The same can be said about racing with no freewheels or derailleurs while smoking unfiltered cigarettes. That guy on PBS can still make damn nice furniture using all manual tools, it just takes him 10x as long and he usually ends up bleeding at some point.

If you wanted to get an HRM you could pick one up for $20-30 off Ebay. Otherwise go out and do simulated efforts of the things you want to improve hard enough that you hate doing them. If you're tired take a day off. Go by the dollar store and pick up a notebook and a pencil and keep a log so you can look back and see if something works or doesn't.