Alternate lower- and upper-body exercises without rest in between to up your caloric burn. Moving quickly from squats to biceps curls, for example, can raise your heart rate by forcing blood to shunt from your legs to your arms.
2. Drop the Weight
Squeeze every ounce of effort out of your muscles with drop sets This technique recruits more muscle fibers for faster results. Start with a weight heavy enough to fatigue muscles in 10 reps. Use a slightly lighter weight for a second set. Then go even lighter for a third set (for example: 15 pounds to 12 pounds to 8 pounds).
3. Work Two Muscle Groups at Once
Save time and burn more calories with a series of compound-body moves targeting several muscle groups together. Try adding bicep curls to squats or lateral shoulder raises to lunges.
4. Balance on One Leg
Using one foot instead of two during strength moves will recruit the muscles in your core, helping you sculpt flat, ripped abs. Stand on one leg for everything from tricep extensions to squats. Because you have to work harder to maintain your balance, you may need to use slightly lighter weights with this technique.
5. Team Up on One Muscle
Tone your most stubbern parts into shape by doing back-to-back exercises for the same muscle group. For example, blast your legs with lunges followed by squat jumps. To attack your abs, do bicycles followed by reverse crunches. This pushes your muscles to fatigue.