Control Freak

'The heart is a muscular organ in all vertebrates responsible for pumping blood though the blood vessels by repeated, rhythmic contractions."

Basically the heart is an insanely important organ in my body, it pumps oxygenated blood to feed my body's biological functions. So without one, I wouldn't exist.

Experiment One

Do I (physically) have a heart? Am I able to control my heart rate?

Well I am alive. I'm moving, breathing, eating and functioning as a human so I'm pretty sure I have a heart. Also if i look on my right wrist (only on my right) I can actually see my pulse. So I know that blood is being pumped through my body and therefore I do actually have a heart.
But can I control it?

Well first things first. I wanted to see how many times my heart beats per minutes normally. I remembered my science days at school so I decided to test it 3 times. I'm a little scientist, i am.
1) 83 BMP
2) 87 BMP
3) 81 BMP

So my average would be 83.6666666666 so lets just say 84

My next test was to see if i can slow it down. I read that putting a person's face in contact with cold water triggers bradycardia - which slows down the heart rate. After that I held my breathe for a minute (well...)
1) 78 BMP
2) 72 BMP
3) 76 BMP

So my average would be 75.3333333333 so lets just say 75

My last test was to see if I could speed it up. Not having gone to the gym in a couple of days/months I didn't think it'd be too difficult. I ran around for a minute each time, then checked my pulse.
1) 138 BMP
2) 140 BMP
3) 143 BMP

So my average would be 140.333333 so lets just say 140

In conclusion, I do have a heart (thankfully) and I can control it.

Does this prove I exist?