In this chapter we're taking a more fluid approach to fitness by giving you workout challenges that you can either throw into your routine when you fancy a change or use at regular intervals – every six weeks, say – to monitor your progress.
They're useful tools to have up your sleeve for a couple of reasons. Sometimes you might not fancy doing the session outlined in your programme. Instead of missing the session entirely, these challenges offer a back-up option that can be used whenever they're needed. They are also generally quick to complete so they can be used when you don't have much time. Some of the sessions take as little as five minutes to complete, but don't be fooled by the duration – each one of them offers a real test of fitness.
If you're using them to assess your progress then we suggest that you always record your score (the number of reps you complete or the time it takes you to complete the workout, for example) so you can
