Mr Saenger, from Biddenham in Bedfordshire, will take part with teammates Tim O’Leary, Jon Ross and Lawrence O’Leary, to raise funds for Bedford-based Food Etc and AMMF, a bile duct cancer charity.
Extra Miles Challenges has so far raised about £1.9m.
Grandfather Mr Saenger said he had taken part in the event for 18 out if its 22 years.
“I’ve had such great memories,” he explained.
“Every year has been a highlight; the friendships we’ve made and the comradery make it so special.
“This is the last bang. On one hand I’m really excited as we’ll make this one particularly special but it’s also sad that it’s come to the end.”