Event organisers are rallying around charities set to lose £4 billion due to COVID-19.
Thousands of fundraisers across the UK have been suspended given the ban on mass gatherings - leaving charities with an enormous shortfall that could result in closure.
In response, organisers of mass-participation sports events have created a new campaign to save philanthropic institutions.
The 2.6 Challenge begins on Sunday 26 April - the original date of the 2020 London Marathon (which raises millions every year) - and anyone can enter.
For the challenge, people are being encouraged to invent an activity based around the numbers 2.6 or 26 - raising funds or donating to Save the UK’s Charities via twopointsixchallenge.co.uk
The 2.6 Challenge is open to every person – and the only requirement is that the activity must follow the Government guidelines on exercise and social distancing.
Nick Rusling, Co-Chair of the Mass Participation Sports Organisers group (MSO) and CEO of Human Race, said: “The 2.6 Challenge can be anything that works for you.
“You can run or walk 2.6 miles, 2.6km or for 26 minutes. You could do the same in your home or garden, go up and down the stairs 26 times, juggle for 2.6 minutes, do a 26 minute exercise class or get 26 people on a video call and do a 26 minute workout – anything you like.
"We want people to get active, have fun and raise money to help Save the UK’s Charities by giving money or raising funds for the charity close to your heart.”
Paul Foster, Chief Executive at the Great Run Company, said: “The 2.6 Challenge is an excellent opportunity for all of us, and our network of amazing runners and partners from around the UK to do something to help the incredible UK charity sector at this challenging time.
He continued: "We know our runners put in a lot of time, training and fundraising to participate in our events and we encourage everyone to take part in The 2.6 Challenge to help raise important funds for the UK charity sector."
Funds raised from the 2.6 Challenge will give charities a fighting chance and soften a huge financial blow over summer.
If organisations can survive through a difficult period, they may be able to recoup some of their losses later in the year - with major events like the London Marathon and Great North Run rescheduled for autumn.
For more information on The 2.6 Challenge, visit twopointsixchallenge.co.uk.