Virgin Active is investing £100m in its UK sites over the next three years as part of a campaign to lure post-Christmas gym users to sign up as well as advanced preparation for an eventual stock market flotation.

The company, which was founded in 1999 and is owned by CVC Capital Partners and Sir Richard Branson's Virgin Group, said it will use the investment to refurbish its gyms and install a host of new equipment between now and 2017.

The investment programme builds on the £15m spent by Virgin last year to open nine upmarket gyms known as its classic collection, to attract more customers.

Matt Merrick, the managing director of Virgin Active UK, said that the £100 million represented a “significant step-up” in the business’s normal investment programme, but he insisted that it would secure good returns by helping to boost present membership of about 500,000, including children.

Merrick confirmed that the company, which has more than 270 clubs worldwide, remains a “strong candidate” for a stock market listing, although no date has been set out.