Depending on how lazy you are, you could try running in place with the Tabata protocol. For me, one beautiful thing about sprinting is that you can do it anywh

Depending on how lazy you are, you could try running in place with the Tabata protocol. For me, one beautiful thing about sprinting is that you can do it anywhere you have a sufficiently lengthy stretch of open, flat ground. You can also shorten the sprint and do more of them to accommodate less permissive situations. I've even done wind sprints in my basement!