Day 3: In addition to splitting exercise up over the course of the day, I'm also trying to be on my feet more this week. Studies have found that when people sit, a fat-burning enzyme called lypase turns off. By standing, you can actually burn up to 60 extra calories an hour.

For those of us with office-type jobs (in my case, a home office job), sitting can take up a large part of the day. So in addition to trying to get three 10-minute mini-workouts this week, I'm also just trying to be more active in general. Here's a few things I've done:

• Moved my laptop to the kitchen bar, where I can stand while working. This really takes some getting used to; I keep wanting to sit.
  
• Removing the basket that collects odds and ends at the bottom or our stairs and taking things up as I find them, one at a time.
• Playing music all day, which encourages my three-year-old to keep the TV off and is the cause of some spontaneous dance sessions.
• Breaking up paid work and housework so that I never spend too long being sedentary.

Of course, it's five degrees here right now. If it were spring, my options for physical activity would be wide open -- walking, a bike ride, gardening. But with a small child, I'm housebound for a few more weeks until the weather starts to warm. Today has proved to me, though, that just because you're stuck in the house doesn't mean you're stuck being sedentary.