The 4 x 4 Challenge This challenge can be completed in a team of 4 or on your own. It involves completing, 4 x 10.24km runs in a month, or a team of 4 taking on a 10.24km run either together or at different locations on the same day. Add all of your evidence to the runners portal and we will calculate your individual or team marathon time. This is a great challenge for groups of friends, work colleagues or individuals.