You can't get fit without puffing, panting and sweating - but you can still look stylish while you're suffering.
That's the premise for a new business, OMMactive, set up by Belfast retailer Mel Boyle.
The triathlete previously ran the online arm of his brother Peter's hugely successful Argento jewellery chain.
OMMactive, based on Belmont Road in east Belfast, hopes to carve a significant space in the fast-growing market for "athleisure" - fitness clothing that's designed to be worn inside and outside the gym.
According to Morgan Stanley, the sector has grown by an estimated 42% in the past seven years and is now globally worth £194bn.
A report from the investment bank said: "The athleisure phenomenon looks set to continue into 2016 and beyond, and is now on course to become one of the fastest-growing global apparel product categories in the second half of this decade."
OMMactive sells the Australian leisurewear brand Lorna Jane, which has just entered the UK market with a flagship store in Covent Garden, London, where it's taking on popular brands like Sweaty Betty and Lululemon.
"It's a huge name in Australia, with more than 150 stores, but is keen to establish itself in this part of the world where it's largely unknown," said Mel.
"Initially, I was planning an online-only business, but Lorna Jane wanted an offline presence as well. Having the store is working out really well because, as I learned at Argento, if you do something online, it can drive footfall instore too.
"And Belmont is a great place for this type of shop. Along with Ballyhackamore, it's a vibrant and quite affluent part of east Belfast, with smart shops and restaurants nearby, like Slim's Kitchen, and there are two private gyms, Virgin Active and David Lloyd, within a couple of miles, so that helps to drive custom."
OMMactive also sells its own-label fitness clothing, designed by Mel's wife, Niamh, as well as a New York brand, Alala. In addition, it stocks organic vegan protein powders and self-tanning products.
Mel, who launched the Stormont Parkrun last year, is also a keen marathon runner and has taken part in Ironman contests.
"I've a huge interest in fitness, so this kind of business really works for me. I enjoyed building the e-commerce side of Argento, working with my brother for six years, but it was time for me to set up my own business. My brother owns the shop unit, so I was able to negotiate a good rent."
The brothers' retailing relationship goes back a long way.
"We were street traders in Belfast for many years, selling Celtic-themed silver jewellery from a pitch which was, ironically, outside the building that now houses Argento's main store on Royal Avenue. I learned a lot from those early experiences," said Mel.
Mel gave up selling and moved into IT, working as a project manager for BT, before joining Argento. Now that he's going it alone, he's got his sights set on rapid growth.
"Lorna Jane is a strong brand and we anticipate expansion. We're looking at the possibility of a store in Dublin, and perhaps others in Scotland and the north of England," he added.