The core of this game is its very comprehensive list of dozens and dozens of "Single Exercises", which are essentially old-school calisthenic exercises (i.e. exercises that don't use weights or equipment). Every exercise imaginable is included, including exercises for cardio, upper and lower body, core, and even yoga poses. Each is clearly identified by an icon and color-coded by intensity (light, moderate, challenging, hard, and intense). As you select each exercise, there's even a diagram telling you exactly what muscle groups you're working out.
During each exercise, an on-screen figure will demonstrate to you very clearly how to do it, including the correct posture, moves, and timing. The exercises typically use the Wii-mote and/or the Balance Board to passively "check" your progress in different ways. For example, when you choose the jump rope exercise, you hold the Wii-mote like a jump rope and make small circles with it. With "tire drills", you put your Wii-mote in your pocket and the system registers the vibrations as you run in place rapidly. There are a number of exercises which use the balance board such as the "plank" (where you press both hands against the balance board) and the "T-raise" (where one hand is on the balance board and the other is stretched out). Some exercises will be very familiar (jumping jacks, push ups), but even the ones that aren't familiar are very intuitive once you watch the on-screen character doing them.
You can do each of the exercises a la carte, but more likely you'll want to choose "Exercise Routines", which combine multiple single exercises into comprehensive pre-designed programs. You can also create custom routines.
You can also choose the full "Fitness Program". You enter your vital information (conveniently, you can use your Balance Board to measure your weight, both your initial weight and in your very own "weigh ins"). Then, you pick your favorite real-life Biggest Loser contestant to play as from a list of eight past contestants. You can pick whether you want Bob Harper or Jillian Michaels as "your trainer". From there, you can pick a personal goal: whether you want to simply maintain your current weight and improve your health, lose a little weight, or lose a lot of weight. You'll also pick a skill level and a program length.
Based on what you enter, the system will calculate a specific exercise regimen for you, complete with dates. If you're really committed, you can also input the number of calories you eat every day, as well as log any additional training you do outside of the program (such as walking, running or biking outside), and the program will adjust itself accordingly.
An interesting part of this title is a menu option called "Health and Lifestyle". Here, you'll find a large number of recipes straight out of The Biggest Loser Cookbooks. Under this menu option you'll also find a large number of "quick tips" from past Biggest Loser participants, including short video clips from Bob and Jillian themselves. Finally, there's an extremely useful feature called the "Calorie Counter", which calculates the daily calorie intake recommend specifically for you based on your weight, age, and goals.
The most interesting part of The Biggest Loser for Wii are what they call "Challenge Events". Here, your on-screen character will compete in a number of interesting events, the types of which you'd see on the show. As on the show, you start out competing with 7 personalities from the show, and after each round one is eliminated. You don't actually simulate the movements of the character on screen, but instead you perform "single exercises", and your character does his task only if you do the exercises precisely and timed correctly. I found this by far the most effective part of the game, because my instincts to compete far exceeded any resistance to exercise.
There are a couple minor annoyances. If your balance board power goes out, the game is completely hung up until you turn it back on. The controllers are passive, meaning that instead of actively tracking your movements accurately, it'll just check whether you come close to making the on-screen movements. Sometimes the controllers will not register properly, and in many cases, you're on the "honor system" as to how closely you follow the on-screen examples (even if you get a little sloppy in your form or don't do the exercise properly, Bob or Jillian may continue to shout out praise and encouragement). One thing to keep in mind is that you need a LOT of room to move around. And I admit I was a little disappointed that most of the activities didn't take advantage of the unique capabilities of the Wii and its controllers in the same innovative ways that Wii Fit Plus does--at the end of the day it's really not much more than a glorified exercise video.
But still the bottom line is, they have an impressive number of fundamental exercises to work out all different areas of your body. When I choose "intense" level in particular, it really does make my heart pound and gives me a great workout that rivaled any kind of workout I'd get at the gym, for a fraction of the price. And fans of the TV show will appreciate the details like the voice talent, the familiar settings, Bob and Jillian's coaching, and the recipes and tips.
Bottom line, if you're looking for something along the lines of a more traditional exercise video, or you're a die-hard fan of the show, you won't be disappointed. If you're looking for something that's a game first and exercise second, try something else like Wii Fit Plus or Dance Dance Revolution.