Source: magazines.ivillage.com/redbook

No moment is as starkly defined for men as "Turning 40." That birthday instantly, magically transforms the most strapping young man into a toothless, decrepit old-timer -- in his mind. "There's not a major medical difference between men in their 30s and men in their 40s, but psychologically there's a big difference," reports Jaime G. Corvalan, M.D., a sexologist in Pasadena, Calif. "For the first time they realize they're mortal: They say, 'I'm 40, and I'm going to die.'"

Suddenly, they take their physical condition very seriously, paying renewed attention to diet and exercise. Aging is a dismal enough prospect, but when it starts to affect sexuality, it becomes downright tragic. Men can feel intensely emasculated when problems -- prostate trouble, lack of flexibility -- start cropping up. "I've gained some weight and that definitely affects what I can do," says Bill, 44. "Certain positions actually hurt a little."

It's tough on a man's pride, to say the least, and all this pressure and disappointment can culminate in that great bane of the 40-something man: the midlife crisis. "He starts to recognize he doesn't have the same physical energy and can't get an erection as often or sustain it as well -- in other words, he can't function as an 18-year-old anymore," says clinical psychologist Karen Shanor, Ph.D., author of The Shanor Study: The Sexual Sensitivity of the American Male. "He may ask himself, 'What do I want to be sure to do while I can still do it?'" And that can mean a self-reassuring romp in the hay with the office temp.

But the news isn't all bad. "Men often become better lovers in their 40s, because there's more concern about the quality rather than about 'getting it' every night," says Hillyer. If that pure, uncut stallion stamina is starting to wane as he heads up and over the hill, at least it's being replaced by maturity and experience, laying the groundwork for a potential bonanza for you. But for you to take advantage of your husband's well-aged, finely honed skills, it's important to start subtly adapting your foreplay to accommodate his changing physicality. "He's going to need a little more stimulation and more time to produce an erection," explains Dr. Cohn. Your husband may be inordinately interested in straightforward, athletic man-on-top sex, since part of the point of sex at this phase is to prove he can still do it. So indulge him, listen patiently to his Tarzan roar, and compliment his stamina afterward. (It's a guy thing.)

A big bonus for you is that the 40-something man is into the mutual act of sex more than ever now. While he may have been a good lover and attentive before, this is often the first phase in a man's life where he draws real, significant pleasure just from ringing your bell. Says Hillyer: "This is the time for a woman to really hold out for quality, for sex to be an event."

You might do well, too, at this point to coax your husband beyond the traditional male definition of sex as performance art. Intercourse, for example, no longer has to be the main course; mutual masturbation or oral sex are good substitutes on occasion. Even frequency, once the benchmark of male potency, is now negotiable. "When I was 30, I could get off four or five times a night," says Richard, 44. "There's no way I could do that now. But the orgasms are longer, more powerful, and more satisfying, so I don't desire them as often." Bottom line: While sex in a man's earlier years can be gratifying on a purely physical level, now enjoyment depends on love, commitment, and the intimacy that grows from years of exclusive experience.