Many people struggle with planning a workout at the gym. Maybe you’re one of them. NASM teaches that there are two commonly used systems for a workout: horizontal loading and vertical loading. What are the differences, and which one works best for you?

Horizontal loading is most commonly used because it makes sense and is practical for busy gyms. Horizontal loading refers to doing all sets of an exercise in a row, taking rest periods between sets. Imagine a chart that lists your exercises from top to bottom, the columns that move left to right represent each set of the exercise. Horizontal loading would be doing all sets, moving from left to right – horizontally – on the chart, before moving to the next exercise.

An example of this would be to start your workout with bench press and complete all sets before moving on to your next exercise. Then you do the same for each exercise until your workout is done.

This system works best for people who are looking to make strength and muscle size gains and for people who have more time to workout. It takes longer to get a full workout using horizontal loading because you are working one muscle group at a time, which means you will need longer rest periods to recover between sets. If you are not careful, you can spend more time resting than working at the gym.

If you are looking to get the most out of your limited time in a gym and cut down on your rest periods, you will get more out of a vertical loading workout plan.

Vertical loading means doing one set of an exercise and then moving down your list of exercises — vertically — to the next one. An example of this would be completing one set of a dumbbell bench press, moving immediately into squat jumps, and then directly into shoulder presses, and so on until you’ve completed five or more different exercises. Then you take a short rest and do it all again.

Vertical loading is often referred to as circuit training. Circuit training keeps you moving your entire workout.

With circuit training, you’ll keep your heart-rate up, sweat more, and burn more calories.

Your exercises should alternate which body parts are being targeted. By the time you start your circuit again, your muscles will have fully recovered from the first set of an exercise. Vertical loading takes a little more planning and gathering necessary equipment before you start, but you’ll see great results and make the most out of your time in the gym.

A good workout can include both systems. I often start with my heavy lifting in a horizontal loading pattern, then switch to circuit training halfway through. By the end of my workout, I know I got the most out of my time in the gym.

Think about your workout plan the next time you hit the gym, and you may find a new plan of attack may be all you need to reach your goals.