LOS ANGELES -- Kourtney Kardashian makes gearing up for bikini season look so darned fun and easy. In Life & Style magazine, she explains that she drinks a lot of water, works out with 2-pound dumbbells (while wearing a fun leopard-print T-shirt) and has dropped her chai lattes in favor of espresso shots to save calories.

If you believe the glossy magazines that insist this is what it truly takes to drop 10-20 pounds and deflate your muffin top in time for summer, we've got a timeshare on the Gulf we'd like to sell you.

The reality? Brace yourselves for several weeks of sacrifice and deprivation, beginning with working out six days a week, twice a day -- yes, twice -- in a demanding routine of cardio and strength training. Add to that a diet regimen that leaves little room for cupcakes. And those two post-work glasses of wine? Don't think about it.

"Some people have an unrealistic expectation of what getting into shape for summer really entails," says Fred Engelfried, a trainer at the Sports Club/LA. "They think that working out three days a week is going to make that happen. The truth of the matter is that to take off 2 pounds per week, people need to be consistent across the board."

Diet is where most people get derailed, despite their best efforts, says Kara Mohr, an exercise physiologist and co-owner of a nutrition and fitness facility in Louisville, Ky. "People will say they're doing everything they can, but it's always the little nibbles here and there that get them, since they don't realize how much those things add up."

Mohr recommends eating 1,200-1,500 calories a day. That little blueberry muffin you had for breakfast has about 400 calories, or one-third to one-fourth of your total daily calories. It's also guaranteed to provide a nasty blood sugar crash later, prompting a binge on more empty calories. If you eat more foods with bulk and vitamins (i.e. fruit and oatmeal), you won't be starving or nutritionally bankrupt.

Most dietitians and nutrition experts suggest planning meals that include copious fruit and vegetables (without added sugar or butter), lean proteins (which provide a feeling of satiety) such as fish and chicken, low-fat or nonfat dairy, and healthful fats such as avocados and nuts. Whole grains are better than refined, but watch portions. Bread, pasta and cereals can quickly bump up calories.

Mohr advises weighing and measuring food cooked at home to make sure serving sizes don't creep up. A typical serving of protein should be 2 to 3 ounces, or the size of a deck of cards -- not the size of a shoe, which is what most restaurants provide.

Keeping a food diary is another smart way to spot trouble zones, such as mindless snacking while watching TV. This can be done with phone apps that track calories.

Eating small meals every three to four hours keeps blood glucose levels elevated so the body burns fat, not muscle, for energy, says Engelfried. Snacking on complex carbs and protein before exercising will keep the metabolism high and provide workout energy.

But it's going to take a will of steel to refuse the goodies that tempt us daily. Scheduling one splurge day per week is allowed, but don't go overboard: Have a reasonable amount of whatever you're craving, then get right back on track.

The exercise part of this process is just as rigorous. Plan to work out six days a week, and break those into two daily sessions, if possible, 30 minutes to one hour maximum each.

"By doing that, your heart rate will stay more elevated and you'll burn more calories throughout the day," says Mike Donavanik, a Beverly Hills, Calif.-based trainer.

Trainers recommend doing both cardio (five to six days a week) and strength training (two to four days a week). If exercise hasn't been in the picture for a while, start slowly and build up. Doing too much too soon increases the risk of injury and illness. Most cardio sessions should be done at moderate to intense levels.

Incorporate interval training two to three times a week, alternating between short bouts of moderate- to high-intensity exercise in the same workout. This supplies a whopping calorie burn and improves the cardiovascular system. A heart rate monitor makes it easier to distinguish between various workout zones, erasing any guesswork.

For strength training, doing a circuit of functional exercises that targets numerous muscles elevates the heart rate and produces lean, toned muscles -- the kind most women want to show off on the beach. Engelfried suggests starting with a 10-minute cardio warm-up, then doing a series of several minute-long multifunction exercises.

Taking a rest day and getting enough sleep are crucial for letting muscles repair.

If you find your motivation flagging, being beholden to a trainer, even once a week, can keep enthusiasm high. So can joining a boot camp, where the emphasis is on constant movement. The countdown to summer shouldn't all be drudgery. Engelfried advocates mixing up solo workouts with group classes.