Adapting from Treadmill to outside

nfpeacock

This is kind of a weird question but here goes. I can run pretty easily on the treadmill (cruisy speed, just as long as I've eaten first). I'm doing a colour run after the summer and have ran 5km a few times on the treadmill without much bother.
The other day I decided to go for a run outside. After about 5 minutes though i was smashed, and had to walk the rest of the way. I knew it'd be a different impact on my feets/knees etc but am I missing something?
Advice on how to handle the switch?

TAsunder

Is it possible you were simply running faster than you do on the treadmill?

What do you mean by "smashed" exactly?

Eric_DeCastro

yeah it is different running outside than it is running on a tread mil. for one the floor doesn't move under your feet. You actually have to propel yourself forward. I'm sure after a few outtings you will get used to it and it won't bother you anymore. just keep at it.