How Exercise affects heart rate

> keeping to the same pace of sit ups during the timing,

> resting till my pulse has returned to normal

> do repeats

> use the same person

> use the same exercise

Apparatus

The equipment I will need is:

. A stopwatch

2. Gym clothes

3. Test subject

Method

. Take your resting pulse

2. Start doing sit ups for 1 min and take your pulse

3. Do two more repeats

4. After your pulse has slowed do the same procedure but for 2 min.

5. Do the same for 3 + 4 min

6. Plot a graph

Prediction

As the time I do exercise for increases my pulse will also increase, this because as the Muscles use up the oxygen, the muscles will need more oxygen so the body will start breathing heavier and the pulse will quicken to get oxygen to the muscles quickly. The result of the muscles not getting enough oxygen leads to a by-product of Lactic acid, you can feel this when your are doing exercise by a burning sensation in your muscles. This can be dangerous so when you get a build up of lactic acid you should slow your rate of exercise and rest till the sensation subsides.

My Results

Exercise time

In min

Resting heart rate

Pulse

1 2 3

Averages

67

68

68

00

82

2

68

00

16

10

12

3

68

36

28

16

27

4

68

48

43

47

46

5

67

57

55

53

55

My results are shown in the graph, the one average Anonymous result is circled. This shows my results are precise and accurate, this means my results are accurate enough to make a firm conclusion.

Skill & Precision

To make my results accurate and precise I am going to use some skills, these are:

i. Able to use a Stop watch

ii. Able to do the exercise

iii. Ability to warm down

Conclusion

As the exercise increases in length the quicker the heart rate goes up. This is because the muscles use up the oxygen in the blood, and then need more oxygen. So the heart has to pump faster to supply enough oxygen to the muscles for them to carry on with there task without having the build up of lactic acid coursing pain for the body. So as one does more exercise the muscles will need more oxygen.

What I found out?

I found out that as the length of time used for exercising increases, the heart rate - pulse - also increases, this means that as long as the exercise time is greatened, the muscles will need more oxygen.

Back Ground Knowledge

When your heart muscles contract they force the blood into your arteries. Each beat of the heart pumps the blood along under high pressure.

The artery walls are elastic and stretch to take the blood. Then they contract and bounce back to force the blood along. This bouncing back can be felt and is called the "PULSE".

The rate at which blood is pumped around the body depends on the heart rate, During exercise, the cardiac out-put must be greater than while at rest. This is because the muscles need a constant supply of Oxygen to create the ACP, which is needed for the contraction of the muscles. Also the blood needs to carry the Carbon dioxide away from the muscles. During exercise the muscles need food and oxygen while getting rid of carbon dioxide so the pulse beats faster to make this all possible.

Luke Hammond