The number of homeowners saddled with "marathon mortgages" lasting into their 70s has tripled in the last five years. A marathon mortgage is a home loan with an extended repayment term of 35 to 40 years. It is called a "marathon" because the repayment period drags on longer than a traditional 25-year mortgage, meaning borrowers stay in debt for longer – and potentially into retirement. David Hollingworth, of L&C Mortgages, said the longer mortgages could "leave a monthly burden beyond planned retirement". A longer mortgage reduces the monthly repayment, making them more affordable day-to-day for home buyers.