Which of the factors below lead to having a high pulse rate?
1. Adrenaline
2. High humidity
3. Staying in heat condition
4. Obesity
5. Stress
Pulse rate is determined by the autonomic nervous system, and is modified to account for the necessary blood flow through the body at any moment. If the autonomic nervous system (ANS) decides that the body needs more blood, due to any reason, then it will make the heart beat more frequently to increase the flow.
There are a few main factors that increase the required blood flow, and therefore the heart rate:
- Adrenalin - the "fight or flight" response to stressors is extremely powerful in humans, and the corresponding response is an increase in heart rate - amongst other things - to be able to deal with the expected fighting, or running, etc.
- Physical exercise - the extra blood required to deliver nutrients and oxygen to the cells when the body is exercising means that the heart will have to work harder, with a higher heart rate.
- Obesity - The physical change in body size means that, the larger one's body becomes, the more pressure the blood will need to get around all the various blood vessels, requiring more pumping from the heart. There also can be some artery clogging which makes it harder for blood to flow, which can lead to heart attacks.
- High heat conditions - When in high heat conditions, the body needs to remove heat faster, by radiating it outwards from the skin. One of the best ways to do this is by sending more blood to the capillaries in the skin, which involved dilating (widening) the main arteries of the body. this decreases the blood pressure and therefore requires more beating from the heart to maintain an acceptable blood pressure.
- Dehydration - If you are dehydrated, the amount of blood circulating through your body decreases. Your heart will try to compensate by beating faster, increasing your heart rate.
- Stress - A stressful situation sets off a chain of events. Your body releases adrenaline which causes your breathing and heart rate to speed up.
There are many more factors which affect the heart rate, and can even overpower the effects listed above sometimes.
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