Work Rate and Oxygen Uptake
The Relationship Between Work Rate And Oxygen Uptake During Incremental Submaximal Exercise
Introduction
Oxygen uptake () describes the rate at which oxygen is utilized by tissues (Burton et al, 2004). is determined by heart rate (heart beats each minute), stroke volume (the volume of blood pumped from one ventricle each beat) and arteriovenous oxygen difference (difference in blood-oxygen content between arterial and venous blood). Oxygen is needed for respiration, the chemical process that produces energy in the form of ATP. Several sources agree that oxygen uptake increases linearly with exercise, this is due to the skeletal muscles requirement for more oxygen for the production of more ATP. Hanson et al (1998) measured continuously in 10 healthy participants during cycling exercise while varying the rate of work incrementation, they found oxygen uptake to increase linearly at low intensities but to a greater asymptote at higher intensities. The aim of this study was to analyze the effect of incremental submaximal exercise on and therefore determine whether there is a correlation between oxygen uptake and work rate.
Method
The saddle height of the Monark peak 894 ergometer was adjusted according to the participant (Gender: Male, Age: 21), they were asked to breathe into the gas collection apparatus wearing a nose-clip in order to re-establish normal breathing during the trial. The participant was then asked to cycle for 16 minutes at 4 progressively higher exercise intensities, starting with 1.5kg and going up in 0.5kg increments, cycling continuously at 60 rpm throughout. Each interval lasted 4 minutes; in the last minute of each interval a one-minute sample of air was collected into one of the four prepared Douglas bags. In addition, a rating of perceived excursion (RPE) was recorded by communicating an RPE chart in the final minute. Heart rate of the participant was recorded in 15s intervals. At each increment, 0.5kg was applied to the flywheel
Introduction
Oxygen uptake () describes the rate at which oxygen is utilized by tissues (Burton et al, 2004). is determined by heart rate (heart beats each minute), stroke volume (the volume of blood pumped from one ventricle each beat) and arteriovenous oxygen difference (difference in blood-oxygen content between arterial and venous blood). Oxygen is needed for respiration, the chemical process that produces energy in the form of ATP. Several sources agree that oxygen uptake increases linearly with exercise, this is due to the skeletal muscles requirement for more oxygen for the production of more ATP. Hanson et al (1998) measured continuously in 10 healthy participants during cycling exercise while varying the rate of work incrementation, they found oxygen uptake to increase linearly at low intensities but to a greater asymptote at higher intensities. The aim of this study was to analyze the effect of incremental submaximal exercise on and therefore determine whether there is a correlation between oxygen uptake and work rate.
Method
The saddle height of the Monark peak 894 ergometer was adjusted according to the participant (Gender: Male, Age: 21), they were asked to breathe into the gas collection apparatus wearing a nose-clip in order to re-establish normal breathing during the trial. The participant was then asked to cycle for 16 minutes at 4 progressively higher exercise intensities, starting with 1.5kg and going up in 0.5kg increments, cycling continuously at 60 rpm throughout. Each interval lasted 4 minutes; in the last minute of each interval a one-minute sample of air was collected into one of the four prepared Douglas bags. In addition, a rating of perceived excursion (RPE) was recorded by communicating an RPE chart in the final minute. Heart rate of the participant was recorded in 15s intervals. At each increment, 0.5kg was applied to the flywheel
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