To celebrate our milestone of reaching 5 million Wattbike Hub session uploads, and to help support NHS staff, the Wattbikers Challenge is back!

This time you'll need to give it your all for 5km.

#Wattbikers5k is the perfect opportunity to come together with fellow Wattbikers from around the world and put in your best 5km effort. Test yourself against elite riders, your friends or just focus on your own time, and see how you measure up on our leaderboard.

It’s completely optional, but to help us support a good cause (NHS Charities Together), why not use it as an excuse to ride 5KM, tag 5 people to challenge them and donate £5.

Our #Wattbikers5K winner will receive a bundle of Wattbike kit, and obviously the glorious feeling of beating some of the very best athletes the world has to offer.

You can keep an eye on the leaderboard to see how the very best are getting on, and what you need to beat.

View the leaderboard here: https://hub.wattbike.com/5k

Donating through JustGiving is simple, fast and totally secure. Your details are safe with JustGiving - they'll never sell them on or send unwanted emails. Once you donate, they'll send your money directly to the charity. So it's the most efficient way to donate - saving time and cutting costs for the charity.