45-Minute Circuit Workouts

Exercise Selection

Choose compound exercises that work multiple muscle groups simultaneously, such as squats, lunges, deadlifts, pushups and rows. These workouts give you much more bang for your buck, claims strength coach Nia Shanks. They hit more muscle fibers, burn more calories and elevate your metabolism more than isolation exercises. Don't waste time with biceps curls, triceps pushdowns or leg extensions. (See Reference 1)

Equipment

Barbells, dumbbells, machines and even your own body-weight are effective tools in circuit training, so it's worth experimenting to find what you enjoy training with. Choosing equipment does not come with rules, but you want to be able to switch quickly between exercises. Don't try to use too much equipment for one single circuit either; a circuit that comprises work with a barbell, two sets of dumbbells, a kettlebell, six medicine balls, three weight machines, a sandbag, rowing machine and a resistance band may be pretty tough and enjoyable, but it probably won't endear you too much to other gym members. Combine strength exercises and cardio in your circuit if possible, as this burns more calories (up to 10 per minute) than strength training alone, according to Liz Neporent, author of "Fitness for Dummies." (See Reference 2)

Circuit Variations

Traditional circuits involve performing a series of exercises back to back with no breaks, then taking a short rest and repeating. This is all well and good, but you don't want traditional circuits -- you want super tough, super effective, fat-blasting circuits, therefore you need variation. Use timed circuits, where you set a timer for five, 10 or 15 minutes and complete as many rounds of a set circuit as you can, aiming to better your performance every session. Or try ladders; pick four or five exercises and perform 10 reps of each in round one. Go straight to round two and do nine on everything and keep going until you're down to one rep of each. If you are feeling adventurous and not completely exhausted, go back up to 10 again.

Progression and Programming

If you train the same, you stay the same. This is a phrase that many gym-goers fail to realize. Don't be like the girl who comes in every day and does the same workout over and over again. Set the example and push yourself to make changes. Always aim to improve your performance in every workout. You can do just one circuit in your 45 minutes, although that would probably get pretty boring, so you're best off designing two, three or even four different circuits and rotating through each one. Keep pushing yourself and always strive to leave the gym in a sweaty, quivering mess. It may not be pleasant, but it will keep that muffin top and those bingo wings at bay.