11mph is 5.3 minute mile pace. I agree with others that that seems unlikely. Treadmills can have calibration issues.
I'm also a hiker by background and have found that it doesn't cross over well to running. Road shoes are typically light and fairly smooth. The soles don't bear up well when hiking. Trail shoes can. Inov-8 shoes work for me for both running and hiking, but the only way you'll know if the work for you is through trial and error.
You may want to look at the LDWA for off road events where both runners and hikers are welcome. And, if you ever get into the ultra world, you will find you have cross-transferable skills.