Ultra-marathon Runners
Conditions
Keywords
central fatigue, peripheral fatigue, ultra-endurance exercise, corticospinal excitability
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.
Interventions
OTHERmaximum effort test on a cycloergometer
5 h test on cycloergometer
OTHERmaximum effort test on a treadmill
5 h test on treadmill
Sponsors
Centre Hospitalier Universitaire de Saint Etienne
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention 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.
Eligibility
Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
Yes
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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Maximum level of voluntary activation of relative central fatigue | Before and immediately after 5h exercise | 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 |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Maximum level of voluntary activation of fatigue centrale absolute | Before and immediately after 5h exercise | measured in isometric mode of the knee extensors, between the value before the 5h cycling or running and the value after absolute exhaustion |
| Maximum level of voluntary activation with electrical evoked activation | Before and immediately after 5h exercise | 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 |
| Spinal excitability | Before and immediately after 5h exercise | thoracic spine stimulation for the recording of thoracic motor evoked potentials |
| Corticospinal excitability | Before and immediately after 5h exercise | stimulation of the motor cortex for recording motor evoked potentials |
| Cortical excitability | Before and immediately after 5h exercise | ratio between stimulation of the motor cortex and thoracic spine stimulation |
| Measurement of isometric force values | Before and immediately after 5h exercise | 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. |
| Measurement of speed, force and power values | Before and immediately after 5h exercise | assessment of fatigue in dynamic mode (calculation of the force/speed profile) |
| Red blood cells | Before and immediately after 5h exercise | blood sample |
| Measurement of the time maintained at the speed corresponding to the 2nd ventilatory threshold | Before and immediately after 5h exercise | On treadmill |
| White blood cells | Before and immediately after 5h exercise | blood sample |
| Hemoglobin | Before and immediately after 5h exercise | blood sample |
| Mean corpuscular hemoglobin concentration | Before and immediately after 5h exercise | blood sample |
| C-reactive protein | Before and immediately after 5h exercise | blood sample |
| Creatine PhosphoKinase | Before and immediately after 5h exercise | blood sample |
| Interleukines | Before and immediately after 5h exercise | blood sample |
| Lactate | Before and immediately after 5h exercise | blood sample |
| measurement of the time maintained at the power corresponding to the 2nd ventilatory threshold | Before and immediately after 5h exercise | On Cycloergometer |
| Platelets | Before and immediately after 5h exercise | blood sample |
Countries
France
Outcome results
None listed