iWatch activity

HI All... can someone please tell me why when I hike with my husband, we both start at the same time and walk side by side the whole time, and at the end of the hike, I am .25 miles behind him yet the time is still exactly the same? It shows that we are identical in distance to .31 miles, then my tracker starts to fall behind starting at .02 miles and ending at .25-.30 miles behind him. We walk two miles every night, and we are identical in time and distance.

Also, when walking up a steep hill, and we slow down, it appears I get farther behind. I don't think this is right. Do I need to bring my watch in for repair?

Any help is appreciated.

Thank you!

mmwyatt725