About 12,000 runners and wheelchair racers are expected to set off from Wellington Street in Leeds city centre, racing to Kirkstall Abbey and back again.
Ms Major said Age UK remained the lead partner charity for the event.
“We’ll always keep the fundamentals at the core that Age UK have worked so hard on over the last nearly 40 years,” she said.
“But our aim is always to grow. So the more participants we can get, the more the merrier. We’re very excited to have it in our portfolio.”
Run for All is expecting a record number of participants, with many raising money for charity.
Ms Major said: “It has a huge community impact. A lot of people come in from Yorkshire and a lot of people are travelling from afar as well. It is a big event in the running calendar.
“We have a lot of people attending who are trying to get a personal best, but equally people who are running for fun, raising money for charity, fundraising, running with their friends and family.
“We do welcome all abilities and ages to take part. Whether it’s individuals or groups, there’s always some really inspiring and heart-warming stories.”
She advised those taking part to “keep an eye on the weather” as temperatures are forecast to be as low as 2C (35F).
“It might be a bit chilly, so plan accordingly. But all importantly, just have fun,” she said.
Road closures are in place for the event, including parking suspensions on Park Place, York Place and Quebec Street.
Roads around Wellington Street will be closed from 04:00 to 15:00 on Sunday, while the A65 will be closed from 08:00 to 12:00.
