If you want to learn how to swim properly - you may as well get some tips from the best.
Olympic swimming champion Rebecca Adlington tries to improve Sportsround's Jon's swimming style.
Will any of her Olympic magic rub off?
You can watch the next Sportsround at 6.30pm on Friday on the CBBC Channel.
If you miss it, or really liked it the first time, you can catch it again at 7.25am on Saturday on BBC2.