Want to change your life? Stand like a man! Expert claims this trick is the secret weapon for women in the battle against the jitters

Every woman has struggled with nerves. Whether a job interview, tricky encounter or first date, there's nothing worse than feeling your cheeks flush, heart race and confidence disappear - and knowing you have no way of stopping it.

That was until an extraordinary talk by Harvard Professor Amy Cuddy - now viewed 30 million times online - gave women a secret weapon in their battle against the jitters.

She aired research suggesting body language could be the key to success. The way we stand, sit and speak can boost the confidence-giving hormone testosterone by nearly 20 per cent.

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All women struggle with nerves, from interviews to first dates. Research suggests body language could be the key to success. Harvard Professor Amy Cuddy gave women a secret weapon in their battle against the jitters

In her latest book, she gives small tips that could make a huge difference to women's lives.

SHOULDERS BACK

Our body language says a lot about us. It tells others if we are powerful or not and whether to take us seriously.

It also affects our mind. When we adopt 'powerless' stances, they are reinforced: testosterone levels drop along with our mood and confidence.

When feeling powerless, we shrink our bodies - our chest hollows, shoulders slump, head bows and we slouch.

However, when we feel powerful, we make ourselves bigger. We lift our chin, pull shoulders back, spread our feet apart and raise our arms.

When we adopt 'powerless' stances, they are reinforced: testosterone levels drop along with our mood and confidence. When feeling powerless, we shrink our bodies - our chest hollows, shoulders slump, head bows

So why does this matter? Well, the postures typical of women are also those of powerless people.

No matter how we're feeling, we shrink ourselves to try to take up less space, whereas men expand. Just look around on public transport or in meetings to see this.

Women's body language is also generally less open than men's, which reinforces our feelings of powerlessness.

Anyone who's observed young children knows that girls are just as likely as little boys to throw their arms in the air, stand with their shoulders back, and plant their feet apart. But at some point, studies show this changes: boys continue to expand and girls to collapse.

To change this, women need to learn again how to stand just like the boys.

If you are too nervous to smile naturally, try this trick. Hold a pencil horizontally between your teeth for two minutes. This forces the contraction of the muscles around the mouth and eyes, as when smiling

BE WONDER WOMAN

A Power Pose is simply any position in which your body is expansive and open.

You take up a lot of space and hold your arms and legs away from your body.

With the Wonder Woman power pose, for example, you stand with your feet apart, hands on hips and chin tilted upwards. Or you can do the Starfish, feet apart, raised arms wide open.

By holding these poses for two minutes before a big meeting, a date or stressful situation you can make yourself feel more powerful, confident, assertive, less anxious, happier and optimistic.

But it doesn't just change our feelings - it affects hormones, too. Just this simple action increases levels of testosterone, the dominance hormone, by 19 per cent and decreases levels of stress hormone, cortisol, by 25 per cent.

This hormonal change can have a real effect on performance.

We found that people who carried out a power pose before a mock interview were much more likely to impress than those who had been asked just to sit down.

LOOK UP

Left: Frequent eye contact can come off as aggressive. Occasional upward glances - were found in tests to be more authentic. Right: A Power Pose is simply any position in which your body is expansive and open

We're all told eye contact is good, but actually too much is bad.

In one study, job candidates trying to make a strong impression through frequent eye contact did not do well. Interviewers found them blatant and fake. While we want to be powerful and connect with people - we do not want them to feel we are trying to overpower them.

Instead, direct eye contact with occasional upward glances - were found in tests to be more authentic. The goal is intimacy rather than intimidation.

BITE A PENCIL

When they meet us, people judge us on two things: warmth and competence.

Perhaps surprisingly, the most important thing, even in a job interview, is that people warm to you. From an evolutionary perspective, it is crucial to survival that we know whether a person deserves trust. Only afterwards will they judge your competence. So how do you convey warmth? By smiling.

If you are too nervous to smile naturally, try this trick. Hold a pencil horizontally between your teeth for two minutes. This forces the contraction of the muscles around the mouth and eyes, as when smiling.

This makes you feel better by boosting happiness hormones.

FINGER POWER

Even your fingers can signal power. Hold your hands in front of your face with your palms facing each other and your fingers pointing upwards towards the ceiling.

Then touch your fingers tips and spread your fingers apart into a steeple, resting your elbows comfortably on the desk. This gesture is a sign of confidence. Police experts often use it when they are accusing suspects of a crime.

STOP HUNCHING

Don't hunch over your smartphone or tablet before an important moment - it will make you less effective.

When feeling anxious, however, our voices become high pitched - this is because the muscles in our larynx tighten with stress. Before an important meeting or work assessment, consciously lower your voice.

When looking down at a phone we mimick the posture of a person who is depressed - slumped over, with our neck and shoulders curved forward and head down.

Studies show that working on a small device for just five minutes can decrease assertiveness levels.

Keep your head up and shoulders back when looking at your phone, even if that means holding it at eye level. Use a desktop computer rather than a laptop - if you make a lot of calls at work, get a headset, so you can stretch out.

LOWER YOUR VOICE

Our voices communicate power - and not just through the words that they speak. Just as our bodies expand and take up physical space when we feel powerful, our voices grow.

We speak more slowly and take more time. We're not afraid to pause. We feel entitled to the time we are using.

Don't fiddle with your hair or necklace, it's a tell-tale sign of nervousness. Keep your hands on the table instead

When feeling anxious, however, our voices become high pitched - this is because the muscles in our larynx tighten with stress.

Before an important meeting or work assessment, try taking some deep breaths and consciously lower your voice.

This will help to relax the muscles which will help you talk more deeply and appear more confident.

...AND NEVER PLAY WITH YOUR HAIR

Don't fiddle with your hair or necklace - it's a tell-tale sign of nervousness.

Another telling gesture of powerlessness is wrapping a hand around the neck.

This is a throwback to a time when we had to protect ourselves from predators' jaws by covering the carotid artery. It shows that you feel anxious and threatened.

Keep your hands in the steeple position or on the table instead.

ADAPTED by Marianne Power. Presence: Bringing Your Boldest Self To Your Biggest Challenges by Amy Cuddy is published by Orion, price £20. To order a copy for £16 (20 per cent off) go to mailbookshop.co.uk or call 0808 272 0808. Free p&p on orders over £12. Offer ends February 18, 2016.