How does Exercise affect the pulse rate

The blood carries the glucose and sugar which the muscles need to carry out their work.

There are some other very important changes in the body that take place during exercise. The arteries divide into smaller vessels called arterioles. The arterioles

have proportionally less elastic tissue and more muscle fibers then the arteries. The arterioles widen so that the blood pressure won’t go to high. In this way the distribution of blood to different parts of the body can be regulated. Blood gets pushed to the parts of the body that is needed the most and less where it is not needed. For example, during exercise more blood is needed from the guts to the legs. To make this happen blood vessels widen and constricts at different points. This is called, vasodilatation and vasoconstriction.

During exercise or when playing sport the increased respiration in the muscles generates more heat and therefore the blood gets hotter. To cool the body down more blood is pushed close to the skin. This makes the persons skin red. Lastly, the body also sweats a lot which cools the body by evaporation.

Immediately after exercise, the pulse will still be higher than normal, because the muscle may have used more energy than the blood could supply in the form of oxygen and glucose. The muscle will have to repay this "oxygen debt" by taking in more blood than normal for a time.      

Equipment

 To do my experiment I will be using a stopwatch. I need to use a stopwatch to record how long I have been walking and then to test my pulse per minute.

Variables

Before this experiment I made sure I didn’t eat a heavy meal because this would affect my walking and pulse rate. I made sure I wasn’t stressed as this would also affect my pulse rate. Other key variables would also affect the experiment such as:

• Age
• Gender
• Weight
• Height
• Medication
• Amount of exercise I do at home
• Smoker (nicotine is a stimulant)
• Stress
• Health including pregnancy
• Diet
• Temperature
• Type of exercise

I have taken all these into account to make the experiment a fair test because all of these would affect the experiment making it an unfair test.

To make this a fair test we did the same minute three times so that we can average the beats per minutes.  

Key variables  

One of the main key variables that is going to be independent is the length of exercise I do. It will be at rest and every minute for five minutes. The other key variable is dependant and this will change the pulse rate at rest and at every minute there after.

Method

Here is a step by step to show how I carried out this experiment.

Step 1

I will record my resting pulse, which will be 0 minutes. I need to show my resting pulse so I can compare all my results to my pulse rate before exercise.

Step 2

Secondly, I will walk for 1 minute and record my pulse after exercise.

Step 3

After I have completed the first minute I will rest until my pulse returns to its normal rate, which is 78 beats per minutes.

Step 4

I will record my pulse rate for two minutes, three minutes, four minutes and finally five minutes.

Results

Here is a table of my results:

The table of results show that the longer you exercise the higher your pulse rate goes up.

As the muscles started to work harder respiration was taking place in the body to provide extra energy for the muscle fibers. Breathing also increased to remove the carbon dioxide and consequently the heart started to beat faster pumping the blood faster around the body. The increased respiration in the muscles generated more heat and therefore the blood got hotter. As the pulse rate went higher the arterioles widened so that the blood pressure wouldn’t get to high.

In conclusion, the evidence gathered which is shown in the table above shows that my prediction is to be true. I predicted that my pulse rate would increase as I exercised more.

The outcome of this experiment met all the criteria’s for a reliable result. However, this result would have been very different if one or more key variables were not met. For example, if the person was overweight, asthmatic, under medication or even pregnant. Additional further work could be provided if the researcher wanted to predict whether pulse rate affected when one or more key variable was used.