I find that following various protocols isn't the most effective way. What's worked best for me is simply doing racing on zwift - there's nothing quite as motivating as trying to catch someone up in a race and I've scored higher heart rates doing this than anything else (inc FTP/ramp tests / very hard workouts etc.)

It's actually a very clever response by the body. If you're lying down you can recover far faster because the heart doesn't have to pump blood up the length of your body. Still, it's not a good idea to get dizzy.

Losing weight isn't quite as simple as it seems. Water retention is a thing too, also how often you go to the toilet, accuracy of your scales etc..etc.

Yeah also a good comment. It could be that you're stressing your body too much in one go when it's not experienced it before. Do these intense runs more often and but maybe not for so long and you'll soon find it's normal.

Oh, and at 22 you can take on the world ;) I'm also 35.

Agree here. You want to be more careful of pushing youself so much that you lose form and then injure your knees or fall over - these are more real dangers, and running out in sub zero temperatures you really need to be careful about slipping up.. your running could soon end if not.

Congratulations Joe. It takes a tough mind to overcome being fat. Remember, it's all in the mind :)

You should try doing negative pull ups and dips etc. This would be a good addition to what you can already manage. Keep pushing and you'll soon be back to where you were