why does the heart beat faster when your execising?
543383
In order to pump more blood to your body to keep it moving.\n\nWhen you are exercising or physically exerting yourself, your muscle cells need more oxygen and more energy, which is transferred through the blood. Your heart beats faster in order to compensate this and to pump blood more quickly.
1082572
When threatened, real or imaginary, the body produces adrenaline which is a natural enhancement to get you ready to either run fast to get out of danger or increases your responses to enable you to fight, ie quicker reaction time, strength is somewhat greater, that sort of thing.  It is a natural function of the body to protect itself from harm.
459792
Yes, that happens to me sometimes and it's so annoying, or I'll focus on my heartbeats and then I get palpitations.  I think it's a pretty normal reaction because those functions are controlled by the unconscious part of your brain, and when you focus on them your conscious brain is trying to take over.  Don't sweat it!
965197
No, this is not uncommon at all. When you sustain any type of injury, your heart beats faster and as a result, you start to sweat. This happens more often with blood wounds, because typically when you bleed, or see blood, your heart tends to beat faster then say, if you bruised your knee or something. So it's not "gross or rank", you just have a very up-to-speed heart. Hope this helps!
11671
How does the heart beat?\n\nThe atria and ventricles work together, alternately contracting and relaxing to pump blood through your heart. The electrical system of your heart is the power source that makes this possible.\n\nYour heartbeat is triggered by electrical impulses that travel down a special pathway through your heart.\n\n    * SA node (sinoatrial node) – known as the heart’s natural pacemaker\n      The impulse starts in a small bundle of specialized cells located in the right atrium. The electrical activity spreads through the walls of the atria and causes them to contract.\n\n    * AV node (atrioventricular node)\n      A cluster of cells in the center of the heart between the atria and ventricles, the AV node is like a gate that slows the electrical signal before it enters the ventricles. This delay gives the atria time to contract before the ventricles do.\n\n    * His-Purkinje Network\n      This pathway of fibers sends the impulse to the muscular walls of the ventricles, causing them to contract.\n\nAt rest, a normal heart beats around 50 to 99 times a minute. Exercise, emotions, fever and some medications can cause your heart to beat faster, sometimes to well over 100 beats per minute.
885495
Your heart is not controlled by sound.  If you hear a particular sound and your brain interprets it in a way that makes you stressed or excited, your heart rate may go up.\n\nAn example of this would be hearing a siren right behind you when you are driving - that will make most people's heart rate increase.\n\nHeart rate is controlled by your sympathetic nervous system.
148506
I would guess it's a side effect of sympathetic tone.  The sympathetic nervous system attempts to speed up the heart rhythm and make it contract with more force.  The sweat glands also respond to this same kind of sympathetic signal.
66013
I am no doctor, but I personally believe that any mind-altering thing lessens one's ability to reason. Once reason is gone, the person is simply reactive. If they react faster, it is because they lack ability to think about, or weigh, their response. It may not necessarily be anger; it may be laughter, fear, sadness, anything. If the response came too fast (without thought, or reason) -then I  say "Yes", drugs made that person's fuse very short.
526358
It's a little high. But that could be from you being edgy, having just drank a soda (caffiene speeds up your heart rate) and out of shape. Best way to get it to go down is exercise. I'm fairly in shape and my resting heart rate is about 70.
588418
No....your breathing rate doesn't jump that fast...and if you've been running for a while, you'll be exhaling as fast as you inhale....
540302
Working out increases body reactions and heart beat. Increased heart beat increases blood flow. Increased bloodflow and pressure from the heart to other parts of the body and from other body parts to the heart makes the veins to bulge. This is a natural thing that happens to all human beings.
649042
its your heart beating,\nif you hear it really often it could be a sign of anemia. which is easily treated.
373714
if you feel in danger or nervous than your body prepares you to run...this means your heart rate will increase ready to keep a good supply of oxygen to your muscles. this is normal, although you don't want it to happen to much as it can cause problems...if your worried at all than go and see a doctor.
474982
the mouse's heart beats at a higher rate because its metabolic rate (which is measured by the amount of oxygen consumption) is much higher than the elephant's. so, it needs more energy (this case oxygen) to survive, so the heart has to work faster to pump the blood that carries the oxygen through the body for its cells to utilize.
40640
Anything that can effect emotion will effect the heart rate.  Music can cause emotional reactions, so that if you enjoy a certain song and are happy to hear it, when it comes on your heartrate will increase.  The same is true for a song which you find dull or sad, which will cause your heartrate to slow.  It is the same effect as seeing a loved one, or hearing their voice- everyone knows that when they see someone they're attracted to, they can feel their heart racing.  The body responds mechanically to emotional directives.
786729
i would imagine that it's because your body wants to breathe, therefore causing the involuntary movement, but you don't want to breathe, which results in the voluntary contraction of your muscles. this, in turn, would cause a twitch-like movement. although honestly... i think somebody is cheating at the "hold-your-breath" game.
675301
You might be working out above your ideal heart rate. Get a monitor and figure out what your ideal one should be and try to stay around that.