Abstract

First, an experimental subject lied still for ten minutes in a quiet, dark environment, after which the subject's pulse, respiration, blood pressure, temperature (internal and external), and amount of sweat were recorded. Next, a different experimental subject walked for ten minutes, after which the same parameters were recorded. A third experimental subject ran up and down stairs for ten minutes, after which the same parameters were again recorded. These results were then combined with those of other experimental teams in the class to obtain mean values for each parameter following each activity.

Introduction

"Metabolism is the set of chemical reactions that occur in living organisms in order to maintain

life. These processes allow organisms to grow and reproduce, maintain their structures, and

respond to their environments.

Basic body metabolic parameters:

— pulse,

– respiration rate,

– blood pressure,

– temperature and sweat, can be measured.

The objective of this lab is to compare metabolic responses to three different

levels of exercise." (LabExercisePhysiology.pdf, school notes 2009)

Discussion

As expected, all parameters except for the internal and external temperatures increased as the level of intensity of the activity increased. The temperatures did not increase much in the final activity because the body was dissipating heat by two mechanisms: sweating (excretory system), and increased respiratory rate (respiratory system). This removed excess heat and maintained the body at its baseline temperature. Another reason for the increased respiratory rate was to supply the extra oxygen demanded by the increased metabolism of glucose (C6H12O6) in muscle cells during the last activity. The pulse rate increased as well. As muscle activity increases, local chemical triggers produced by the muscle cells cause arteriolar beds in the muscles to dilate, resulting in increased local blood flow. When extensive muscle groups are involved at near-peak performance as in the last activity, this can result in a significant decrease in overall resistance to arterial blood flow. In order to maintain baseline blood pressure, the heart responds by increasing cardiac output via increased heart rate. Therefore the differences in blood pressures during the three activities were minimal.