It's a question that goes back to the beginning of time -- who's stronger, men or women? It's something that Brian Egwuatu and his wife, Kara Egwuatu, battle over all the time.
"Oh, Brian and I make everything a competition, everything; working out, driving home from work, running at the track," Kara Egwuatu said.
"Definitely, men are stronger, there is no doubt," Brian Egwuata said.
But now landmark research being conducted at The Texas Heart Institute by Dr. Doris Taylor and her team is proving for the first time that women, from their stem cells to their hearts, have got men beat, big-time.
"There's a difference in the underlying structure of every organ, the blood vessels, the liver, the kidney, the lungs," Taylor said.
She said you can actually see the difference.
Take hearts, for example. Taylor took male and female pig hearts, nearly identical to the human heart, and stripped them of all cells so she could study their basic structure. She found the female hearts (pictured below) were taught and toned, plump and muscular looking, like a picture of a heart you would see drawn in a book.
The male hearts (pictured below) were much softer, loose, thin-walled and generally kind of limp looking.
Holding up a male pig heart, Taylor said, "Look at this, it looks like an old, bad sock."
And then there are the stem cells, the body's super-powered repair system. Taylor's research shows female stem cells are six or seven times more powerful than men's in many cases. Not only that -- women have far more stem cells than men and male stem cells die out far earlier in life.
"What we are saying is, 'Wow, just look at these cells from women that are so much stronger and so much better.' If my cells are better than yours, wouldn't you want my cells injected into your heart to make it better, healthier?" Taylor said.
She said her goal in the future is to inject female stem cells into men and women who are suffering from heart disease, diabetes, kidney disease, and other diseases to repair the damage and hopefully cure the sickness.
After all, she said, "Stem cells are us, another reason women rock."
Taylor says all of these differences between male and female hearts and male and female stem cells may explain why men die from heart disease so much younger than women.