Physiology of Exercise

Procedure:

• Perform preliminary heart rate test while a person is resting before caffeine consumption of every test
• Give a person the designated amount of 160 mg of caffeine
• Examine the heart rate 15 minutes after consumption for a period of 60 minutes
• Repeat the test 4 times in a 15 minutes time span for 60 minutes

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Data Collection and Presentation

Collected Data:

Table 1. Effect of caffeine consumption on heart rate (Person 1 – 5)

Table 2. Effect of caffeine consumption on heart rate (Person 6 – 10)

Sample Calculation(s):

Table 3. Calculation of mean and standard deviation of heart rate (Person 1 – 5)

Table 4. Calculation of mean and standard deviation of heart rate (Person 6 – 10)

Table 5. Calculation of mean and standard deviation of 2 groups as a whole

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Mean of heart rate of Person 1 =

Standard Deviation of Person 1

Step 1: calculate the mean = 67.5

Step 2: calculate the deviations

Step 3: square the deviations

Step 4: calculate the standard deviation

                        

T-test Calculation of Person 1

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Summary of results:

The mean of the pre-test of heart rate turns out to be lower than the mean of the heart rate after caffeine consumption (82.6 < 84).

The calculated standard deviation of the pre-test of heart rate in comparison to the heart rate after caffeine consumption is from 11.1774 to 11.8533.

After conducting the T-Test to compare 1 variable (heart rate) before and after an intervention, the calculated t value is 0.9651

The two-tailed P value equals 0.3597

From the t-table distribution, critical P value of 5% (or 0.05) a degree of freedom of 9 is 2.262

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Conclusion and Evaluation

Interpretation:

On average, the resting heart rate of an individual is slight lower before the consumption of caffeine. As shown in Table 5, the mean of the pre-test of heart rate of 82.6 bpm is lower than the mean of the heart rate after caffeine consumption of 84 bpm. The standard deviation shows the spread of the data values around the mean to be around 11 to 12, which is a wide variation. This also reduces the accuracy of this data set because it is now between +/- 1 of the suggested normal distribution of values. At 5% critical P value with a degree of freedom of 9, the calculated value is less than the critical value. When the calculated t-value is less than the critical value of the t-table, it indicates a rejection of the null hypothesis. There is in fact a relationship between caffeine consumption and heart rate. After consumption caffeine, heart rate tends to rise in the first 30 minutes, as indicated in Table 1 and 2. The two-tailed P value was 0.3597, suggesting that there is a 35.97% chance of error.

Limitations of procedures:

• Flaws of this procedure include the non-classification of gender, age group, heart condition and caffeine tolerance. For example, a younger male athlete with low caffeine tolerance will demonstrates a higher average heart rate than one who has higher caffeine tolerance.
• Human errors occur with the lack of knowledge on how to operate the equipments properly. Holding the heart rate grip monitor properly between the experimenters and experimentees is important.
• An individual must completely by resting while testing for resting heart rate. Exercising during this operation will result in inconsistency.
• Equipment error is an additional limitation of procedures. After my experience with the Heart Rate Grip Monitor, on one occasion, one’s heart rate will start properly (i.e. 86 bpm). However, there are times when the result will show to be 0 bpm. When the starting point is at 0 bpm, the average will alter resulting in inaccuracy and inconsistency with other averages.

Procedure modification:

• Do not exercise or conduct any other activity while getting the resting heart rate.
• Read the manuals and know your procedures prior to conducting the experiments.
•  Categorize individuals into either gender or heart condition (between an athlete and sedentary individuals) to increase reliability.

Bibliography

Elrod, D. (n.d.). Doug Elrod's Scalable Normal Curve. Retrieved from http://www.csic.cornell.edu/Elrod/t-test/t-test-toc.html

OverCaffeinated Organization. (2006-2008). Retrieved from OverCaffeinated.org: http://www.overcaffeinated.org/effects-of-caffeine-on-the-body.php

The GraphPad Software Inc. (1995-2009). Retrieved from GraphPad Software, scientific graphing, curve fitting & statistics: http://www.graphpad.com/articles/interpret/Analyzing_two_groups/choos_anal_comp_two.htm

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