Workout complete clothing

Hello everyone šŸ‘‹šŸ»

Has anybody here purchased workout complete leggings? If so, could you give me a rough guide on sizing? Iā€™m a UK 12-14 and according to the size guide I would need the biggest size available. That might be right, but I just wanted to check to see how other people found the fit. Thanks in advance šŸ˜Š