Can't sprint when I am on the ground

I am working on my server and I just have noticed that I can only sprint if I am flying. Can someone help me with that? thx

 

If you are using Godmode plugin, everytime you connect back you cannot run, and you need to ungod your self and again god. But only if you have godmode plugin.

 

Take a look at your thirst bar, is water at 0?

 

Do you do any exercise? That might help you get moving!