1.) Shorten Rest Periods
Shaving seconds off your rest period can help to raise your metabolism greatly. Just don’t go too low, you need a minimum of 30 seconds’ rest or you risk burning out. The one exception is circuit training, which requires no rest inbetween sets.
3.) Alternate Sets.
Do a set of a lower-body exercise followed by an upper-body one, such as performing a squat and then a row. This way, one muscle group has time to recover while you train another one.
4.) Increase Lifting Speed.
You can burn more calories by doing explosive exercises like plyo pushups (where you push yourself into the air) and box jumps, or by using lighter weights and lifting them more explosively on the upward phase of the movement.
5.) Decrease Reps.
Most guys’ workouts are based around the idea of 10 reps per set. But according to Jim Smith, you can get a much bigger spike in metabolism by reducing your reps and tacking on an additional set. Try sets of six to eight reps.