I have a goal, to make pull ups my cardio. Kind of how babies struggle to walk but after some years they can do thousands of steps before they even begin to get tired. 

In the past days I have tried in this exact order: 100 pull ups in 16 minutes then again the day after. 100 in 12 minutes then again the day after. 

The fifth day I had some craze in my mind and attempted successfully 570 pull ups in 1 hour and twenty minutes

Today the craze got even weirder and I did 1050 pull ups and 1 chin up in 2 hours and 40 minutes. 

The first 5 days I always felt really pumped up through the entire workout but today I felt really depleted even though I was continuously drinking bottles of apple and orange juice, drank 5 liters in that timeframe. 

But I felt my muscles shrinking, they didn't really shrink cause I measured them afterwards but they got softer, I could push a finger deep inside my bicep. 

Also I didn't feel tired, could have done more but I had a strange unique feeling. 
It was between sleepiness and a  mild headache. 



I felt surely worse from 3 sets of barbell squats, almost passed out from squats, but the feeling was different...no dizziness, no vomit but I wasn't alright. 

The thing that worries me the most was that my biceps got smushy and squishy... Now they are back to normal though.