Compound vs Isolation Exercises: 5 Best Ways to Build Strength

In the world of fitness, vocabulary can often feel like a barrier to entry. You hear terms like “compound movements” and “isolation work” tossed around the gym floor, often accompanied by conflicting advice on which is “better.” At Pillar, we reject the idea that fitness is a battlefield where you must choose a side. Instead, we view your body as a laboratory.

To conduct a successful experiment—your workout—you must understand your tools. The choice between compound and isolation exercises isn’t about right or wrong; it’s about understanding the specific Stimulus you are trying to apply to your body to get a specific result.

Here is the science-backed breakdown of the difference between compound and isolation exercises, and how to use both to design the perfect hypothesis for your training.

Table of Contents

Compound Exercises: The Primary Stimulus

Compound exercises, often referred to by researchers as “multi-joint” exercises, are movements that require more than one joint to move and more than one muscle group to work simultaneously. Think of the squat: your hips, knees, and ankles all articulate at once, requiring your quadriceps, hamstrings, glutes, and core to fire in unison.

Because they recruit so much tissue, compound exercises are generally the most efficient way to apply a massive stimulus to your system. They are the “big rocks” of your training protocol.

The Efficiency Advantage

When designing your workout hypothesis, you often face the constraint of time. This is where compound movements shine. Research published in Frontiers in Physiology compared groups performing multi-joint exercises against those performing single-joint exercises with equal total volume. The study found that while both groups improved, the multi-joint group saw significantly greater improvements in maximal oxygen consumption (VO2max) and strength (1).

If your goal is to maximize the systemic impact of your workout—burning more energy, improving cardiovascular health, and building overall strength—compound movements provide the highest return on investment.

Examples of Compound Exercises

Squats (Hips, Knees, Ankles)
Deadlifts (Hips, Knees)
Bench Press (Shoulders, Elbows)
Pull-Ups (Shoulders, Elbows)
Lunges (Hips, Knees, Ankles)

Isolation Exercises: Targeted Adjustments

Isolation exercises, or “single-joint” exercises, involve movement at only one joint and primarily target a single muscle group. A bicep curl is the classic example: only your elbow moves, and the tension is placed almost entirely on the biceps.

In the Pillar Methodology, we use isolation exercises not as the primary driver of progress, but as precision tools for “fine-tuning” your experiment. They are essential for the Audit process. If you identify a specific weak link or a muscle group that isn’t responding to the primary stimulus, isolation exercises allow you to target that specific variable without fatiguing the rest of your body.

The Equalizer for Hypertrophy

There is a common misconception that isolation exercises are “useless” for growth. However, science tells a different story. A 2015 study found that when looking at specific muscle growth (hypertrophy) in the arms, isolation exercises were equally effective as compound exercises (2) at increasing muscle size in untrained men.

This means that if your specific goal is to grow your biceps, you don’t have to rely solely on rows or pull-ups; direct isolation work is a valid and effective tool.

Examples of Isolation Exercises

Bicep Curls (Elbows)
Tricep Extensions (Elbows)
Leg Extensions (Knees)
Hamstring Curls (Knees)
Lateral Raises (Shoulders)

Designing Your Protocol: The “Stimulus” Mix

So, how do you combine these into a coherent plan? You form a hypothesis based on energy management.

Compound exercises require a high neural drive and significant energy resources (Nourish). Because they tax the entire system, they should generally be placed at the beginning of your workout when your energy is highest. This ensures you can perform these complex movements safely and with sufficient intensity.

Isolation exercises are less systemically fatiguing. They are best placed toward the end of your session to fully exhaust specific muscles or to work on weak points identified during your Audit.

A Simple Framework

Primary Stimulus (Start Here): 1-2 Compound movements (e.g., Squats, Overhead Press).
Secondary Stimulus (Follow Up): 1-2 Accessory compound movements (e.g., Lunges, Rows).
Targeted Adjustment (Finish Here): 1-2 Isolation movements (e.g., Calf Raises, Bicep Curls).

Conclusion

Your body is a laboratory, and every exercise is a variable you can manipulate. Compound exercises are your primary tools for systemic change and efficiency, while isolation exercises are your precision instruments for specific growth and correction. There is no guilt in choosing one over the other—only data to be gathered. Use both wisely to build a sustainable, evidence-based protocol that evolves with you.

Compound vs Isolation Exercises: The Science of Efficient Training