Experiment to Measure the Heart Rate and Ventilation Rate Before, During and After Moderate Exercise

Before the exercise the breathing decreased when I was counting how many breaths I can take in a minute. However whilst breathing, my breathing rate was not normal but it was essential for me to keep the results reliable.

In addition a small rise in breathing rate and this is called anticipatory rise, this happens when exercising. The average reading for breaths per minute during exercise is 23-30. This shows that with more blood pumping through the body more oxygen is needed to keep the body at a sustainable rate to help our body create more energy. Our breathing rate will keep increasing until

Four interval times (PR, RT, TP and RR) measured in seconds were recorded both with the subject at rest and after the subject had exercised. The PR and RT intervals remained virtually unchanged with the PR intervals remaining the same both before and after exercise with an interval time of 0.15 seconds, and the RT interval increase by 0.01 seconds from 0.37 at rest to 0.38 seconds after exercise. More substantial changes were noted in TP and RR intervals. The TP interval decreasing from 0.32 seconds at rest to just 0.08 seconds after exercise, a decrease of 0.24 seconds (just 25% of the resting 0.32 seconds). The RR interval decreased from 0.84 seconds at rest to 0.61 seconds seconds after exercise, a decrease of 0.23 seconds

Exercise increases heart rate by a process of sympathetic autonomic stimulation. Sympathetic (adrenergic) nerves increase the excitability of the sino-atrial node and reduce the P-R interval .As exercise continues, the physiological changes in the body are continuously monitored by a number of physiological systems and the balance of activity of the sympathetic system (speeding up) and the parasympathetic system (slowing down) is constantly adjusted. When exercise is over, the heart rate does not drop immediately as the body has to undergo a period of re adaption to return to the resting state.

The respiratory monitor measured baseline respiration for a minute. Respiratory rate was also measured by the respiratory monitor throughout the entire experiment. After initial respiratory rate had been measured for about 30 seconds, researchers established a baseline heart rate range using the pulse oximeter. This was done by recording maximum and minimum heart rates within a period of 30 seconds. Since the site of the experiment had abundant background noise, silence could not be used as the control variable. Therefore, white noise was used as the control instead. The subjects listened to “Original White Noise” by White! Noise using Sony MDR7506 Dynamic Stereo Headphones. The subject was instructed to pedal at a rate between 8 and 10 mph and was supervised by an experimenter to ensure that the participant stayed within the proper pedaling speed range. As the participant pedaled, the researchers changed the resistance on the stationary bike between resistance levels 8 and 11 to make sure that the participant’s heart rate was within the preferred range. Subjects were monitored to ensure they had the heart rate ranges of 55-65% of his or her age-predicted heart range. The subject pedaled for two minutes,

During exercise there is an increase in cardiac output, which corresponds to an increase in maximal oxygen consumption. With the increase in oxygen consumption, a greater increase in blood flow occurs. This means there is more oxygen circulating in the blood for the tissues to take up. Due to the increase in blood flow, vasoconstriction of arterioles occurs to maintain mean arterial pressure (Bassett & Edward, 1997). This limits oxygen consumption because some of the blood flow is directed to the brain and skin. It is further pointed out that the heart is another limiting factor because it determines how much blood and oxygen are supplied to the muscles especially when blood flow exceeds maximal cardiac output (Bassett & Edward,

Once I started to exercise it caused my heart rate to increase and my breathing rate slowed down slightly. When I did the anaerobic exercises my heart rate went up higher than when I did the aerobic exercises.

The pulmonary ventilation increases when the body starts to do exercise, this happens because like most of the other responses the muscles need more oxygen, there is also an increase in the removal of carbon dioxide.

Research has shown that deep breathing exercises can induce an increase in heart rate (Sroufe 1971) because heart rate is also directly correlated with breathing (Egri 2012). When breathing in, heart rate will increase; and while breathing out, heart rate will decrease (Egri 2012). Blood pressure can be reduced with slower breathing (Joseph et al. 2005). An article in the Journal of Human Hypertension showed that doing breathing exercises over a period of time can lower both systolic and diastolic blood pressure (Grossman et al. 2001). The hypothesis in this experiment is that blood pressure and heart rate will be affected by a deep breathing exercise. The null hypothesis was that heart rate and blood pressure will be unchanged while performing a deep breathing exercise. This experiment is significant because it could help people in times of stress or anxiety/panic attacks to learn ways to calm their heart rate and blood pressure down so they may feel better. Being the most common mental illness in the United States and 18% of Americans living with it, research aiding recovery of panic attacks would be extremely useful to the public (Kessler et al. 2005).

Summary statement: Heart rate increases during and after exercise and begins to drop back down close to the basal rate after rest.

The circulatory system comprises of five main parts. These parts are; the Heart, Arteries, Arterioles, Capillaries and Veins. Each part has a specific role to play in the functioning of the circulatory system. The circulatory system works in a type of loop or closed system (www.about.com) (Craig Weber M.D).

Increase in exercise means there is an increase in muscle contractions. In order for your muscles to contract energy is needed. The energy needed comes from the aerobic respiration which involve glucose + oxygen to react together and make carbon dioxide + water. Increase in heart rate pumps more blood with glucose and oxygen. The breathing will increase to get rid of the carbon dioxide and to provide more oxygen, and the pulse will increase to provide the energy and oxygen needed.

During exercise your heart and breathing rates increase noticeably. The change is due to the increased needs of oxygen and other nutrients to the muscles in the body.

The literature on the effects of exercise of cardiac output maintains the idea that exercise should affect cardiac output- pulse rate, systolic blood pressure, diastolic blood pressure, QRS-pulse lag, P-T and T-P intervals, because of increased heart rate. For our experiment, we tested this theory by measuring our cardiac output before and after some rigorous exercise. We measured the individual cardiac output and then combined the data to compose a class-wide data average. We compared the results of the experiment to what we expected, which was that exercise does affect our heart. Our data from this experiment supported the notion that exercise does, in fact, change cardiac output.

The effects of heart rate on differing durations of exercise were studied in this experiment. For people, heart rate tends to increase as they perform physical exercises. The amount of beats per minute gradually increases as people perform physical activities. Heart rates taken before exercise are relatively low, and heart rates taken one minute after exercise increase significantly. Heart rates slowly begin to decrease after they are taken two minutes and three minutes after performing the step test, which is to be expected. The rates of intensity throughout exercise relates with changes in heart rate throughout the step test performed in the experiment (Karvonen 2012). The age of the participants affected the experiment, since the heart rate during physical exercise, in this case the step test, is affected by age (Tulppo 1998).