The fitness industry is leaning (and bending, extending, pushing, pulling and twisting) towards functional training using integrated movements, rather than isolation exercises

In the majority of gyms and health clubs today, resistance machines commonly take up the lion’s share of the floor space. Indeed, if a potential member was to take a look around a gym without any fixed-path equipment, chances are they would want to go somewhere else ‘better equipped’.

But are machines the best way to achieve the fitness goals of most exercisers?

Free Weights Are In for Body Building

Ironically, resistance machines are relatively new in the fitness world. The book ‘Muscle Building’ by Earle Liederman, published in 1924, did not include a single exercise performed on a machine with a fixed axis of rotation (1). Resistance training back then was all about free weights. However it was also all about body building – it would be many years before the benefits of this form of training for general health, fat loss, injury prevention, etc, would be realised.

Body builders need to place as much load on each individual muscle group as possible in order to maximise hypertrophy (an increase in the size of a certain area). The force produced in any body movement is limited by the weakest link in the chain – therefore isolating a joint movement by keeping everything else still (or stable) means maximum force production of the muscle across that specific joint.

Cams and Pulleys

So it was in the 1970’s that engineers began to use cams and pulleys to make machines that isolated joint actions such as the Leg Extension and Leg Curl. The stability offered by these machines allowed a lot of weight to be lifted, and thus they became a popular method of resistance training.

However, there are some fundamental problems with this approach. A major one is that the body needs to distribute force across as many joints as it can during movement to protect itself. In gait (walking) for example, upon heel strike the ankle, hip and spine should move along with the knee to absorb some of the forces, and in fact, the movements at these joints will vary slightly with every heel strike. Similarly, if you review research on elite Olympic lifters, you will find that not only does the bar path change slightly each time they lift, no 2 lifters produce the same bar path when executing the same lift (2).

The use of slightly different paths in each repetition of a free weight exercise (or any natural movement for that matter) is due to the central nervous system’s recruitment of different motor units which both conserves energy and prevents something known as ‘pattern overload’(3). This occurs when segments of the body are immobilised, which deprives the body of movement options. Each and every repetition of an exercise becomes more similar (even identical), which means the same motor units are recruited. This can result in fatigue of the fibres of those particular motor units, reducing the dynamic (muscular) control over the joint during the movement. This then places excess strain on the passive support structure (ligaments and tendons) which can lead to injury.

We can see these unnatural restrictions occurring with the use of resistance machines, for example sitting down on a Leg Extension machine prevents the hip joint and spine from moving so that all the force from the exercise is directed into the knee.

To this day, despite the majority of the exercise population not being body builders, traditional training techniques still emphasise the isolation of body parts. For example, on the Seated Row gym members are taught to keep the chest against the front pad and remain seated so that only the arms move to extend the shoulders and flex the elbows

The Body Takes Control

Of course, people may often ‘cheat’ when performing these exercises, allowing their bodies to swing, or elbows to flare out to the sides. Is this really ‘cheating’, or just the body trying to move naturally in order to dissipate the loads being placed upon it? It is no coincidence that we can lift much more weight when we allow this force distribution!

In recent years, greater understanding of the true function of the human body has led trainers and researchers to favour whole-body, integrated movements as the basis for exercise. As the majority of exercisers want an injury/pain-free body that functions properly and looks good (usually without huge muscles!), ‘functional’ training achieves this goal much more effectively than traditional isolation training.

So now we see exercises devised around natural movement patterns, such as bending, pushing, pulling and twisting (an often neglected movement plane), all performed in a standing position with equipment such as dumbbells, kettlebells and cables, or just with body weight to replicate the dynamic forces that would act on the body in daily life.

REFERENCES:
(1) Liederman, E. Muscle Building. New York, NY: Earle Liederman, 1924.
(2) Roman, R.A. and Shakirzyanov, M.S. The Snatch, The Clean and Jerk. Published: Andrew Charniga Jr., 1982.
(3) Chek, P. Pattern Overload - Part One. PT on the Net, 2000