New mother Alex Jones is taking on a set of gruelling physical challenges for Sport Relief.

The One Show star, who gave birth to son Edward in January 2017, will battle freezing temperatures and agonising blisters as she travels across the UK for a relentless schedule of swimming, hiking, cycling, caving and running.

The 40-year-old presenter is teaming up with four other mums from around the country for The Mother Of All Challenges to help raise awareness of maternal health and raise cash for Sport Relief 2018.

Alex Jones (Tom Dymond)

She said: “I have taken on challenges before, but this is a whole week’s worth of tests. Tackling them as part of a team of mums makes this the most special thing I have done for Sport Relief.

“It will push us out of our comfort zones and really test us physically, mentally and emotionally.

“I can’t wait to get started with these fantastic women.”

The challenges start on Mother’s Day (March 11) at Loch Ness, with the group doing a relay swim in the lake, where the average temperature is 5C (41F) at this time of year.

Next they will lace up their hiking boots to conquer Helvellyn via Swirral Edge in the Lake District. The tricky mix of climbing and walking includes a daunting ascent of 2,854ft (870m) and a descent of 2,625ft (800m).

Alex Jones and the other four mothers in her team (Sport Relief)

The following day the mothers will cycle up three of the Lake District’s toughest passes, before they travel to Jones’s home country of Wales to navigate a maze of dark caverns to make it out of Porth Yr Ogof cave in the Brecon Beacons.

The final challenge, on March 16, will see the group tackle a relay coastal run across the hilly Welsh coast, taking in clifftop views, secluded coves and wild landscapes.

Viewers can follow the group’s progress on The One Show each night on BBC One during the week of the challenge.

To donate visit www.sportrelief.com/mums.