Most people who begin an exercise and diet routine are interested in two things: losing fat while also building lean muscle. One way to improve results in both areas at once is using circuit training in your workouts.
In circuit training, you will repeat a few different exercises in a particular order with a short rest in between exercises. The exercises you select, the amount of weight you use for each exercise and the number of sets and reps will depend on your current fitness level and individual goals, but here are some general guidelines for an effective circuit training routine.
Choose exercises that use as many different muscles as possible. This will require more energy and give you better, faster results than exercises only using a few smaller muscles.
Try to limit your rest periods in between exercises to 1 minute or less. This will keep your heart rate elevated to increase fat burn and act as a cardio workout while you weight train.
If your goal is to gain lots of muscle quickly, using very heavy weights and doing fewer reps will yield better results. Ideally, the weight should be heavy enough that you can do 3-6 reps with good form, but no more. For those who want to tone their muscles without bulking up, lower weights with a higher number of reps will be fine.
A full-body workout is ideal, but you can select particular exercises depending on your fitness goals. A good circuit will have between 3-8 different moves.