When Big Brother's Lisa told her fellow housemates to 'squeeze it', she was onto a good thing. The former body builder claims she has sex at least once a day, and she reckons that focusing on her pelvic floor muscles is the key to a good sex life.

It's been estimated that between 50% and 90% of women have never experienced a vaginal orgasm. So unless they've all got very handy partners, or they're finishing the job themselves, that's a lot of unsatisfied ladies!

But all is not lost, recent research has shown that women who regularly work their pelvic floor muscles are three times more likely to achieve a vaginal orgasm.

For those of you that aren't yet 'at one' with your pelvic floor, here are our tips.

1) Locate the correct muscles by imagining you're trying to stop a wee mid-flow.

2) Contract the muscles and up at the same time. Remember, don't use any other muscles, your legs, bum and belly shouldn't move at all.

3) Keep breathing, you should be able to sit at your desk at work happily exercising your pelvic floor without a soul knowing.

4) Just as you'd target muscles at the gym, repeat the exercise 10 times. Have a break, and then do 10 more. Once you've got the hang of it, vary the speed. Try a set where you hold the muscles in for 10 seconds each time, then try a set where you only hold them for a second.

So come on girls, get squeezing!