Avoid exercise burnout: "If your goal is to lose weight or improve your performance in the water, it’s not about swimming for longer - it’s about swimming smarter," she says.

Exercises such as walking, cycling, and yoga may be easier for older people to do regularly. ... The CDC notes that aquatic exercises, such as swimming, can help improve mood.

Most people’s 1K swimming time will broadly correspond to their 5K running time (assuming they’re not a total beginner to either activity). Give it a go and see which one you complete quicker.