If fitting in 20 minutes of meditation seems daunting, here's a life hack that might help. In James Clear's book Atomic Habits, he talks about what he calls the "two-minute rule", which is designed to make any new habit or activity seem manageable. 

"The principle is that any activity can be distilled into a habit that is doable in two minutes," he says. "Want to read more? Don't commit to reading one book every week - instead make a habit of reading two pages a night. Want to run a marathon? Commit to simply putting your running gear on every day after work."

So instead of writing off your meditation on any day as unworkable, just commit to going and sitting somewhere for a couple of minutes in silence.

By doing that, you'll get a nice brief break from your day and you won't be putting any pressure on by committing to a full 20 minute session. 

As Clear puts it: "Once you’ve pulled on your running shoes, you’ll probably head out for a run. Once you’ve read two pages, you’ll likely continue. The rule recognises that simply getting started is the first and most important step toward doing something."

Once you've closed your eyes you'll probably find you've got time to meditate after all. 

I've been trying out the principle with yoga. Rather than committing to a 60 or 90 minute yoga class everyday, instead I'm aiming for only ten minutes, at home in the morning. Already, after only a few weeks of doing a minute or so each on certain poses I struggle with, I've been able to hold a headstand for 30 seconds and get myself up into (an approximation of) a wheel, getting slightly better each day. 

If you break things down into small (atomic!) chunks they're much more manageable.