Heart Rate Monitors

[OakLeaf]

I measure the distance I run with Google maps. On the lower left corner of the map, there is an icon that look like a ruler. Click on it and you then use mouse clicks to map your route on the map. The distance will be tallied on theft side of the screen. Here is a screenshot:

First you have to click on "MapsLabs" and enable the tool. I got that far - but I didn't see where you select for it to lock to roads. Where's that?