Skeletal Muscle Blood Flow
Conditions
Keywords
red blood cell, knee extension exercise
Brief summary
Physical exercise triggers various physiological responses including a marked increase in muscle blood flow and oxygen delivery in order to support muscle activity. How muscle blood flow is controlled is currently unclear. The primary purpose of this study is to establish the respective contribution of metabolic (linked to energy requirements) and mechanical (linked to muscle tensions) signals in the exercise hyperemia and the possible role of the red blood cells. Vasodilation and muscle blood flow during exercise are controlled by ATP released in the plasma from the red blood cells in response to a combination of metabolic and mechanical signals applied on the vasculature.
Interventions
OTHERSession 1-4
Familiarization sessions to knee-extensor exercise separated by 72h recovery
OTHERSession 4
After the last familiarization session, 1 maximal incremental test on a bicycle, followed by 72h rest
OTHERSession 5
2 maximal incremental tests of knee-extension exercise (concentric vs eccentric), separated by 3h rest.
Sponsors
University Hospital, Strasbourg, France
Study design
Observational model
CASE_ONLY
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
MALE
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
* Non smoker or having stopped smoking for at least 5 yr * Practice sports: physical activity level will be evaluated with a questionnaire (de Baecke et coll., 1982) and will give an activity index greater than 6 together with a VO2max greater than 50 ml/kg/min * Body mass index lower than 25 * Registered to the French Social Security system * Providing a written and informed consent to participate in the study
Exclusion criteria
* History of venous or arterial thrombo-embolic events * Bad perfusion from the cubital artery * Unable to understand the information notice * Subject exposed to law investigations or with financial dependancy * Subjects feeling unwell whan seing blood. * Subjects advised to not practice sport. * Musculo-tendinous or articular issues with the lower leg * Respiratory, cardiovascular or metabolic pathologies * Current medical treatment that can not be stopped 7 days before the experiment.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in leg blood flow during concentric and eccentric muscle work | Leg blood flow measurements during exercises performed at the beginning, after 14 minutes, then after 18 min, 22 min, 26 min, 30 min, 33 min, 35 min and 45 min | Serial measures (9) of leg blood flow during concentric and eccentric muscle work are performed at the beginning of the exercise (t0), and then after 14 minutes (t14), after 18 minutes (t18), after 22 minutes (t22), after 26 minutes (t26), after 30 minutes (t30), after 33 minutes (t33), after 35 minutes (t35), and after 45 minutes (45) during each exercice, concentric and eccentric. |
Countries
France
Outcome results
None listed