As a personal trainer and muscle activation technique specialist, my job is to keep my clients loose and flexible. Mobility and flexibility are integral part of any personal training program.
In order to achieve this, a good personal trainer would ensure that the training routine he/she designs is well balanced. When a training routine is well-balanced, muscle groups and movement chains are equally stressed. On the other hand, if one particular movement chain or muscle group gets overstressed, the nervous system will make an attempt to protect it by tightening the opposing muscle group. A good example of such phenomena is a guy at the gym that bench press 3-4 times a week, often to muscle failure. The body quickly learns that priority must be placed on the ability to press allot of weight at all cost. As a result, his posture will alter in response to the stress by shifting the shoulders forward. This shit can help him gain strength but this is often at an expense of stiff neck, poor shoulder mechanics and even pain at the lower back. Continual stress in such posture can yield more serious injuries, like a rotator cuff tear.
In the following article I will explain one the most important principles of a well-balanced personal training routine- planes of motion. I will also explain how planes are often be used by a personal trainer as a variable in an exercise routine.
Planes of Motion
Plane of motion refer to the direction your body, or limbs, are moving in. The three planes our body can move in are; segital, frontal, and transverse.
Segital plane. Segital plane refers to a front to back movement. An example of segital plane exercise would be a squat (fig 1). If you look at the squat all joints move either forward or backward.
Frontal plane. Frontal plane refers to a side-to-side movement. A good example of frontal would be standing hip abduction exercise (fig 2). One leg is moving to the side and the other leg is stabilizing in the same plane (interestingly, most personal training clients feel the burn on the standing leg more than the moving one).
Transverse plane. Transverse plane refers to rotational movements. A quadruped trunk rotation is a good example of rotational movement (fig 3). The axis of movement goes through the spine as illustrated. The axis represent a pivot around which the torso rotates about.
Planes of Motions as an Exercise Variable
These planes provide as an excellent exercise variable and are commonly used by a personal trainer. For example, if a personal trainer wants to train the mid section he/she could chose three exercises each EMPHASIZING three separate planes. The personal trainer can chose abdominal crunches as a segital plane exercise, side to side bending with a weighted bar as a frontal plane exercise, and standing cable rotations as a transverse exercise (fig 4). These three exercises can be run one after another in a circuit format and by varying the planes a personal trainer is likely to avoid over-stressing any one movement system with their client.
Notice that I have chosen the word “emphasize”. The truth is that most exercises will place force on more than one plane. The more complex the exercise, the more planes it is likely to affect. For example, the standing cable rotations (fig 4) exert force on the trunk in rotational plane. However, the hips are working in a segital plane. As the torso rotates, one hip moves forward and the other backward, further generating torque need to perform the exercise. So complexity of planes involved in an exercise can be used as another exercise variable. For example a personal trainer can choose to assign his/her client with one plane motion exercise like a segital dumbbell shoulder flexion followed by a standing dumbbell shoulder press with trunk rotation. Single plane exercises will usually isolate muscles and therefore they are more effective at building mass muscles. On the other hand, multi-plane exercises will integrate several muscles groups together so they are more effective at strengthening complex movements. Consequently, pairing the two allows a personal trainer to train the shoulders without over stressing them.
It is also important to notice that when you change planes you do not work different muscles but rather different sequence of muscles. For example, the psoas muscle is involved in all three trunk exercise I previously described. Psoas is a jack of all trades muscle, as it assists in side bending, rotation and forward movement of the torso.
Training Utility of Planes of Motion
So let’s think how we can us this concept to better train abs. I have often talked with people who would want to strengthen their abs because their lower back was in pain. So, they have chosen to do about 100 sit ups every day. There is a good chance that the body is tightening the lower back muscles, thus causing pain, to protect the body from going into that crunch position over and over again. In other words, the body has been overstressed in segital plane. I am not saying that abdominal crunch is a bad exercise. Abdominal crunch is a great exercise. What I am trying to say is that abdominal muscles do more than crunch and to effectively train them a personal trainer should choose exercises that work all movements these muscles are involved in. Here is a list of just a few common exercises in which the abdominal muscles are crucial in:
Squat (with bar) – assisting in maintaining neutral spine position
Side to side lunges – assisting in keeping the torso upright
Standing cable chest fly-the cable is pulling your torso back, abs cat to prevent this
Standing triceps extension (especially when leaning forward-cable is pulling body up abs are pulling the torso down)
Torso cable rotations -assist, along with back extensors, at keeping the torso upright.
All of these exercises will work the abs. HOWEVER the nature of the work the abs are doing will be different in each exercise. In some exercises the abs work as primary movers. In other exercises the abs are assisting at keeping stability, especially when a plane of motion is stressed in which the abs are not moving in (i.e. side to side lunge). Once again, the difference in how abs work in each exercise can be used as a variable that can be utilized as a variation to a training routine.
Why is this information important? Muscle stiffness, and eventually injury, is often caused by continual stress in a specific position or sequence of movement. For example, most people get stiffness in their neck and shoulders by sitting in front of computer for 40 hours a week. Another example is a runner who performs same movement, thousands times a week, exposing his/her body to the same profile of force (segital force loading). So, in order to avoid injuries, and order to keep your body well balanced and stiffness free- learn how to vary planes when working out.