Corey Hazekamp, Nick Hopper, Rob Gonzalez


CU Boulder Fall 2008


Does a poor circulatory system have an effect on brain function? We wanted to determine whether a more effective circulatory system would improve brain reaction time. Specifically, we were trying to figure out whether or not improved physical health, which should reflect a more effective circulatory system, will improve a personÕs brain function.


We tested the hypothesis that greater aerobic fitness leads to faster reaction times. We reasoned that people with a faster recovery rate would have a quicker reaction time due to the amount of oxygen delivered to the brain, which would induce quicker response to stimuli.


We collected the resting heart rate of each subject, as well as their heart rate 60 seconds later. From this data we derived a recovery index by subtracting each subjectÕs resting heart rate from his or her recovered heart rate after 60 seconds following activity and divided the result by the resting heart rate. We then compared the results of each subjectÕs recovery rate with their average visual and auditory brain reaction times. We used a regression analysis of recovery index versus reaction time.  A linear regression analysis showed that there was not a significant correlation (p=.403) between the recovery index and brain reaction time. 


Our results did not support our hypothesis.  We could have improved the test by using more subjects and adding an increased amount of repetitions for the tests administered. We also could have used more accurate equipment to create more equal amount of exercise such as a treadmill which would give us a controlled variable,  The data collected from the heart rate test was inaccurate because we measured each subjects radial pulse by touch.  Another possibility is that we could have recorded a more accurate heart rate by using a sphygmomanometer and a stethoscope. The data we used could have been slightly inaccurate because we measuring each subjects radial pulse. We also had each subject jump up and down for two minutes at their own pace; therefore, we could not control the intensity of each workout.  A treadmill could have forced each subject to run at the same set speed, which would allow us to control the intensity and make the test more accurate. Now that we have completed the overall experiment and analysis phase, it seems pretty obvious that there would be no relationship in the two variables we tested.  For example, many people play videogames and do not engage in that much physical activity, but their reaction time could be just as quick as an Olympic sprinter. What we have concluded is that reaction time is based on many outside factors distinct from heart rate. The alternative and accepted hypothesis states that recovery rate is not a precise reflection of brain reaction time.