Kamala Harris grabbed the initiative before the debate even began with her assertive handshake with Trump and managed to keep the momentum for the rest of the night, a body language expert concluded.

Donald Trump insisted beforehand that the diminutive Democrat not be allowed a pedestal behind her podium, hoping his own 6-foot 3-inch frame would project a towering presence over the debate stage.

But it was Harris who dominated from the opening seconds after spending days holed up in her Philadelphia hotel room honing her techniques with a trusted group of advisers, according to body language expert Judi James.

‘Her greeting ritual of Trump allowed her to take instant control and the status higher ground,’ James said.

‘Walking across the stage with energy and intent she offered her hand to Trump and introduced herself. 

‘The Attribution Effect involves the lasting impact of creating an impression of leadership or power in the first few seconds of meeting and the rule of a handshake means that the host is the one who instigates it.

‘Trump looked nonplussed here. His power shakes are legendary but he was left responding with a weak-looking hand.’

The former president may have spent four years in the White House and 13 as the star of The Apprentice, but it was his rival who looked the more accomplished TV performer with her ‘direct and often intimate conversation and pitch to the viewer’, James said.

‘By looking straight into the camera as she spoke and introducing her words with attention-catching, personalized phrases like ‘Let’s talk about’, ‘Get this…’ and ‘Understand'. 

'She controlled our attention and made her points personal and relevant,’ the analyst said.

‘Hers was a talk to the viewer, enabling her to change minds and voting tendencies by flattering them.’

Trump on the other hand struggled to adapt to the audience-free studio environment after weeks of speaking to campaign rallies.

‘While Harris kept her tone chatty and intimate, Trump began to shout as though he were on stage,’ James said.

‘This technique might work with his large live audiences but in an empty studio it looked and sounded wrong and out-of-date.

‘He also used all the same familiar lines that he uses in his rallies, making Harris look and sound like the fresh message.’

The candidates’ microphones were muted while the other was speaking, but the cameras were still on both, and Harris made good use of her dead air time to project clear messages with her body language.

‘Her raised chin and brows, her shaking head and knowing smiles or her pursed lips all gave the impression of intelligent evaluation and mockery,’ James concluded.

‘But her coupe de grace was her pose with one hand placed to her chin.

‘She did this gesture twice as she turned to listen to Trump and it gave the message of superiority and evaluation.

‘She narrowed her eyes to emphasize disbelief at his words. At one point she watched him with a facial expression of pity.

‘His split-screen responses looked too immobile.

‘He seemed to have been briefed to not be too directly attacking but his smug, closed-lip smile and his narrowed eyes worked better with Biden than it did with the much sharper and more animated Harris.’

Harris knows the race for the White House is on a knife edge and that one of her best chances to move the dial was to get under his skin.

Trump, who had thrived in the debate against Joe Biden, looked ‘rattled’ by his younger opponent and at one point looked ‘visibly wounded’ by some of Harris’s well-crafted jibes.

‘She said how people at his rallies get bored and leave early and she used the word ‘fired’, his TV catchphrase, to say 81 million people fired him during the last election,’ James observed.

‘Trump’s blink rate increased and he became visibly angered. His tone rose to a shout, his lower jaw jutted, showing his teeth and at one point he even has spittle on his lower lip.

‘It also made him veer off-point verbally, throwing different subjects into his answers.

‘During his debate with Biden Trump came across as the younger man mocking a President who could barely put his words together. His was the voice you wanted to listen to.

‘Here though he seemed to have nothing new to offer, allowing Harris to bring the fresh energy and the voice that stimulated interest.

‘His lowest point came when, after Harris spoke repeatedly about her plans, Trump replied to the host who accused him of not having a plan, that ‘I have the concept of a plan’.

‘His claim that people are ‘eating pets in Springfield’ allowed Harris to burst out laughing before producing her expression of pity.’

Trump had won the toss ahead of the debate to decide who would deliver the final concluding speech.

But that allowed Harris to occupy the psychologically more prominent podium on the right of the viewer’s screen.

And despite losing the opportunity to have the final word, the current VP made the most of her sign-off to viewers.

‘When Harris did her solo speech summary she threw Trump two looks of utter contempt, turning in his direction with the ‘fun’ smile now gone from her eyes, and looking him up and down as though believing she had finished him off.

‘Harris’s coaching and planning paid off tonight as she scored winning points in nearly every aspect of her performance in this debate,’ James concluded.