjects specializing in endurance and ultra-endurance: comparing running vs. cycling. Cross-over: each subject will carry out the 2 experimental conditions (running and cycling) according to a randomized order of passage, respecting a wash-out of 2 weeks.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Running endurance<br>Athletes wiil run for 5 hours in a row. | Other: maximum effort test on a treadmill<br>* 5 h test on treadmill<br>|
| Experimental: Cycling endurance<br>Athletes wiil cycle for 5 hours in a row. | Other: maximum effort test on a cycloergometer<br>* 5 h test on cycloergometer<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum level of voluntary activation of relative central fatigue | measured in isometric mode of the knee extensors, between the value before and immediately after a 5-hour cycling or running event at the same relative intensity | Before and immediately after 5h exercise | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Maximum level of voluntary activation of fatigue centrale absolute | measured in isometric mode of the knee extensors, between the value before the 5h cycling or running and the value after absolute exhaustion | Before and immediately after 5h exercise | 
| Maximum level of voluntary activation with electrical evoked activation | tests with measurement of the maximum voluntary with evoked electrical between the value before and immediately after a 5-hour cycling or running event at the same relative intensity | Before and immediately after 5h exercise | 
| Spinal excitability | thoracic spine stimulation for the recording of thoracic motor evoked potentials | Before and immediately after 5h exercise | 
| Corticospinal excitability | stimulation of the motor cortex for recording motor evoked potentials | Before and immediately after 5h exercise | 
| Cortical excitability | ratio between stimulation of the motor cortex and thoracic spine stimulation | Before and immediately after 5h exercise | 
| Measurement of isometric force values | subjects sitting on a Cybex type seat, with the knee and hip angle set at 90°. The foot will be attached to a strain-gauge sensor using a velcro strap attached to the ankle above the medial malleolus. | Before and immediately after 5h exercise | 
| Measurement of speed, force and power values | assessment of fatigue in dynamic mode (calculation of the force/speed profile) | Before and immediately after 5h exercise | 
| Red blood cells | blood sample | Before and immediately after 5h exercise | 
| Platelets | blood sample | Before and immediately after 5h exercise | 
| White blood cells | blood sample | Before and immediately after 5h exercise | 
| Hemoglobin | blood sample | Before and immediately after 5h exercise | 
| Mean corpuscular hemoglobin concentration | blood sample | Before and immediately after 5h exercise | 
| C-reactive protein | blood sample | Before and immediately after 5h exercise | 
| Creatine PhosphoKinase | blood sample | Before and immediately after 5h exercise | 
| Interleukines | blood sample | Before and immediately after 5h exercise | 
| Lactate | blood sample | Before and immediately after 5h exercise | 
| Measurement of the time maintained at the speed corresponding to the 2nd ventilatory threshold | On treadmill | Before and immediately after 5h exercise | 
| measurement of the time maintained at the power corresponding to the 2nd ventilatory threshold | On Cycloergometer | Before and immediately after 5h exercise | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
central fatigue, peripheral fatigue, ultra-endurance exercise, corticospinal excitability