Biology

Body changes during different states are extremely complex evident from the many changes in observable respiratory variables resulting from the interaction between various organs, cells and systems. This projects seeks to determine the various physiological changes that takes place within an organisms body during exercise through the assessment of the respiratory rate, body temperature and other cardiovascular responses. Exercises often subject the human body to conditions that require compensatory adjustments, an aspect that can be determined through the observation of various body changes such as changes in body temperature, respiration rate, Skin temperature, and the blood pressure. During exercises for example, the heart rate will determine the number of heartbeats per unit and will often vary increasing during exercises, a state where the bodys needs for oxygen increases.
Other changes of interest during the experiment are inclusive of Tidal volume which will determine gas volume exchanges (O2 and CO2) during the exercise, respiratory rate, indicative of the changes in the number of breaths humans takes within certain time durations during exercise and the blood pressure which is a vital sign of the pressure exerted on the walls of the blood vessel by the circulating vessel.  Respiratory related observations will be extremely helpful in determining various body changes during exercise. Oxygen and Carbon Dioxide consumption and clearance levels respectively will be of great importance in defining respiration during exercises.
Respiration, a primary component of the mammalian physiology the process by which oxygen is transported from the clean air to the tissue cells and the carbon dioxide in the opposite direction, (Lister, Hoffman  Rudolph, 1997). Imperatively, individuals exhaled air that contains Carbon dioxide which is a waste product of the energy producing biochemical reaction that takes place within the cells during exercise. A number of studies have also indicated that ventilation increases considerably with the increase in lung ventilation received during sustained exercise, (Lister, Hoffman  Rudolph, 1997). The experiment is of great importance in a number of ways it will assist medial professional in diagnosis and tracking of medical conditions. It will also be of great interest to athletes assisting them to monitor physiological changes thereby gaining maximum efficiency from their training. Coaches, sports scientist and sports councils can also find the experiment beneficial in a number of ways. The experiment will also be of interest to the students of physiology and biological sciences and respiratory therapists.  
Hypotheses The experiment proposes to test the following hypotheses
1We hypothesize that the heart rate values will remain uniform at rest points, increase rapidly at the onset and throughout the exercise period, and drop rapidly during the recovery phase. 2 Carbon dioxide clearance is expected to remain on average at rest position, increase rapidly during the exercise before decreasing rapidly during the recovery phase.
3 It is also hypothesized that oxygen consumption is directly correlated to the levels of human activity, hence is expected to be low during rest, increase during the exercise and reduce rapidly during recovery. 4 Based on the expected temperature changes, we hypothesize that temperature and the body activity are directly correlated. Increase in body temperature with increase in the activity of the subjects during the exercise is expected. 5 Hemoglobin saturation is expected to remain constant during rest, increase during the exercise, decrease rapidly to the rest level during recovery before increasing with the increase of the recovery duration.
Method
Physiological changes in three human subjects aged between 18 and 21 were observed under laboratory conditions.  Critical to the experiment is the attainment of three sets of data representative of the rest, exercise and recovery conditions. At the outset, two measurements of the initial body conditions were taken at time zero and 3 minutes to determine the resting data points. The subjects were exercised on a treadmill, with its speed being progressively increased while data taken after every three minutes with the exercise phase lasting 9 minutes for all the three subjects. For the three sets of data, maximum heart rate for the experiment was specified as 177 and 172, 173 and 168, and 171 and 166 bmp for the male and female subjects beyond which the experiment was stopped.
The exercise heart rate was calculated and the values recorded this was necessary to predict the limits of the exercise since extremely high heart rates may endanger the health of the survivors besides being of an important indicator of respiratory changes during exercise. A number of instruments were used during the experiment the Spirometer was used to determine a variant data types inclusive of the CO2 Clearance, 02 Consumption. Values from the spirometer also aided in determining the tidal volume, respiration rate, vital capacity and the ventilation rate.  The heart rate monitor was used to determine the subjects heart rate while the blood pressures of the runners were measured using a mercury sphygmomanometer.
All the three subjects were seated during the collection of the resting data points which lasted for three minutes. The experiment did not have a control subject with the values from the rest position acting as the control to isolate the effect of exercise on the human body by holding constant variables comparative to those observed during the experiment. Two sets of recovery data were collected with the first one being collected three minutes with a reduced treadmill speed of 2 miles per hour while the second data set was collected when all the subjects were seated. It is imperative to note that a number of factors limited data collection only three sets of data rather than 7 were collected during the exercising phase since the heart rate of the subjects had reached critical limits.
This limited the calculation of other values such as the CO2 and 02 clearance, skin temperature, Hemoglobin saturation and systolic and diastolic blood pressure since the subjects could not continue with the experiments. Mean arterial pressure was determined to get the average of all pressure measured within specified time periods. To calculate mean arterial pressure, Systolic and Diastolic Blood pressure were applied in the formula
Mean Arterial Pressure (MAP)  (2Diastolic)  Systolic
                                 3
For example the first reading at rest position Systolic BP 112, Diastolic BP98
Applying the Formula, MAP (298) 112    102.6777 H 103
                    3
Oxygen consumption was obtained by calculating the difference between the amount of Oxygen delivered to peripheral tissues and the amount returning to the heart. Results
    There were significant variations in the data collected in all the three cases. For the first case involving male subject aged 21 years weighing73.6 kg and having72 inches in height with a resting heart rate of 63 bpm (noted as a non smoker), the heart rate increased to 1768, 191 and 204 within 3, 6 and 9 minutes of exercise. During recovery at a treadmill speed of 2 mph, the heart rate reduced to 144 before further reducing 3 minutes later to 64 at sitting position. Recoded tidal volumes were stable at 0.60 at sitting position, increasing to 1.00, 1.20 and 2.00 at 3, 6 and 9 minutes of exercise before reducing to 0.90 and 0.7. during the recovery phase. His respiration rate and ETC2 during times 0 and 3 minutes within the rest position were 30 and 25 and 40 and 72 respectively.
The respiratory rate was measured in breaths per minute. These later increased to 50 and 60, 65 and 65, 65 and 69 within 3, 9 and 9 minutes of exercise before reducing to 45 and 55 and 35 and 42 respectively during 3 and 6 minutes into the recovery phase.  For this subject, as a number of observable changes were made during the experiment. At rest for example, the subjects breath was easy, 3 minutes into the exercise, his breathing was still easy and running smooth however six minutes into the exercise, the subject was sweating lightly with his running difficult, his face also flushed. The subjects body temperature changes were also as expected with values averaging 34.75, 36 and 35 during rest, exercise and recovery phases respectively.
Fig. 1 Changes in Heart Rate

For the second male subject aged 19 years and weighing 72.48 kilograms with a height of 72 inches, the resting heart rate was determined at 75 bpm. The resting heart rate increased to 110 3 minutes within the sitting position, before increasing to 169, 171, 181, and 197 (bpm) within 3, 6, 9, and 12 minutes into the exercise respectively. The subjects tidal volumes were recorded as 9.60 and 1.00 at 0 and 3 minutes within the rest position. During exercise, the volume was observed as 1.00, 1.20, 1.30, and 1.60 (lbreath) within 3, 6, 9, and 12 minutes respectively. 2.20 and 1.60 (lbreath) were the observable tidal volume values during recovery.
Although the respiration rate for the subject was relatively stable at 25 breaths minute while in the rest position, this reduced to 18 breaths per minute 3 minutes into the exercise before increasing to 25 and 35 breaths per minute within 6 and 9 minutes into the exercise. Significant decrease occurred within 12 minutes into the exercise with the observable heart rate decreasing to 20 breaths per minute. During recovery phase, the recorded values were 20 and 15 at times 3 and 6 minutes respectively. Observable values of  O2 were 0.209 and 0.209 at 0 and 3 minutes during the rest position, 0.209, 0.213, 0.209 and 0.209 at 3, 6, 9 and 12 minutes respectively during the exercise. This averaged 0.209 during recovery.  
Fig. 2 Changes in carbon dioxide clearance

Data obtained for the third subject were on average, relatively low. The third subject was 18 years old, 66 cm in height and 65.6 kg in weight. The subject who was also a non smoker recorded a resting heart rate of 61 bpm although this increased to 69 bpm 3 minutes after the start first measurement. During the exercise, the subjects heart rate increased to 178, 123 and 208 3, 6 and 9 minutes into the exercise. During recovery, there were significant reductions in heart beat rate reducing to 163 and later to 68 at 3 and 6 minutes of recovery respectively. The subjects tidal volume were recorded as 0.60 and 1.00 at 0 and 3 minutes respectively during rest position, 1.00, 1.20, 1.30, and 1.60, at 3,6,9 and 12 minutes of exercise, and 2.20 and 1.60 at 3 and 6 minutes into the recovery phase.
Fig. 3 Changes in oxygen consumption

The following data were also observed andor calculated
Fig. 4 temperature
TimeSubject 1Subject 2Subject 3Resting Data points0 min3534353 min360.0234.534.5Exercise Data Points3 min---6 min---9 min-383612 min37--Recovery Data points3 min3737356 min353635Fig. 5 hemoglobin saturation
TimeSubject 1Subject 2Subject 3Resting Data points0 min9090903 min909090Exercise Data Points3 min---6 min---9 min-949212 min90--Recovery Data points3 min9090926 min909492Fig. 6 mean arterial pressure
TimeSubject 1Subject 2Subject 3Resting Data points0 min103790.023 min83790.02Exercise Data Points3 min--0.456 min--1.259 min-1032.4712 min104-Recovery Data points3 min77910.046 min95800.02
 Discussion and Conclusion
From the results above it is evident that both the Respiratory rate and the Body temperature increased during the exercise in all the three cases. It is also evident that the two variables are dependent upon the velocity of the treadmill hence the rate at which the body is moving.  Observations during resting are indicative of identical thresholds of panting with male heartbeats being higher than the female heartbeat. Heart rate observations for the three subjects support the hypothesis since it significantly increased although on average, all the three participants exhibited accepted levels of fall in heart rate after the exercise (Above 50 bpm). It has been observed that delayed fall in heart rate after exercise may be an important prognostic marker, (Powers,  Jackson, 2008).
Lister, Hoffman  Rudolph (1997) for example affirms that less than 30 bpm reduction one minute after the stop of exercise may be indicative of an impending heart attack, however, values of more than 50 bpm indicated a relatively healthy heart.  Results on oxygen consumption levels also supported out hypothesis with values remaining low during rest, increasing rapidly from the onset of exercise before stabilizing.  Temperature increase during exercise was expected since theoretically it is estimated that in excess of 70 of the energy that powers human muscles is lost as heat thereby leading to an increase in the body temperature, (Zheng, Sun, Li et al., 2008). There was also a direct correlation between increases in body temperature and the heart rate an observation that can be explained by the fact that the heart has to increase its pumping speed to ensure that the heat is pumped from the muscles to the skin surface for evaporation and cooling, (Evans  Meredith, et. al.1986).
The relationship between tidal volume and carbon dioxide clearance is also evident with carbon dioxide clearance decreasing with the increase in speed. Hemoglobin saturation is expected to remain constant during rest, increase during the exercise, decrease rapidly to the rest level during recovery before increasing with the increase of the recovery duration. This was an indication that for all the three subjects, the volume of oxygen per volume of blood increased with exercise an observation that can be explained by the bodys need of additional oxygen during exercise.  Conclusively, the data recorded strongly supported our hypotheses, indicative of the subjects relative health statuses
Significant deviations are expected based errors. Human error in taking values such as temperature values, timing could probably lead to deviations. Since certain values such as the MAP were estimates, the results were not exact hence were a probable cause of deviations. From the values obtained, the mean arterial pressure could be more valid comparative to a single value of systolic or diastolic blood pressure hence medical professionals should aim at calculating this value.  Additionally, they should check on the rate at which this value falls since if MAP falls significantly below 60 mmHg, then an individuals blood flow is not optimal.