January 10th, 2018
methodology – effects of diurnal changes, postural changes and temperature on heart rate and blood pressure
A male university student, healthy with no disclosed health problems aged twenty three years. The subject weighs 80 kilograms, does not exercise regularly, is a light smoker and moderately drinks alcohol.
Experiment 1: Heart rate monitor, pen and writing sheets
Experiment 2: Heart rate monitor, pen and writing sheets
Experiment 3: Heart rate monitor, thermometer, water, water cooler, ice, water heater, pen, writing sheets and a large plastic container that comfortably fits the feet and legs up to above the knees.
Experiment 1: the procedure consisted of taking pulse rate measurements every morning at 6 am and every evening at 6 pm for seven consecutive days. It involved seating on a chair and relaxing for five minutes. Then a heart rate monitor was used to take the pulse rate over a 30 second period. The readings for each day were then recorded on a sheet of paper and this was repeated for seven consecutive days.
Experiment 2: this experiment was performed by relaxing in supine position for five minutes and then taking the pulse rate over a 30 second period and recording it on a sheet of paper. After standing upright quickly and with minimal movement, another measurement of pulse rate was done immediately over a 30 second period and the results recorded on a sheet of paper. Other measurements of the pulse rate were done after two minutes and four minutes respectively after standing up, and the results recorded.
Experiment 3: this experiment had two parts.
Part 1: this involved getting a large plastic container that fits the feet and legs up to above the knees and filling it with warm water of a temperature of 35oC. The pulse rate was measured before immersing the feet and legs into the water-filled container and recorded. Then, after immersing the feet and legs into the warm water for ten minutes, another measurement of the pulse rate was taken and the result recorded. The feet and legs remain immersed in the warm water and the temperature of the water is maintained at around 37oC by the addition of more hot water. Other pulse rate measurements were done after 20 and 30 minutes while still immersed in water and recorded.
Part 2: this involved filling the large plastic container with cold water of approximately 10oC and adding a block of ice to keep it cold. The pulse rate was measured before the feet and legs were immersed into the cold water-filled container and recorded. The feet and the legs remain immersed in water and pulse rate measurement taken after 10 minutes while they are still immersed it the cold water and the result recorded. The feet and legs remain immersed in the cold and more ice added to keep the water temperature low until other pulse rate measurements are taken after 20 and 30 minutes and results recorded.
Limitations of the Methods
The lifestyle, fitness and medical history of the subject are not known. Maybe there could other underlying factors affecting the heart rate.
Only one subject is used in the experiment. This could result in biased results.
The activities performed by subject, food or drugs taken before the time of the measurement may influence the results.
Remedies to overcome limitations
The methods could be improved by assessing the subject to determine any underlying medical conditions, the fitness level and lifestyle to determine how they will be affecting the results. The experiment could also have increased the number of subjects involved in the experiment to three or more and finally, the activities and the environment of the subject should be considered; the subject should ensure they are consisted each day for experiment 1.