While Sarah receives most of the blame for getting mankind kicked out of paradise, it should be mentioned that she was duped: God never told her about no stinkin' forbidden fruit. Adam, on the other hand, knew exactly what he was doing and knew it was wrong. Downside: Kicked out of the Garden of Eden. Upside: Finally realized Eve was naked.

Not all temptations have consequences of this magnitude. In fact, some might even be good for you. Consider this your temptation bible—a guide to the good, the bad, and the downright damnable.

Skip Your Workout

Indulge

Go ahead, take a few days off. In fact, take the whole week. If you've been working out seriously—three or four times a week, regularly for 6 to 8 weeks—a break might be just what your deltoids ordered. "Then go back with a totally different workout," says Eddie Carrington, fitness director at Bally's Total Fitness. "It will shock your muscles, building them faster." Don't avoid exercise altogether, though: Some light cardio—biking, running—will keep your muscles engaged.

Have a Candy Bar at Lunch

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"If you just want to tide yourself over for an hour, fine," says Dave Grotto, R.D., director of nutrition education at Block Medical Center, in Evanston, Illinois. "But a candy bar can't substitute for real food." It will cause your blood sugar to spike, Grotto says, which will spark the overproduction of insulin, which will cause your blood sugar to plummet, which will leave you hungry and cranky—right where you started. Instead, grab an energy bar. We like LäraBar, with fruit and nuts providing the right mix of carbs, fats, and protein to keep blood glucose stable until your next meal.

Read Her Diary

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What is it you're hoping to find out, exactly? Because chances are, you already know. Actively seeking to uncover her private thoughts—and this includes hacking her e-mail—is an indication that there are larger issues in your relationship, says Michael Nuccitelli, M.D., director of SLS Health, in New York City. "Often, the guy's keeping a secret from her," he says, "which makes him wonder if she has secrets, too." So put down the diary, find your girlfriend, and talk to her. It's a sign of a mature relationship. But don't let that discourage you

Tell a Friend What His Problem Is

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Can't stand another night with Charlie because he's a jerk when he's drinking? Don't be shy. "Part of being a friend is offering constructive criticism," says Dr. Nuccitelli. It's win-win: Either he takes your words to heart and shapes up, or he quits calling you.

Gossip About the Boss

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But be careful. "Unload to one person at a time, and only to someone willing to unload back," says Gil Schwartz, Men's Health's in-house career consultant. "Then you'll have as much on him as he does on you." Avoid complaining to people above your level, even if you think they agree with you—it's a sign of disloyalty. And if you're caught—well, don't get caught. "Bosses need to trust their people," says Schwartz. "Once that trust is broken, you're screwed."

Pop a Pill to Help You Bulk Up

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Unfortunately, as with small-business ownership, good help is hard to find. Look for a supplement that increases protein synthesis and stops protein breakdown, says Christian Finn, founder of factsaboutfitness.com. "Think of your muscles as a bathtub," he says. "Water coming in represents protein synthesis. Water draining out stands for protein breakdown. When there's more water coming than going, you end up with bigger muscles." Creatine, whey protein (take it pre workout), and protein-carb supplements like Mass Factor (after a workout) will all keep your tub full.

Play Hooky

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"Sometimes you need a day off to reenergize," says Scott Sindelar, Ph.D., a psychologist in Scottsdale, Arizona. How will you know? If you like your job but dread going to work today, call in sick. Don't, however, use a sick day to avoid tackling a big project—you'll just fall another day behind and feel even worse. Instead, says Sindelar, reward yourself after you've completed a big project. And don't worry that the company will burn to the ground without you. You're good, but not that good.

Pee in the Shower

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Remember that guy in college who told you urine is the cleanest fluid in the human body, then relieved himself in the stairwell? That guy was a liar. "Urine is not sterile," says Charles Gerba, Ph.D., a professor of microbiology at the University of Arizona. "It carries viruses and bacteria that can be passed on to other people." But if you don't have any roommates or romantic prospects, go ahead, whiz kid.

Have Sex with Your Ex

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You're both horny. You're both easy. Go crazy. Then stop. "If it happens more than a couple of times, chances are emotions will kick in—either yours or hers," warns Lou Paget, a sex educator and the author of The Great Lover Playbook. If your ex calls you a couple of times a week—even just to say, "Thanks for the meaningless sex"—it's time to bail.

Tell a Guy His Wife is Cheating

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But only if the guy in question is a family member or your best friend, says Dr. Nuccitelli, ruining the fun. "Those people are your family," he says, "and adultery can rip a family apart." With an acquaintance or a coworker, he says, there are too many unknowns: Do they have an open marriage? Have they quietly separated? 

When it comes time to rat, sit the guy down, let him know you have serious information, and gently present the evidence. "If he accuses you of lying, don't fight it," Nuccitelli says. "The seed's been planted, and eventually he'll face the facts."

Tell Off the Boss

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Would you defecate on your résumé before submitting it to HR? Fact is, your clever analogies and cunning wit aside, your boss is your ticket to the future. He also has more corporate capital than you do. So even if you land a few verbal jabs, he'll win by technical knockout every time. Then there's this: "A lot of industries are small," says Tom Markert, author of You Can't Win a Fight with Your Boss. "Apply for a job at a competitor and your old boss might be the first person they call."

Check Your Fantasy Team Scores

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The human brain can process only about 30 to 45 minutes' worth of information at a time, so a 5- to 10-minute break every hour might boost your productivity. That said, if you spend the majority of your pre lunch hours logged in as Super Slugger 01, it's time to reprioritize. "Identify the triggering event," suggests Alan Manevitz, M.D., head of the psychology department at Cornell. If you always log on after lunch, schedule meetings for 1:05. "Or, instead of trying to quit cold turkey, stop between 2 and 4 p.m.," he says.

Pad the Expense Account

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Eventually, says Markert, everyone has an expense report audited. "I've seen people lose their jobs over $20," he says.

Borrow from Your 401(k)

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First, unlike with your original contribution, you'll repay with after-tax money. "That means you'll have to make $7,000 to pay back $5,000," says Robert Brokamp, editor of the Motley Fool Rule Your Retirement newsletter. Second, even though you're borrowing your own money, you have to pay yourself back with interest, cutting into your disposable income. Finally, and most important, the borrowed money will stop growing: Withdraw 5 grand at age 35 and you'll reduce your retirement nest egg by $100,000. 

The only valid reason to tap a 401(k) is for the down payment on a first house. The tax savings from mortgage interest, and the equity you'll build, may compensate for the retirement losses.

Sit and Watch TV All Day

Resist

Sure, you deserve a relaxing weekend, but TV has the opposite effect. "Anytime something shifts in our visual environment, it triggers an orienting response in the brain," says Sindelar. "So TV keeps our brains constantly alert, which is why many people are tired and irritable after a couple of hours." The best approach: Find a show and put the remote across the room. When you get up to change the channel—and you will—it'll break your visual connection with the TV and silence its siren song. Then go do something useful.

Order Hot Wings at Dinner

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If you've been eating well all week, some greasy goodness on Friday night won't explode your waistline—or your heart, for that matter. "But get back on track on Saturday, or you can ruin a week's worth of healthy eating," warns Heather Bainbridge, R.D., a dietitian with the Comprehensive Weight Loss Center, in New York City. Be extra careful if you wash the wings down with a few MGDs. "Your body will metabolize the alcohol first," Bainbridge says, which will dehydrate you and increase your appetite.

Go to Bed Without Brushing

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You're alone. You're exhausted. You just can't stand the thought of a mint gum scrub. Go to bed. "A good dose of vitamin S—sleep—is helpful in warding off gum infection," says John Coke, D.D.S., an associate professor of dentistry at the University of Alabama. In today's fluoridated world, gum infections are as big a health threat as cavities.

Sleep with 2 Women

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Of course, indulge. But a word of warning: "When men actually live out this fantasy," says Paget, "it's often nothing like they expected." So, before a stitch of clothing is shed, cover your ass: Find someone you and your partner can trust, but not someone either of you knows well or is likely to run into at church. Before the evening begins, agree on what (and whom) everyone will and will not do, and how long the encounter will last. Finally, be prepared for your partner's reaction, which could range from sheer disgust to "girls rule." How to know what type of woman she'll go for? Read her diary, of course. (Just fucking with you.)

Smoke a Fine Cigar

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But you'd better have a good reason, like to celebrate a birth, a promotion, or that threesome. Smoking a cigar twice a year isn't much worse than sitting in a smoky bar twice a year—it won't do any cumulative damage. That said, if you kicked the habit years ago, you're asking for trouble. "Smoking can lead to permanent changes in the brain," says Epi Mazzei, R.N., a cessation specialist at the National Jewish Medical Center, in Denver. "Once you quit, the nicotine reward pathways still exist. Smoking can activate those pathways and cause the cravings again.