And the most important conscious decision you can make is what habits to acquire. Conscious decisions otherwise seem almost epiphenomenal, "say it, brother!" exclamations to validate unconscious decisions already made.
So I biked to work today, though the day never got above 15 F. I'd never start biking on a day like today, but I have a habit, and so it actually takes a carefully considered decision to keep me from biking in. Fortunately, the modern world is full of great equipment: with balaklava, neoprene booties, lobster mitts, and warm jacket, it's really not uncomfortable. The worst is the tiresome unpeeling when I get to work.
I've been too busy at work to get to the gym at lunch, so this has been my only workout for the past few days. If you have to exercise in order to get home, you are way more likely to do it.