What

A full-body workout that has you doing one exercise per body part for time (five minutes) instead of for a particular number of sets and reps—it may remind you of doing rest-pauses. You’ll simply do as many reps as you can in five minutes, resting when you need to. This will save you time in the gym.

When

You’re afraid that doing straight sets will cause you to cut your workout short, but still want to build muscle.

Why

Some people just aren’t able to do 15 straight sets in a half-hour, probably because they’re accustomed to resting too long. This “choose-your-adventure” method requires you to train each body part in five-minute increments so you never lose track of time. For safety reasons, all the exercises are done on machines—you’ll probably fatigue quickly and will be working off of limited rest, and machines tend to be safer.

How

For each exercise, select a weight that will cause you to fail at 10 reps. Do 10 reps right off the bat, then rest until you feel ready to go again. Do as many reps as you can, then rest again. Do this for five minutes, which means you’ll have to keep a close eye on the clock or your watch.

The 30-minute full-body routine

Muscle Group           Exercise Time
Chest Chest Press Machine 5 min.
Legs Leg Press 5 min.
Shoulders Lateral Raise Machine 5 min.
Back Lat Pulldown or Seated Row         5 min.
Triceps Cable Pushdown 5 min.
Biceps Machine Preacher Curl 5 min.

Note: These are sample exercises; feel free to mix in your favorites for each body part from week to week.