Pure Gym, which opens its eleventh Scottish site this week, has unveiled Sir Chris Hoy as an investor and special adviser.

The six-time Olympic gold medal winner will act as ambassador for the business, which launched its first gym in 2009 and has driven the growth of the 'affordable fitness' market. Its latest opening at East Kilbride will take the chain to 100.

Sir Chris said: "I have followed Pure Gym's swift expansion over the past few years and have admired the way in which they have changed the gym market for the benefit of consumers of all ages, abilities and interests." He was "excited to have been given the opportunity to invest in the business".

The cycling legend will be advising Pure Gym on enhancing the overall customer experience, and supporting members in achieving their individual goals. He will also act as a consultant on potential new Pure Gym products and services.

The chain has more than doubled in size over the past two years, acquiring LA Fitness and its 43 sites last month, to become the UK's largest gym chain both by number of gyms and members, with over 530,000 nationwide.

Humphrey Cobbold, chief executive, said: "Having known Chris since before his retirement, I also know that he is not just interested in elite sports but is deeply committed to helping people of both sexes and all abilities be healthier and more active."