Core Training Fundamentals for Martial Artists.

Core Training Fundamentals for Martial Artists.
By Charles Staley, B.Sc, MSS
Director, Staley Training Systems

In sports training jargon, the abdominal and low back musculature are often referred to as the "core" of the body. The importance of these muscles to athletes is that they transmit forces— either from the lower extremities to the upper extremities (such as when a boxer executes a punch against the heavy bag), or from the upper body to the lower body (such as when a martial artist delivers a spin crescent kick).

The core musculature also plays a significant role in stabilization during almost every movement, from squatting in the weight room, to running, throwing, and jumping.

Additionally, the abdominals play an important role in protecting the body during moments of extreme exertion, such as lifting a very heavy weight, or in absorbing an impact (such as a fall during judo practice). Specifically, during such an exertion, the athlete will instinctively exhale against a closed glottis, called the valsalva maneuver. This exhalation creates greater intraabdominal pressure, which acts to stabilize the lumbar spine from the inside.

In his popular and informative training seminars, abdominal training expert Paul Chek makes the point that when the stabilizer muscles possess inadequate strength, the motor cortex of the brain will not allow the prime movers to contract to their expected potential. This is simply a protective mechanism— if the body realizes that it can't stabilize a certain movement, it simply won't allow the movement to be performed.

My experience working with athletes in a variety of sports collaborates Chek's sentiments. In fact, an easy way to make almost anyone stronger is to improve abdominal strength. Many martial artists intuitively recognize this fact, but our experience reveals that most martial artists (and athletes in general) cling to outdated and ineffective methods for training the core muscles of the body. In the following section, I will present methods (and justifications for these methods) of training the core musculature.


Core Musculature Function

The core area of the body can be be categorized into five groups of muscles, according to function:

1) The trunk flexors (the rectus abdominous) 2) The trunk extensors (the erector spinea) 3) The side flexors (quadratus lumborum) 4) The flexor-rotators (the internal and external obliques) 5) The hip flexors (the illiopsoas, illiacus, and rectus femoris)


Training the Trunk Flexors

The primary trunk flexor is the rectus abdominous. This muscle originates at the diaphragmatic arch, and inserts into the pubic symphysis of the pelvis. Since the primary function of this muscle is to flex the trunk (such that the sternum and pelvis are drawn toward each other), the most direct and effective exercises are those which cause trunk flexion. Any form of crunch or reverse crunch serves this function best. All abdominal muscles are composed of predominately slow-twitch fibers, and as such, tend to respond best to high repetition sets.

The trunk flexors may also be trained through "hanging leg-raises" and related movements, as long as the exerciser maintains a 90 degree angle between the thighs and trunk. Since this is extremely difficult— even for very strong athletes— we generally recommend avoiding this type of movement.
During crunches and similar movements, the athlete can modify arm position in order to manipulate the level of resistance. The least resistance occurs when the arms are straight and outstretched along the side of the body during the movement.

A more difficult variation is to cross the arms against the chest during the exercise. The most difficult variation is to place the hands such that the fingers are touching the head at a point just behind the ears. Avoid interlacing the fingers and clasping behind the head, which can strain the cervical vertebrae, and encourage co-contraction from other muscles. Additional resistance (in the form of a medicine ball or weight plate) can be used when the athlete's bodyweight is no longer sufficient to cause an improvement in strength. Note: Avoid anchoring the feet and extending the legs, since these practices tend to shift the exercise stress away from the trunk flexors and onto the hip flexors.

Training the Trunk Extensors: The erector spinae are the predominant trunk extensors. Strong trunk extensors are necessary to balance the strength of the rectus abdominous, and to maintain efficient postural stabilization and control. They are most commonly trained through the use of the back extension exercise, performed on a specialized apparatus designed for this purpose. However, in order to minimize co-contraction from the gluteals and hamstrings, the athlete should be positioned in such a way that the navel is directly over (not in front of) the pad or bench. With this positioning, the pelvis is stabilized, allowing the exercise stress to fall directly onto the erectors.


Training the Side Flexors and the Flexor-rotators

One of the most common "ab" exercises seen in commercial gyms and health clubs today is the dumbbell side bend. Most proponents of this movement recommend it as an exercise for the obliques, but in reality, it is an exercise for the quadratus lumborum— the primary side flexor. For martial artists who rely heavily on kicking skills, the side flexors should be systematically trained. But most other athletes (who don't have a reason) should avoid training this muscle, since over-developed side flexors have been associated with low back pain. Further, performing side bends has no significant effect on the waistline, since the quadratus lumborum is such a deep-lying muscle.


Training the Flexor-rotators

The flexor-rotators are the internal and external obliques. These muscles cause trunk flexion as well as rotation when they contract unilaterally (one side at a time), but cancel each other out, causing only trunk flexion when they contract bilaterally (both sides simultaneously). Thus, uni-lateral exercises, such as twisting crunches, are most effective for developing these muscles.

When performing twisting crunches and their variations, use the same guidelines that were presented in the section on trunk flexion, with the exception that the exercises should curl the trunk up and diagonally, such that the left armpit approaches the right hip, and vice versa. Avoid touching elbow to opposite knee, as this encourages too much cervical and hip flexion.

Training of the flexor-rotators should be prioritized over the pure flexors, since most athletic and day-to-day activities involve rotation with flexion, as opposed to pure flexion.


Training the Hip Flexors

Many people excessively train the hip flexors thinking that they're training the abdominals. Sit-ups, leg raises, "flutter kicks," and hanging leg raises are all primarily hip flexor exercises. That doesn't necessarily make them bad, but most people tend to have chronically short hip flexors, which can compromise the structural dynamics of the lumbar spine. Short hip flexors are also associated with low back pain. Of course, martial artists must have strength in these muscles, but normally, time spent drilling with kicks is sufficient for this purpose.

Many martial arts techniques involve simultaneous hip flexion, trunk flexion, and rotation. For this reason, I recommend using a wide variety of exercises. An excellent tool is the "physio-ball"— an oversized "beach ball" which can be used for a variety of core exercises, including crunches, sit-ups, back extensions, and many more. With a little experimentation, you can devise dozens of multi-planar exercises which have a high degree of transfer to your sport techniques. Medicine balls are also an invaluable tool for core training.

Many exercises can be developed using the medicine ball and physio-ball together. An example is to sit on the physio-ball (feet anchored by heavy dumbbells), and perform medicine ball sit-ups with a partner. The unstable environment provided by the physio-ball, combined with the ballistic, multi-planar aspects of the medicine ball throws, makes this a fruitful exercise for those desiring sport-specific strength.

Core training can be periodized over the training cycle. Early in the cycle, exercises tend to be single plane, of a slow, steady tempo, and conducted in a stable environment. Another goal during the early stages of the training cycle is to eliminate weaknesses, so special attention is paid to muscles which need extra conditioning. Gradually, the emphasis shifts to multi-planar, ballistic exercise conducted in a less stable environment.

Abdominal training and bodyfat deposition

Abdominal training does not significantly affect the layer of fat which oftentimes covers these muscles. Many people become a slave to crunches, situps, and TV info-mercial devices, when the real issue is bodyfat, not abdominal conditioning. In fact, many of these people probably have superbly conditioned abs. Bodyfat is reduced through a comprehensive training program incorporating resistance training and caloric manipulation— NOT abdominal training!