Fitness is better in bits.
There are a lot of ways to get fit. You could run a whole marathon! That's a big ol' chunk of fitness right there! But that's also a lot of work. An easier method is to get your fitness in bits. Walk 10 steps from your bed to your couch? That's one small bit of fitness. Take the stairs instead of the elevator? That's another bit of fitness. Flex your arm muscles while lifting a bag of potato chips up to your face? Yes, even that is one more tiny bit of fitness. Before you know it, you'll have accumulated enough bits of fitness to equal a whole marathon! It'll just be in five step increments, spread out over the course of months.