The body is far more complicated than we think

I'm a medical doctor, 5 months ago my weight was 115 kg. I didn't try to lower my weight before till this year when I saw many 30th years old patients dying from heart attack. I went with intermittent fasting and it worked well but I soon switched to extended fasting out of greed and I was losing 10 kg a month, now I'm 75. I did many 3 days fasts, some 5 days fasts and 7 days fasts 3 times, I knew that weight loss become harder and harder as you approach your goal but I have never thought that your body can get adapted to 3 days and 5 days fast as I don't lose weight doing them anymore! I do 100 push-up, lift weights and walk for 2 hours everyday even when I fast! I would love to watch a video regarding body adaptation to fasting (including 5 days fast) Thank you.