Compound vs. Isolation Exercises

15 August 2017 2 min read

What is the difference between compound and isolation exercises?

Basically, two types of strength exercises can be distinguished: single-joint and multi-joint exercises, or as you often hear, isolation and compound exercises.

With single-joint exercises, also called isolation exercises, the movement happens across only one joint (e.g. the knee joint). With multi-joint exercises, also called compound exercises, the movement happens across several joints (e.g. the knee and hip joints). Two examples are shown below.

Single-joint exercises target fewer muscles, but more precisely. They are therefore more intense. The exercises are easier to learn because the demands on coordination are minimal. In this respect, they are well suited for beginners. Multi-joint exercises work the muscles of a muscle loop at the same time. The movement sequence is therefore somewhat harder to learn.

Are compound exercises more effective than isolation exercises?

Because the individual muscles of the muscle loop have different strength curves, the cam in compound exercises or multi-joint exercises is “only” effective for two thirds of the range of motion. This is because multi-joint exercises exert an almost straight (linear) pressure and therefore do not apply resistance directly the way single-joint exercises do. The advantage of multi-joint exercises is the so-called spillover effect (indirect training effect). This effect describes the observed strength gain in the surrounding muscles that are not directly trained when training large muscle groups such as the glutes and thigh muscles. However, this effect is more likely to be observed in beginners.

For building up individual muscle groups, isolation exercises are therefore better suited, so compound exercises are not the first choice.

More testosterone from compound exercises?

You often hear that it is better to first train the large muscle groups with compound exercises and then the small muscles with isolation exercises. The supposed reason is that compound exercises produce more testosterone. The higher amount of testosterone then leads to more muscle growth throughout the whole body.

Compound exercises do indeed lead to a short-term increase in testosterone production. However, the testosterone level after training is roughly the same as it is in the morning after getting up. This amount is therefore not enough for better effects on muscle building!