It might be a bit chilly here in the UK at the moment to go for a dip in the sea, but it isn't over in Australia.
Martin's been on the Gold Coast for the Commonwealth Games.
Now all the sport is finished, he's been to meet some amazing young people.
They all volunteer as lifeguards, which means they spend time on the beach keeping people safe and helping to prevent anyone from drowning.
They've been telling Martin all about what they do.