The tale of 4 diets: here's what happened when we put four popular diet programs to a month-long test. Is one plan right for you? Check out the assessments of each diet from our test drivers and our nutrition expert - Product/Service Evaluation

BODY FOR LIFE

by Bill Phillips (HarperCollins, 1999)

A best-seller for a few years now, Body for Life is based on the concept that you can "transform your body and life in as little as 12 weeks." The book offers a complete diet and exercise program, along with plenty of commentary from author Bill Phillips, whose extremely motivational style is sure to inspire readers. Also included are impressive before-and-after photos (along with heart-touching success stories) of real people who have entered and won his 12-week body-transformation contests.

Who Tried It: Devin Alexander, 31, MUSCLE & FITNESS editorial assistant

Her Goal: To lose those last (and very stubborn) 15 pounds and find that six-pack

DEVIN'S REVIEW:

I first followed the Body for Life (BFL) program a few years ago, and it definitely worked for me then. This year I tried it again but didn't have the same positive experience; it actually turned out to be a backward step.

The first time, I didn't follow the plan to the letter I didn't have a cheat day, as the book recommends, but every week or so I intermittently indulged in a cheat snack That assured me that if I truly craved a treat at any given time, 1 could have it.

I think one major downfall this time was having the scheduled cheat day each week That set me up for failure. I occasionally eat chocolate, and because I know it's allowed, I don't have it very often. But committing to a cheat day and promising to not eat chocolate on any other day sent me into a total diet-and-deprivation mentality. I struggled not to have any chocolate during the week; when it came to Sunday, I ate lots of chocolate (and a lot of other foods I wouldn't normally eat). My head said, Well, you better eat it now, 'cause what if you start craving it tomorrow?

From calculating the exact amount of time between each rep in the gym to eating six meals a day, I found the program too regimented for my current situation. I just wasn't feeling like a normal, healthy, functioning woman.

I was disappointed to find that I didn't undergo a significant transformation by following the BFL program this time around. Perhaps it's because I was already working out and eating fairly healthy, so the program wasn't a huge shift from my current behavior Yet I firmly believe that anyone who hasn't yet joined a gym, or finds that the only jogging she's motivated to do is past the fast-food joint on the comer would definitely benefit from following this plan. It can be a great kick-start into a transformation that will motivate her to adopt an active, healthy lifestyle.

PROFESSIONAL PERSPECTIVE

SHERI BARKE'S REVIEW:

What Works? The program starts with honest personal reflection -- a deep look inside yourself to determine if you are truly ready to change and why. It then encourages participants to write very specific goals for themselves, anticipate old patterns of action that may hold them back, and plan for new patterns of action that will help them succeed. This type of inward reflection is critical for long-term behavior changes.

The Body for Life exercise plan focuses on quality, not quantity, and emphasizes the importance of rest (and not overtraining) for optimal results. It includes a realistic amount of both aerobic exercise (20-minute sessions of intense interval training, three times per week) and resistance exercise (about 45-minute sessions of intense weight training, three times per week).

The Body for Life eating plan is low in saturated fat; emphasizes high-quality, high-fiber carbohydrates; includes plenty of vegetables; and requires six small meals per day (each containing a balance of carbohydrate and protein) to keep metabolism revved up and stabilize blood sugar, insulin and hunger levels. Total calorie intake on the plan isn't too restrictive, consisting of about 1,800 calories per day.

What Doesn't Work? The book repeatedly states that being "physically fit makes you mentally fit." While this is true to some extent, it's dangerous to promote exercise, diet and physical fitness as the keys to emotional well-being.

Many people develop disordered eating and compulsive exercise behaviors because they falsely believe that if they can just lose weight or build muscle, they'll be happy Of course, this isn't true. Happiness comes from within. Even more worrisome, the book suggests that your physical body defines your self-worth and your success in life.

Before readers start the program, Phillips asks them to establish bodyweight, fat and/or muscle goals to measure their progress in physical fitness and life. While some people will see drastic body changes in a 12-week period, others won't, depending on genetics, bodytype, and previous eating and exercise patterns. But the book shows you only the drastic results, not the typical results (and certainly not the "failures").

This could set many readers up for disappointment, self-loathing and giving up. For lasting motivation and behavior change, it's better to focus on behavioral goals -- which we can always control -- and metabolic changes in physical fitness and health, which will always appear within a 12-week period.