Blood metabolite data in response to maximal exercise in healthy subjects.
Maximal exercise test with gas exchange measurement evaluates exercise capacities with maximal oxygen uptake (VO(2) max) measurement. Measurements of lactate (L), lactate/pyruvate ratio (L/P) and ammonium (A) during rest, exercise and recovery enhance interpretative power of maximal exercise by incorporating muscular metabolism exploration. Maximal exercise test with gas exchange measurement is standardized in cardiopulmonary evaluations but, no reference data of blood muscular metabolites are available to evaluate the muscular metabolism. We determined normal values of L, L/P and A during a standardized maximal exercise and recovery in 48 healthy sedentary volunteers and compared with results obtained in four patients with exercise intolerance and a mitochondrial disease. In healthy subjects, L, L/P and A rose during exercise. In 98% of them L, L/P or A decreased between the fifth and the fifteenth minutes of recovery. In mitochondrial patients, VO(2) max was normal or low, and L, L/P and A had the same evolution as normal subjects or showed no decrease during recovery. We gave normal L, L/P and A values, which establish references for a maximal exercise test with muscular metabolism exploration. This test is helpful for clinicians in functional evaluation, management and treatment of metabolic myopathy and would be a useful tool in diagnosis of metabolic myopathy.
Department of Physiology, CHU de Caen, Caen, France. mouadil-a@chu-caen.fr
Amèle
A
Mouadil
Claire
C
Debout
Marie-Hélène
MH
Read
Rémy
R
Morello
Stéphane
S
Allouche
Françoise
F
Chapon
D000328:Adult; D000641:Ammonia / Q000097:blood; D015415:Biomarkers / Q000097:blood; D004734:Energy Metabolism; D015444:Exercise; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D005602:France; D006339:Heart Rate; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008875:Middle Aged; D028361:Mitochondrial Diseases / Q000097:blood / Q000503:physiopathology; D009119:Muscle Contraction; D018482:Muscle, Skeletal / Q000378:metabolism* / Q000503:physiopathology; D009135:Muscular Diseases / Q000097:blood / Q000503:physiopathology; D010101:Oxygen Consumption; D019289:Pyruvic Acid / Q000378:metabolism; D020127:Recovery of Function; D013997:Time Factors
D015415:Biomarkers; D019344:Lactic Acid; D000641:Ammonia; D019289:Pyruvic Acid