Your cardiac out put is about 5 litres per hour. It may increase in severe exercise to 25 litres per minute. Your muscles get about 20 litres of blood supply, instead of less than a litre per minute. To meet the increased demand, your heart beats at faster rate. It may go up from 72 beats per minute to 180 beats per minute.
It's not good at all.
The nervous system causes the heart to beat faster when you exercise. It itself is not an organ but a system.
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The heart beat can increase due to stress and exercise. There are many other factors that can increase heart rate.
runing
Philip Lyle Cook has written: 'The effects of auditory stimuli on heart rate during exercise' -- subject(s): Physiological effect, Heart beat, Noise
when we exercise our heart beat increases due to the reason that during exercise the body need more oxygen which is carried by blood so more and more blood carrying oxygen is to move to the part for which we are doing exercise and so more of the work heart have to do to pump the blood so ultimately our heart beat increases
That depends on the nature of your exercise. Heart beat rises to meet your metabolic requirements. Normally the heart rate goes up to 100 to 160 per minute. It may go up to 180 beats per minute in severe exercise.
Your heart starts to beat at faster rate. The heart rate may go up to 180 beats per minute.
Michael Thean-Chong Liang has written: 'Effects of intensity, duration and frequency of training' -- subject(s): Exercise, Heart beat, Physiological aspects, Physiological aspects of Exercise, Respiration
1.) exercise 2.) Smoking
because you been doing alot