Cardiac output and performance during a marathon race in middle-aged recreational runners
Abstract
Purpose. Despite the increasing popularity of marathon running, there are no data on the responses of stroke volume (SV) and cardiac output (CO) to exercise in this context. We sought to establish whether marathon performance is associated with the ability to sustain high fractional use of maximal SV and CO (i.e, cardiac endurance) and/or CO, per meter (i.e., cardiac cost). Methods. We measured the SV, heart rate (HR), CO, and running speed of 14 recreational runners in an incremental, maximal laboratory test and then during a real marathon race (mean performance 3hr 30min ± 45min). Results. Our data revealed that HR, SV and CO were all in a high but submaximal steady state during the marathon (87.0 ± 1.6, 77.2 ± 2.6, and 68.7 ± 2.8 of maximal values, respectively). Marathon performance was inversely correlated with an upward drift in the CO/speed ratio (mL of CO m -1) (r=-0.65, P<0.01) and positively correlated with the runner's ability to complete the race at a high percentage of the speed at maximal SV (r=0.83, P<0.0002). Conclusion. Our results showed that marathon performance is inversely correlated with cardiac cost and positively correlated with cardiac endurance. The CO response could be a benchmark for race performance in recreational marathon runners. Copyright © 2012 Véronique L. Billat et al.
Keywords
article
heart output
heart performance
heart stroke volume
human
marathon runner
normal human
steady state
velocity
endurance
metabolism
methodology
physiology
Adult
Anthropometry
Cardiac Output
Electromyography
Exercise
Heart Rate
Humans
Male
Middle Aged
Oxygen
Oxygen Consumption
Physical Endurance
Running