In
kinesiology
Kinesiology () is the scientific study of human body movement. Kinesiology addresses physiological, anatomical, biomechanical, pathological, neuropsychological principles and mechanisms of movement. Applications of kinesiology to human health ...
, core stability refers to a person's ability to stabilize their
core (all parts of the
body
Body may refer to:
In science
* Physical body, an object in physics that represents a large amount, has mass or takes up space
* Body (biology), the physical material of an organism
* Body plan, the physical features shared by a group of anima ...
which are not
limb
Limb may refer to:
Science and technology
* Limb (anatomy), an appendage of a human or animal
*Limb, a large or main branch of a tree
*Limb, in astronomy, the curved edge of the apparent disk of a celestial body, e.g. lunar limb
*Limb, in botany, ...
s). Stability, in this context, should be considered as an ability to
control the position and movement of the core. Thus, if a person has greater core stability, they have a greater level of control over the position and movement of this area of their body. The body's core is frequently involved in aiding other movements of the body, such as
running
Running is a method of terrestrial locomotion allowing humans and other animals to move rapidly on foot. Running is a type of gait characterized by an aerial phase in which all feet are above the ground (though there are exceptions). This is ...
; thus it is known that improving core stability also improves a person's ability to perform these other movements.
The body's core region is sometimes referred to as the
torso
The torso or trunk is an anatomical term for the central part, or the core, of the body of many animals (including humans), from which the head, neck
The neck is the part of the body on many vertebrates that connects the head with the tors ...
or the trunk, although there are some differences in the muscles identified as constituting them. The major muscles involved in core stability include the
pelvic floor
The pelvic floor or pelvic diaphragm is composed of muscle fibers of the levator ani, the coccygeus muscle, and associated connective tissue which span the area underneath the pelvis. The pelvic diaphragm is a muscular partition formed by the l ...
muscles,
transversus abdominis
The transverse abdominal muscle (TVA), also known as the transverse abdominis, transversalis muscle and transversus abdominis muscle, is a muscle layer of the anterior and lateral (front and side) abdominal wall which is deep to (layered below) th ...
,
multifidus
The multifidus (multifidus spinae : ''pl. multifidi'' ) muscle consists of a number of fleshy and tendinous fasciculi, which fill up the groove on either side of the spinous processes of the vertebrae, from the sacrum to the axis. While very th ...
,
internal
Internal may refer to:
* Internality as a concept in behavioural economics
*Neijia, internal styles of Chinese martial arts
*Neigong
Neigong, also spelled ''nei kung'', ''neigung'', or ''nae gong'', refers to any of a set of Chinese breathing, ...
and
external obliques,
rectus abdominis
The rectus abdominis muscle, ( la, straight abdominal) also known as the "abdominal muscle" or simply the "abs", is a paired straight muscle. It is a paired muscle, separated by a midline band of connective tissue called the linea alba. It exte ...
,
erector spinae
The erector spinae ( ) or spinal erectors is a set of muscles that straighten and rotate the back. The spinal erectors work together with the glutes (gluteus maximus, gluteus medius and gluteus minimus) to maintain stable posture standing or sitti ...
(sacrospinalis) especially the
longissimus thoracis
The longissimus ( la, the longest one) is the muscle lateral to the semispinalis muscles. It is the longest subdivision of the erector spinae muscles that extends forward into the transverse processes of the posterior cervical vertebrae.
Structur ...
, and the
diaphragm. Notably,
breathing
Breathing (or ventilation) is the process of moving air into and from the lungs to facilitate gas exchange with the internal environment, mostly to flush out carbon dioxide and bring in oxygen.
All aerobic creatures need oxygen for cell ...
, including the action of the diaphragm, can significantly influence the
posture and movement of the core; this is especially apparent in regard to extreme ranges of inhalation and exhalation. On this basis, how a person is breathing may influence their ability to control their core.
Some researchers have argued that the generation of intra-abdominal pressure, caused by the activation of the core muscles and especially the transversus abdominis, may serve to lend support to the
lumbar spine
The lumbar vertebrae are, in human anatomy, the five vertebrae between the rib cage and the pelvis. They are the largest segments of the vertebral column and are characterized by the absence of the foramen transversarium within the transverse p ...
. One way in which intra-abdominal pressure can be increased is by the adoption of a deeper breathing pattern. In this case, and as considered by Hans Lindgren, 'The diaphragm
..performs its breathing function at a lower position to facilitate a higher IAP.' Thus, the adoption of a deeper breathing pattern may improve core stability.
Typically, the core is associated with the body's
center of gravity
In physics, the center of mass of a distribution of mass in space (sometimes referred to as the balance point) is the unique point where the weighted relative position of the distributed mass sums to zero. This is the point to which a force may ...
(COG). In the '
standard anatomical position
The standard anatomical position, or standard anatomical model, is the scientifically agreed upon reference position for anatomical location terms. Standard anatomical positions are used to standardise the position of appendages of animals with ...
' the COG is identified as being anterior to the second
sacral vertebrae
The sacrum (plural: ''sacra'' or ''sacrums''), in human anatomy, is a large, triangular bone at the base of the spine that forms by the fusing of the sacral vertebrae (S1S5) between ages 18 and 30.
The sacrum situates at the upper, back part ...
. However, the precise location of a person's COG changes with every movement they make. Michael Yessis argues that it is the lumbar spine that is primarily responsible for posture and stability, and thus provides the strength and stability required for dynamic sports.
In practice
Whenever a person moves, to lift something or simply to move from one position to another, the core region is tensed first. This
tension is usually made unconsciously and in conjunction with a change in breathing pattern. An example to try is to sit in a chair and to reach forward over a table to pick up a cup. This movement is first accompanied by a tension in the core region of the abdomen and can be felt by placing one hand on the abdomen as the movement is made.
As the load increases the key muscles contract around the viscera, which are in-compressible, to form a stable ball-like core region against which the forces are balanced in coordination with posture.
It is commonly believed that core stability is essential for the maintenance of an upright
posture and especially for movements and lifts that require extra effort such as lifting a heavy weight from the ground to a table. Without core stability the lower back is not supported from inside and can be injured by strain caused by the exercise. It is also believed that insufficient core stability can result in lower back pain and lower limb injuries..
Research
There is little support in research for the core stability model and many of the benefits attributed to this method of exercise have not been demonstrated. At best core stability training has the same benefits as general, non-specific exercise (see review by Lederman 09) and walking. Trunk or core specific exercise have failed to demonstrate preventative benefits against injuries in sports or to improve sports performance.
Training methods
Training methods for developing and maintaining core stability include:
*
Pilates
Pilates (; ) is a type of mind–body intervention, mind-body exercise developed in the early 20th century by German physical trainer Joseph Pilates, after whom it was named. Pilates called his method "Contrology". It is practiced worldwide, es ...
*
Exercise ball
An exercise ball is a ball constructed of soft elastic, typically in 5 diameters of 10-centimeter increments, from 35 centimeters (14 inches) to 85 centimeters (34 inches), and filled with air. The air pressure is changed by removing a valve s ...
, also known as a Swiss ball, stability ball,
yoga
Yoga (; sa, योग, lit=yoke' or 'union ) is a group of physical, mental, and spiritual practices or disciplines which originated in ancient India and aim to control (yoke) and still the mind, recognizing a detached witness-conscio ...
ball,
Pilates
Pilates (; ) is a type of mind–body intervention, mind-body exercise developed in the early 20th century by German physical trainer Joseph Pilates, after whom it was named. Pilates called his method "Contrology". It is practiced worldwide, es ...
ball or fitness ball
*
Yoga
Yoga (; sa, योग, lit=yoke' or 'union ) is a group of physical, mental, and spiritual practices or disciplines which originated in ancient India and aim to control (yoke) and still the mind, recognizing a detached witness-conscio ...
Exercise for strengthening of the cervical, thoracic and lumbar spine
The
cervical
In anatomy, cervical is an adjective that has two meanings:
# of or pertaining to any neck.
# of or pertaining to the female cervix: i.e., the ''neck'' of the uterus.
*Commonly used medical phrases involving the neck are
**cervical collar
**cervic ...
,
thoracic
The thorax or chest is a part of the anatomy of humans, mammals, and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main divisions of the crea ...
and
lumbar
In tetrapod anatomy, lumbar is an adjective that means ''of or pertaining to the abdominal segment of the torso, between the diaphragm and the sacrum.''
The lumbar region is sometimes referred to as the lower spine, or as an area of the back i ...
spine is composed of a total of 24
presacral vertebrae
The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...
and their main functions are to protect the spinal cord, provide an attachment site for many muscles of the body. They also function by distributing one's bodyweight when standing upright. Many injuries to the spine occur as a result of
vehicle accidents,
falling, and
sports
Sport pertains to any form of competitive physical activity or game that aims to use, maintain, or improve physical ability and skills while providing enjoyment to participants and, in some cases, entertainment to spectators. Sports can, ...
and
recreation
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or ple ...
. While it is impossible to prevent such events from happening, increasing intra-abdominal pressure and strengthening the musculature in the back, along with keeping a neutral spine, can minimize injuries like
hernia
A hernia is the abnormal exit of tissue or an organ, such as the bowel, through the wall of the cavity in which it normally resides. Various types of hernias can occur, most commonly involving the abdomen, and specifically the groin. Groin hern ...
s,
strains, and
sprains
A sprain, also known as a torn ligament, is an acute soft tissue injury of the ligaments within a joint, often caused by a sudden movement abruptly forcing the joint to exceed its functional range of motion. Ligaments are tough, inelastic fibers ...
.
Intra-abdominal pressure
The correlation between having a significant amount of core strength and spinal health has been well documented by many studies in the past. Some of these studies were able to quantify the effects that antagonizing abdominal muscle had on stabilizing the lumbar spine by increasing the amount of intra-abdominal pressure in order to maintain a straight lumbar spine and to avoid rounding during physical activities and using simple techniques such as the “
Valsalva maneuver
The Valsalva maneuver is performed by a forceful attempt of exhalation against a closed airway, usually done by closing one's mouth and pinching one's nose shut while expelling air out as if blowing up a balloon. Variations of the maneuver can ...
”.
[Goldish, MD, G., Quast, MD, J., Blow, MD, J., & Kuskowski, PhD, M. (1994). Postural Effects on Intra-Abdominal Pressure During Valsalva Maneuver. Arch Phys Mad Rehabil ,, Vol75, 324-327.] A simple exercise used to strengthen the abdominals (rectus abdominis, internal/external obliques, and transverse abdominis) is using the isometric or “static” hold known as
the plank.
Strengthening back musculature
Simply by working to keep a neutral spine and remembering to increase intra-abdominal pressure before performing a movement that could compromise the spine, you are able to drastically decrease your risk for sustaining a back injury. If you were looking for ways to both strengthen and increase stability of the musculature of the spine one could perform various body weight exercises, for instance the
bird dog exercise.
See also
*
Human abdomen
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso ...
*
Sit ups
The sit-up (or curl-up) is an abdominal endurance training exercise to strengthen, tighten and tone the abdominal muscles. It is similar to a crunch (crunches target the rectus abdominis and also work the external and internal obliques), but ...
*
Running
Running is a method of terrestrial locomotion allowing humans and other animals to move rapidly on foot. Running is a type of gait characterized by an aerial phase in which all feet are above the ground (though there are exceptions). This is ...
References
Inline citations
General references
*
* {{cite book , author=Mel Cash , title=Pocket Atlas of the Moving Body: For All Students of Human Biology, Medicine, Sports and Physical Therapy , year=1999 , publisher=Trafalgar Square Publishing , location=North Pomfret, Vt , isbn=0-09-186512-3
Physical exercise
Pilates