Getting fit together could be the secret for a long happy relationship.

A new study has shown that two thirds (66 per cent) of British couples who exercise together say working out with their other half has improved their relationship – while 21 per cent said working out as a couple made them feel more attracted to their partner.

When asked which activities are most popular among those to train together, swimming (37 per cent), visiting the gym (29 per cent) and running (24 per cent) came on top.

The figures come from a survey of more than 7,600 UK adults, published by global sports retailer Decathlon.

Other findings from the Decathlon activity index include that 22 per cent of couples who are physically active together said they exercise as a couple to stay in better shape, while a similar number (21 per cent) said it reduces their stress levels.

“It’s interesting to learn that such a high proportion of Brits are exercising with their partners," said Joshua Gutteridge, sports manager at Decathlon.

“It’s clearly not just the physical benefits that exercising as a couple is having either, with a large number saying that working out together is having a positive impact on their relationship – meaning this could be the secret to a happy and healthy relationship.

"So, if you’re struggling to find the time to spend quality time together, exercise is still a great way to enjoy time with your partner whilst also feeling great about yourself in the process.”

The Decathlon Activity Index tracks rates of participation in sport and other physical activities across the year through a national survey repeated every month throughout the year.

To access the full Decathlon Activity Index, click here.