Biomaterial Database

The ventilation, lactate and electromyographic thresholds during incremental exercise tests in normoxia, hypoxia and hyperoxia. 1994

J H Mateika, and J Duffin

Department of Anesthesia, University of Toronto, Ontario, Canada.

These experiments examined the effect of hypoxia and hyperoxia on ventilation, lactate concentration and electromyographic activity during an incremental exercise test in order to determine if coincident chances in ventilation and electromyographic activity occur during an incremental exercise test, despite an enhancement or reduction of peripheral chemoreceptor activity. In addition, these experiments were completed to determine if electromyographic activity and ventilation are enhanced or reduced in response to the inspiration of oxygen-depleted and oxygen-enriched air, respectively. Seven subjects performed three incremental exercise tests, until volitional exhaustion was achieved, while inspiring air with a fractional concentration of oxygen of either 66%, 21% or 17%. In addition, another single subject completed two tests while inspiring air with a fractional concentration of either 17% or 21%. During the tests, ventilation, mixed expired oxygen and carbon dioxide, arterialized venous blood and the electromyographic activity from the vastus lateralis were sampled. From these values ventilation, electromyographic and lactate thresholds were detected during normoxia, hypoxia and hyperoxia. The results showed that although ventilation and lactate concentration were significantly less during hyperoxia as compared to normoxia or hypoxia, the carbon dioxide production values were not significantly different between the normoxic, hypoxic and hyperoxic conditions. For a particular condition, the time, carbon dioxide production and oxygen consumption values that corresponded to the ventilation and electromyographic thresholds were not significantly different, but the values corresponding to the lactate threshold were significantly less than those for the electromyographic and ventilation thresholds. Comparisons between the three conditions showed that the time, carbon dioxide production and oxygen consumption values corresponding to each of these thresholds were not significantly difficult.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
D007773	Lactates	Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
D008297	Male		Males
D009584	Nitrogen	An element with the atomic symbol N, atomic number 7, and atomic weight [14.00643; 14.00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth's atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells.
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
D012119	Respiration	The act of breathing with the LUNGS, consisting of INHALATION, or the taking into the lungs of the ambient air, and of EXHALATION, or the expelling of the modified air which contains more CARBON DIOXIDE than the air taken in (Blakiston's Gould Medical Dictionary, 4th ed.). This does not include tissue respiration (	Breathing
D001784	Blood Gas Analysis	Measurement of oxygen and carbon dioxide in the blood.	Analysis, Blood Gas,Analyses, Blood Gas,Blood Gas Analyses,Gas Analyses, Blood,Gas Analysis, Blood
D002245	Carbon Dioxide	A colorless, odorless gas that can be formed by the body and is necessary for the respiration cycle of plants and animals.	Carbonic Anhydride,Anhydride, Carbonic,Dioxide, Carbon
D002628	Chemoreceptor Cells	Cells specialized to detect chemical substances and relay that information centrally in the nervous system. Chemoreceptor cells may monitor external stimuli, as in TASTE and OLFACTION, or internal stimuli, such as the concentrations of OXYGEN and CARBON DIOXIDE in the blood.	Chemoreceptive Cells,Cell, Chemoreceptive,Cell, Chemoreceptor,Cells, Chemoreceptive,Cells, Chemoreceptor,Chemoreceptive Cell,Chemoreceptor Cell
D004576	Electromyography	Recording of the changes in electric potential of muscle by means of surface or needle electrodes.	Electromyogram,Surface Electromyography,Electromyograms,Electromyographies,Electromyographies, Surface,Electromyography, Surface,Surface Electromyographies
D005080	Exercise Test	Controlled physical activity which is performed in order to allow assessment of physiological functions, particularly cardiovascular and pulmonary, but also aerobic capacity. Maximal (most intense) exercise is usually required but submaximal exercise is also used.	Arm Ergometry Test,Bicycle Ergometry Test,Cardiopulmonary Exercise Testing,Exercise Testing,Step Test,Stress Test,Treadmill Test,Cardiopulmonary Exercise Test,EuroFit Tests,Eurofit Test Battery,European Fitness Testing Battery,Fitness Testing,Physical Fitness Testing,Arm Ergometry Tests,Bicycle Ergometry Tests,Cardiopulmonary Exercise Tests,Ergometry Test, Arm,Ergometry Test, Bicycle,Ergometry Tests, Arm,Ergometry Tests, Bicycle,EuroFit Test,Eurofit Test Batteries,Exercise Test, Cardiopulmonary,Exercise Testing, Cardiopulmonary,Exercise Tests,Exercise Tests, Cardiopulmonary,Fitness Testing, Physical,Fitness Testings,Step Tests,Stress Tests,Test Battery, Eurofit,Test, Arm Ergometry,Test, Bicycle Ergometry,Test, Cardiopulmonary Exercise,Test, EuroFit,Test, Exercise,Test, Step,Test, Stress,Test, Treadmill,Testing, Cardiopulmonary Exercise,Testing, Exercise,Testing, Fitness,Testing, Physical Fitness,Tests, Arm Ergometry,Tests, Bicycle Ergometry,Tests, Cardiopulmonary Exercise,Tests, EuroFit,Tests, Exercise,Tests, Step,Tests, Stress,Tests, Treadmill,Treadmill Tests