ABSTRACT

The experiment was carried out in order to investigate varies factors affecting blood pressure and heart rate. The investigation performed four tasks each analyzed different particular aspect e.g. gravity, exercises, cognitive activity and human diving response. The examination focused whether these tasks have any impact on human heart rate or blood pressure in human body. The experiment was conducted using electronic sphygmomabometer in small groups of three. The research showed that exercises increases blood pressure and heart rate to supplement needs body of extra oxygen. The results showed also that diving response includes cardiovascular adjustments known to decrease oxygen uptake. Prolong apnea body response by a pronounced decrease in heart rate..
The main conclusion gained from the experiment was to prove that number of environmental factors not always directly connected like e. g. stress, can leads to internal body changes. +50 words

INTRODUCTION

Homeostatic control mechanism is responsible for keeping body fluid pressure on appropriate level. In humans a change in internal blood pressure imposes a significant change in heart rate and vice versa. To optimize work these two mechanisms, due to evolution many receptors and effectors controlling these processes have been evolved.
Heart rate is the number of heart beats in one minute. It is direct by conducting system. This autonomic rhythm of the heart can be altered by autonomic nervous system. Increased level of carbon dioxide in blood, temperature, stress or anxiety are main factors varying it speed. Blood pressure is proportional to the amount of blood exerts against the inner walls. It can be controlled by body using short-term mechanism responding within seconds or long-time which is slower to respond but maintain blood pressure at an appropriate level for most of the time.
Nervous system uses sympathetic and parasympathetic activity to keep blood pressure in a narrow healthy range. In short term respond medulla oblongata triggered from peripheral receptors sends signals to smooth muscle located in vessels leading to change in its diameter.
To regulate blood pressure feedback control systems rely on circulating hormones.
Secretion of adrenalin can increase heart rate and change blood pressure immediately. Renin-angiotensin-aldosterone hormone is a system operating closely with kidney and bororeceptors. Together, they are a main regulator of blood pressure and water balance.
In fact rate of heart pumping, volume of fluid, resistance in the circulatory, viscosity or thickness of the blood, stress, anxiety and disease have effect on blood pressure.
Normal systolic pressure in an adult varies between 110 and 140 mm Hg, and diastolic pressure varies between 70 and 85 mm Hg. The resting heart rate for the average person is between 70 and 90 beats per minute (bpm).

EQUIPMENT

1 electronic sphygmomabometer per subject
1 stopwatch per group
Couch
Ergometer
Two (2) Basins of Water (one at 0 °C and one at room temperature)

METHODS

For all experiment students should work in group of three. Each group should choose one healthy, asthma free experimental subject which would have to take physical part in all tasks. Second student should operating experimental devices and third collect the data.

Activity1:
Correlation between exercises, blood pressure and pulse rate.
Two activities were performed. Firstly subject was rest in sitting position 15 minutes and then blood pressure and heart rate were measured. Subsequently, subject performed 5 minute exercises on ergometer and immediately afterwards blood pressure and heart rhythm data using electronic sphygmomanometer were obtained.

Activity2:
Body posture and blood pressure dependence.
The subject lied down horizontally on a couch. The cuff of the sphygmomanometer was wrapped alternately around the right or left arm above the elbow. Firstly measurement for BP took place