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Statistical Data Analysis The recorded data for heart rate, systolic blood pressure, and diastolic blood pressure for all 150 subjects was analyzed using an excel spreadsheet. The average or mean for all three variables was calculated. The average percent difference between resting heart rate and heart rateafter each of the exercises (15 steps and 30 steps), and the average percent difference between systolic and diastolic blood pressures at rest and after exercise was also calculated. The standard deviation of the average values and difference in average values for the control and pre-treatment groups was calculated in addition to the standard error. The averages and standard deviation were used in an effort to find the p-value. The p-values for each variable illustrated the probability that changes in heart rate and arterial blood pressure levels were due to caffeine consumption. The p-value is based on the null hypothesis (i.e. there is not a statistical significance/difference between the control group and pre-treatment group) (4). Therefore, a lower p-value suggests a difference between the two groups due to caffeine consumption, while ahigh p-value illustrates that any effect that caffeine has on heart rate or arterial blood pressure is due to random chance (4). A p-value of equal or lesser value to 0.05 demonstrates statistical significance. A p-value higher than 0.05 suggests that the null hypothesis is true and there is no difference between the control group and pre-treatment group (i.e. any changes in the three variables is not due to caffeine consumption but rather random chance). 4
ResultsTable 1: Average Resting Values of Heart Rate, Systolic Blood Pressure, and Diastolic Blood PressureAverage Resting Values of Heart Rate, Systolic Blood Pressure, and Diastolic Blood Pressure: The mean of each the pulse count, systolic blood pressure, and diastolic blood pressure at rest is given by the average. SD= standard deviation, SE= standard error of the mean, the standard errorof the mean was calculated using the following equation: (SD/ square root of sample size n)Pulse countSys.BPDias.BP020406080100120140Average Resting ValuesControlPre-TreatmentVariableAverageFigure 1. Average Resting Values: Graphical Presentation of the data shown in Table 1. The bar graph shows the average resting values for the three variables tested (pulse count, SBP, and DBP) for control and pre-treatment groups. Error bars represent the standard error of the mean for each variable (see table 1 for values). The asterisk (*) above the average resting values for systolic blood pressures indicates that statistical significance was found. 5
Table 2:Normalized Average Change in Pulse Count after ExerciseNormalized Average Change in Pulse Count after Exercise: The average percent difference between the resting pulse count and the pulse count after the 15-step exercise and after the 30-step exercise for the control and pre-treatment groups. The average percent difference was