To help answer the question of whether hyper extension exercises on a roman chair are appropriate as part of your spine rehabilitation program, first let me provide some background information on the subject. Then, I will describe the muscle control problems that arise with back pain. Next, we need to establish goals for rehabilitation and determine the specific training requirements to obtain those goals. And finally, I will describe the inherent problems of traditional roman chairs, followed by a solution.

Muscle Control during Optimal Health
Research has shown that there are two types of muscles: Superficial strength muscles, and deep stabilizing muscles. Each has its own unique characteristics.

Think of the superficial strength muscles as “sprinter-type” muscles. These muscles contain the same type of muscle fibers that are highly developed in the legs of Olympic sprinters. They are great for producing speed during a 100 meter dash but poor for endurance during a marathon. In contrast, the deep stabilizing muscles are more like “marathon-type” muscles (superior for endurance but poor for speed).

In healthy individuals, the primary role of the superficial strength muscles of the lower back and abdomen is to move the torso. (Torso is defined as: The human body excluding the head, neck, and limbs. This part of the body is also known as the trunk. So, these muscles move the rib cage, lumbar spine, and pelvis.) They are also responsible for controlling trunk posture during high-level activities. These activities may include: lifting, pushing, pulling, jumping, running, and other ballistic (fast) movements of the limbs.

In contrast, the deep stabilizing muscles of the back and abdomen are used to provide continuous postural adjustments of the torso throughout the day during low-level activities. Some examples of low-level activities are: sitting, standing, moving from a seated to standing position, walking, and slow (non-ballistic) movements of the limbs.

Muscle Control Problems that Arise with Back Pain
After experiencing back pain, the brain’s strategy for maintaining trunk posture changes to a simplified, inferior strategy. First, the deep stabilizing muscles stop working properly. Second, the superficial strength muscles of the trunk become over-active and their muscle fibers shorten up to restrict trunk range of motion.

This over-active/shortening-up response is recognized by experts as the brain’s attempt to "lock up" and protect the painful segments of the torso during the acute phase of injury. This compensation pattern typically continues after it is no longer necessary during the chronic phase of back pain (when the injured soft tissue structures have healed).

The strategy of using “sprinter-type” muscles to try to maintain trunk posture throughout the day is like forcing an Olympic sprinter to compete in a marathon, instead of the 100 meter dash. Obviously, the sprinter’s muscles are built for speed, not endurance. So to say the least, this strategy would not be very efficient. But, other problems arise secondary to muscle fatigue and subsequent muscle spasm which result in disc & joint compression.

Goals for Rehabilitation & Specific Training Requirements
Just as the goals and specific training requirements for sprinters are different than for marathon runners, there are also vast differences in the goals and specific training requirements for a rehabilitation program versus a core fitness routine.

In rehabilitation, one of our goals would be to release the superficial strength muscles. (Remember that they have “locked up” the injured region of the spine.) This is accomplished through slow, low-load, pain-free movement patterns focused on lengthening the superficial strength muscles while relaxed. This is something I describe to my patients as a relaxed muscle release exercise (not to be mistaken as a muscle-stretch exercise).

Although it is true that we must stretch the fascia and related non-contractile tissues, it is important to recognize that muscles must be released while relaxed. This is required in order to reset the muscle spindles that control the set-point of resting tone and muscle length.

The idea of a relaxed muscle release exercise is definitely a change in mind-set. What it means is that typical hyper extension exercises performed on a roman chair bench are not appropriate for the initial stages of rehabilitation for chronic back pain.

If the superficial strength muscles of the back and abdominal wall are over-active (contracting too much) and the muscle fibers are shortened up to restrict trunk range of motion, then “strengthening” exercises would not be the proper type of exercise for rehabilitation.

Our next goal would be to retrain the deep stabilizing muscles in their role as the primary trunk stabilizers during low-level activities. This is difficult to achieve in a person with chronic back pain since the superficial strength muscles are attempting to perform that role by over-contracting and shortening up to restrict motion in the previously injured region of the torso. Therefore, an aggressive exercise utilizing a roman chair that emphasizes the superficial strength muscles of the torso and hips may neglect to activate the deep stabilizing muscles appropriately. A more specific training approach is required.

One important deep stabilizing muscle of the back is called lumbar multifidus. This muscle attaches at each segment of the lumbar spine down to the sacrum and pelvis. The specific training that I recommend on a back exercise machine is a slow, low-load extension movement occurring at each vertebra, instead of holding the curve of the lower back in a locked position while moving through the hips. This exercise should be easy enough to perform 30 repetitions without fatigue.

The Problem and the Solution
The specific training requirements for lumbar multifidus rehabilitation are not likely to be achieved as part of a home exercise program on a traditional roman chair hyper extension bench. The design of the traditional 90-degree exercise angle is too difficult and not properly designed to promote the specific training requirements of spine rehabilitation. This type of roman chair will emphasize the hamstrings, buttocks and superficial strength muscles of the lower back. It is also likely that training on the 45-degree exercise angle will be too difficult and not specific enough.

Fortunately, a solution has been developed that may be designated as a hybrid of the roman chair hyper extension bench. It’s called the Back Trainer Medic by Kettler (made in Germany). The Back Trainer Medic was designed to assure the correct movement pattern, so the individual segments of lumbar multifidus are trained appropriately. The torso pad is curved and the height of the pad is adjustable so it guides the user through the correct motion of the torso for spinal rehabilitation.

The specific exercises that I show my patients to perform on the Back Trainer Medic fulfill both goals that I addressed earlier in this article: First, releasing the superficial strength muscles of the back (via relaxed muscle release exercises), and second, retraining the deep stabilizing muscle of the back, called lumbar multifidus (via a slow, low-load extension movement occurring at each vertebra). The specific exercises are also demonstrated on a DVD video so my patients can watch it at home as an additional guide.