With self-defence classes becoming increasingly popular, writer Susan Griffin finds out just how difficult it is to learn a few tricks to keep you safe on dark nights.

A few weeks ago, I was chatting to a friend on the phone as she was walking home one evening, when I suddenly heard her yelp before the line went dead. It was one of those heart-stopping moments when you know instinctively something awful has happened.

It turned out she'd been mugged by a man who'd run up behind her and covered her mouth with his hand. While understandably shaken up, fortunately she'd not been physically harmed but it served as a stark reminder as to how dangerous the streets can be.

The sad and awful truth is these things aren't the stuff of late night dramas but happen in real life and to ordinary women.

Now the dark nights have set in and with party season in full swing it's more important than ever to be vigilant.

"Walk confidently, don't talk on the phone while walking in the street and don't listen to music," says Daliah Terret, 37, a self defence and martial arts instructor at KB Fitness Self Defence.

"When you're listening to an ipod, not only are you displaying your property to potential robbers but you can't hear what or who's behind you. Your senses have been hindered and you're not concentrating, which makes you an easy target."

An ex-police officer who's been doing martial arts since she was six years old and now teaches self defence and martial arts classes, Daliah is the woman to listen to when it comes to protecting yourself.

It's why I decided to sign myself up to one of her self-defence classes.

Arriving at the hall, it's a surprise to find a third of the class are men. But then as Daliah later explains, while women are more vulnerable, "it's not about who's bigger or stronger because we all know that attackers will be bigger and stronger because they're cowards".

"It's about learning the techniques that allow you to remove yourself from an attacker, whether you're a man or a woman. You just don't want to fight anybody," she continues.

Self defence is not about fighting, it's about being aware of your surroundings so you can avoid becoming a victim in the first place. That as well as learning straightforward ways to release yourself from grips and locks if needed.

If you're anything like me, the thought of entering a fitness room of any sort is enough to bring on heart palpitations but it turns out that self defence is not about fitness and the class was full of people of all shapes and sizes.

The other concern was joining a class of people who were a few lessons into their course. Wouldn't I be making a show of myself and be lagging behind people who were busting Jean Claude van Damme manoeuvres? Fortunately, the concern proved unfounded.

"Self defence is as much a state of mind as body strength," says Daliah, which means building up confidence through revising moves from previous weeks.

"My advice is this," she adds. "Even one class is going to help because you'll learn something and it's better to know one thing than nothing at all."

And it's surprising what you can learn from just one class. After a brief talk about how to stay vigilant, we learn that the first thing to do if you're approached and feel threatened is to take a step back, place your feet a good width apart, put your hands palm out in front of you and say, 'Stop' loudly.

Importantly we also learn that if you do find yourself in trouble, one of the worst things you can shout is 'Help' because people are likely to turn a blind eye. As depressing a thought as that is, it's a reality, so shout 'Fire' instead, which is far more likely to get a reaction from passers by.

And then you run. "We always advise people to run away, never to fight, particularly over property because it's better to lose your property and be safe than have it and be lying somewhere on the street," says Daliah.

The first move down pat, it's on to a few basic techniques known as grab releases, strangle releases and strikes. They do exactly what they say on the tin and should help you get out of certain situations.

"Grab releases are very effective because you're using that person's joint manipulation and using the attacker's body weight against themselves," explains Daliah. The idea is to stun someone long enough for you to have the opportunity to run away.

It seems simple enough when watching the instructor do the move, but then we're asked to pair up and that's when things get tricky.

Taking it in turns to pretend to 'attack' each other, I and a few others in the class find ourselves simply freezing and forgetting the step we've been shown a mere moment before.

"If you're very frightened people generally just freeze and your mind goes blank," says Daliah. "You need to practise a technique about 400 times before it start to become instinctive."

But that's to practise in our own time. After about twenty attempts we move on to learning the techniques you should use if you find yourself trapped on the floor or against a wall. The instructor tells us about a girl who managed to get away from her attacker who'd trapped her against railings leaving her with only the fingers on one hand free. By bending her index finger and jabbing him in the space between the nose and mouth, one of the vulnerable pressure points, she managed to stun him, giving her the vital seconds she needed to escape.

"Anybody is capable of learning self defence," says Daliah. "We've had people who have been attacked and they attend the courses because they've lost their confidence and don't want it to happen again, while others do more than one course and see it as a continual progressive learning experience."

Good for your state of mind, as well as for learning important preventive measures, self defence classes are importantly also good fun.

Who wouldn't share a chuckle with their 'attacker', a person you've met only seconds before and are now pinning up against a wall or straddling on the floor.

What else can you do but laugh from a mixture of embarrassment and awkwardness? And then there's the weapons defence technique, which was a case of 'Hello', a quick handshake and the next minute my new partner and I were pretending to stab each other with a plastic knife.

When the class comes to an end an hour later, I'm no Bruce Lee but I've learnt some valuable techniques I'm ready to use if needed.