(NEW YORK) -- A kiss is one of love's small pleasures. But for basketball legend Shaquille O'Neal and girlfriend Nicole Alexander, a simple smooch requires some serious strain.
At 7 feet 1 inch, O'Neal towers above most women (and men, for that matter). But Alexander's petite 5 feet 2 inch frame -- two inches shorter than the national average for women -- makes the couple's height difference nothing short of shocking.
"The challenge for a couple that's asymmetric in height is to figure out how to experience collaboration," said Susan Heitler, a couple's therapist in Denver and author of PowerOfTwoMarriage.com. "When a man's head is above everyone else's, he can begin to feel like it's all about him, like he's in a separate world from her."
Heitler calls it tall man syndrome. And it means both partners have to make an extra effort to see eye-to-eye -- whether it's figuring out what to have for dinner or the logistics of physical intimacy.
Studies have found that men and women tend to choose partners according to physical traits, such as facial attractiveness, body fat content and, in women, hip to waist ratio. But for a relationship to last, relative size may be the more important factor.
A study published in July found that marriages were more fulfilling when the wife was thinner than the husband. And according to Polish anthropologist Boguslaw Pawlowski, the most desirable male-to-female height ratio is 1.09 -- a number achieved by David and Victoria Beckham.
But for guys like O'Neal, a height-matched mate is a tall order. To fit the 1.09 ratio, she would have to be 6 feet 5 inches.
Short of high heels, there are ways asymmetric couples can level the playing field.
"Height is a metaphor for power," said Heitler, adding that a big heart or a big personality can fill the gap in height. "Sometimes there's a small man in the big body, and the woman is picking up on that gentle soul and kindly person. Or maybe the woman is small but just a powerhouse kind of person with lots of energy and lots of initiative."
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