Awesome Ab Blaster: Intermediate/Advanced
Bob Harper: Totally Ripped Core, $15, mytrainerbob.com
What you'll need: a pair of 3- to 5-pound dumbbells
Calories burned: 380 during a 48-minute routine, 65 during an 11-minute bonus*
The skinny: Testers loved the "fun mix of fast-paced core exercises," like weighted side crunches, and muffin-top-melting plyometric bursts from The Biggest Loser's master motivator. They also gave a thumbs-up to the on-screen countdown clock; it helped them push through the full routine, which made one reader "'good' sore every time I completed it." Finish with the stretchy bonus session, which includes trunk rotations and windmills.
Personal Training with Jackie: 30 Day Fast Start, $15, amazon.com
What you'll need: a pair of 3-pound dumbbells, a pair of 5-pound dumbbells, a yoga mat
Calories burned: 132 to 137 per 24-minute routine
The skinny: Nonstop supersets of sculpting moves "definitely make you feel the burn." Start with one rep of a biceps curl and then do one push-up. Keep adding another rep, alternating sets, until you've reached 10 reps of each. The two routines are split into an upper-body session and a lower-body and core combo. Celebrity trainer Jackie Warner's "encouraging" style will make you want to "do it over and over."
Mega Calorie Melter: Advanced
Amy Dixon: Breathless Body, $20, amazon.com
What you'll need: no equipment
Calories burned: 515 during a 55-minute routine
The skinny: "Breathless Body is definitely a fitting title" for Amy Dixon's cardio interval workout based on the Tabata method; it will have you "sweating during the very first drill." Crank out as many reps as possible of one move, like burpees or high knees, for 20 seconds, rest for 10 and repeat seven times before moving on to the next exercise. Three levels of intensity are modeled, so you can choose how turbo you go. The options inspired one reader to make "a goal of finishing the entire DVD on the highest level."
Best Trouble-Zone Tamer: Intermediate
The Bar Method Super Sculpting Workout, $20, barmethod.com
What you'll need: a pair of 2- to 4-pound dumbbells, a yoga strap, a 7-inch playground ball, a chair
Calories burned: 287 during 59-minute routine
The skinny: If you're looking for a bar workout or to go beyond your usual Pilates, try this head-to-toe toning session that's built on small, precise movements. The moves may "seem subtle" — you'll do one-inch lifts or squeeze a playground ball between your knees as a leg exercise, for instance — but "they really target the upper arms, thighs, and hips."
Perfect Circuit: Intermediate/Advanced
Jillian Michaels: Ripped in 30 $15, amazon.com
What you'll need: a pair of 3- to 8-pound dumbbells
Calories burned: 222 to 250 calories per 24-minute workout
The skinny: Jillian Michaels' winning formula? Strength-and-cardio sessions built on three minutes of toning (like alternating lunges with biceps curls), two minutes of cardio (speed skaters), and one minute of ab moves (elbow-to-knee planks). Follow one of four half-hour workouts each week from the "motivating," no-excuses former Biggest Loser trainer for a "sweat-tastic" routine. One new-mom tester found that "the quick workout options are perfect for burning calories during naptime or before work."
Kickboxing Champ: Intermediate
Billy Blanks: PT 24/7 $90, billyblankspt247.com
What you'll need: fingerless boxing gloves, resistance tubing (both included in DVD set)
Calories burned: 269 to 309 per 30-minute disc
The skinny: "Charismatic" martial arts phenom Billy Blanks is back with Tae Bo 2.0. You'll feel as if you "really accomplish something in 30 minutes." Besides the "inventive" bands and gloves that add resistance to each workout, the kit comes with a nutrition guide and a calendar suggesting which of the seven workout discs to pop in so you "don't have to think about which to do next."
Total-Body Time-Saver: Beginner/Intermediate
10 Pounds Down: Better Body Blast $15, amazon.com
What you'll need: a pair of 5-pound dumbbells, a yoga mat
Calories burned: 62 to 189 calories per 20-minute routine
The skinny: Choose from three 20-minute target-toning routines — arms, abs, legs — which are "easy to fit into a busy schedule," or do them back-to-back for a "megaworkout." Alternate between "killer" strength exercises, like side lunges with knee raises and kickboxing-inspired cardio blasts that "keep my heart rate up." Trainer Jessica Smith offers "many variations I've never seen before," such as an on-all-fours bicycle crunch.
Yoga Master: Beginner/Intermediate
Shiva Rea: More Daily Energy $20, acacialifestyle.com
What you'll need: a yoga mat
Calories burned: 173 during 65-minute "lunar" routine, 227 during 85-minute "solar" routine
The skinny: Expect a gentle mat session from the longtime yogi and rock star of asanas, Shiva Rea. Broken down into mix-and match 7- to 20-minute segments, this "meditational" yoga workout is "perfect for days off from cardio" and "helped me feel less sore after my other workouts." The sequences "get the kinks out of your neck and back" after a long day at the office.
Best Boredom Buster: Intermediate/Advanced
Cathe Friedrich: Slide & Glide $23, shop.cathe.com
What you'll need: a pair of gliding disks or paper plates, a resistance band loop, a yoga mat
Calories burned: 346 during 52-minute routine
The skinny: Get a "superb workout without the impact" thanks to "unique" strength and cardio moves using gliding disks (or paper plates on a carpeted floor). The "quick pace" and upper- and lower-body combination moves, like squat thrusts, use gliders under your feet so you slide rather than jump. Workout DVD veteran Cathe Friedrich even incorporates gliders in an ingenious cool-down that allows you to "slide past your sticking point" during stretches.
Lower-Body Transformer: Intermediate/Advanced
Tonique Mat Workout $19, amazon.com
What you'll need: a yoga mat
Calories burned: 63 to 101 calories per 17- to 27-minute routine
The skinny: These three butt- and leg-firming workouts are efficient — just 17, 22, and 27 minutes long — as they'll max out your muscles with high-repetition on-the-mat moves, like bridges and donkey kicks. They had one tester swear, "I think I'm still burning!" well after the workout ended. Instructor Sylwia Wiesenberg makes the routine "seem effortless," but one tester bets you "can't finish without taking a break." It's worth the effort: "If you stick with it, you'll look and feel great."