Fit4Less has defended a billboard poster promoting its gyms as “light-hearted fun” despite coming under criticism.

The poster, which was first pictured in Sawley, Derbyshire, features a shrek-like character and has text saying: “Tired of being … Fat & Ugly? Just be ugly at Fit4Less”.

The poster has been criticised by campaign group Combat Bullying. Natalie Harvey, founder of the Nottingham-based charity, described the poster as “filth” on Twitter. She also told the BBC that such advertising was like “shaming people”.

Fit4Less, which is part énergie Group, has approaching 100 clubs and more than 110,000 members across the UK, Ireland and mainland Europe. The company said that it provides a selection of advertisements to its operators, which they can choose from. Andrew Croney, énergie Group’s communications and marketing manager, said the campaign is being run in other parts of the country and that the billboard in Sawley would not be taken down.

Defending the poster, Croney said: “The general response to the campaign has been very positive. The vast majority of people are seeing it as a bit of light-hearted fun. This has always been our intention.

“The whole idea behind this campaign is that it is designed to be different. Many health and fitness adverts feature the ‘young and beautiful’. This campaign is designed to engage with the wider community. It is designed to target people who do not respond to general health and fitness advertising and attract people who are not currently coming to gyms.”

Fit4Less came under fire earlier this year with a previous billboard poster of aliens beaming up a person into a space ship. Text on the advert read: "They're coming…And when they arrive they'll take the FAT ones first!"

At the time, Jan Spaticchia, énergie Group chairman and chief executive, said: “Fit4less is a brand that doesn’t take itself too seriously, the campaign is intended to be seen a light-hearted fun and we certainly don’t mean to cause offence. We truly care about the relationships that we build with the communities that we serve and our track record of helping people to transform their lives through health and fitness is testament to this.”

As part of the company’s expansion plans, it opened its first gym in Gdansk, Poland on Wednesday. Membership at its UK gyms starts at £14.99 per month.