Skinny on Abdominal Strengthening
(Marilee Nugent), BSc, Kinesiology, BA Art & Culture
Fitness gurus promote
the current research-based wisdom that a balanced fitness program
should include regular cardiovascular (aerobic) exercise, muscle
strength and endurance training and flexibility training. Increasingly,
experts recommend including a core strengthening component
in our exercise programs.
probably heard the terms neutral spine and core
balance being bandied about, and seen numerous class
offerings for Pilates, body ball, and core workouts. You
may be wondering, is this the sort of thing you should be
If any of your health
and fitness goals include reducing back pain and strain, recovering
from or avoiding low back injury, enhancing physical performance
in sport and leisure activities, improving posture and feeling
stronger and more centered, the answer is unequivocally, YES!
Having good abdominal
muscle fitness goes far beyond improving our looks and broadening
our fashion options, although these are some of the fun side
effects. Lack of core strength and stability, largely due to
our sedentary lifestyles, is believed to be a major risk factor
for lower back pain and injury. The incidence of low back pain
in adults of all ages is pervasive and the cost to employers,
health care and compensation systems is not insignificant.
Canada, low back pain is the cause of 21 million disability
days annually and 80% of individuals suffer from low back
pain at some point in their lifetimes. Incidences range in
severity from temporary annoyance to complete debilitation.
In the U.S. the annual cost of back pain related care and
disability compensation is $50 billion.
The term “core” refers
to the muscles of the trunk that support the back and connect
the ribcage to the pelvis and the pelvis to the legs. Good
core strength and stability provides the capability to maintain
a “neutral spine”— an ideal alignment between pelvis and upper
trunk that distribute pressure evenly amongst the vertebrae
and support structures and produces the least amount of mechanical
stress on joints. In the neutral spine position, the lumbar
vertebrae are stacked up nicely so that there is no excess
curvature forward, backward or sideways, which can cause uneven
pinching of the intervertebral discs and which can lead to
disc bulging, wear and tear or even rupture. More often, a
habitual non-neutral lumbar spinal curvature simply results
in unnecessary back discomfort, muscle fatigue, and strain.
Ergonomic design of work chairs and stations are designed to
support and allow better spine position through external support,
but they are no substitute for actual core strength. Unfit
core muscles render us susceptible to injury from performing
even the simplest tasks such as bending over to pick up a pencil.
A huge amount of research
has been and continues to be done on what kinds of stress the
back can withstand and how much it takes to cause pain and
injury. How strong is the human spine? This depends
on whether what is being tested is the functional strength
of an intact, living human, or just the bony vertebral column
extracted from a cadaver.
individual vertebrae can withstand loads of 900 to 2800 lbs
of pressure before breaking, the extracted human spine with
muscles removed will buckle under a compressive load of just
How can something
so apparently flimsy withstand the kinds of forces a power
lifter subjects his back to in routinely lifting loads of over
Rectus Abdominus (top layer)
Transverse Abdominus (deepest layer)
External & Internal Obliques
1 Schematic drawing of Muscles of abdominal wall
2 Schematic drawing of spine muscles
This discrepancy between
what the extracted and in vivo (living) skeletal spine can
withstand underlines the importance of the role of muscles
and ligaments to back stability and support strength. Muscles
provide active stiffness through the control of the nervous
system—greater activation equates to greater stiffness. Ligaments
provide passive stiffness through their resistance to stretch.
Increasing the stiffness of joints provides greater stability
and functional strength. Injuries tend to weaken ligaments
as well as produce abnormal coordination patterns amongst the
muscles of the joint. Sedentary lifestyle may also result in
reduced muscle coordination and strength due to disuse. Decreased
strength/endurance and coordination both result in increased
instability of the joint and an increased likelihood of injury
or re-injury. Both prevention and injury rehabilitation strategies
focus on retraining the muscle patterns that provide active
support while enhancing muscular strength and endurance so
support can be maintained.
Balanced muscle activation is the key to lower back health and
Dr. Stuart McGill of the University of
Waterloo in Ontario is a leading researcher in lower back conditioning,
injury and rehabilitation. To illustrate the importance of the
musculature in spinal stability, he uses the analogy of the spine
as an upright fishing rod standing on its butt. Press on the
top end and it will easily buckle, but attach guy wires at different
levels and in different directions, and tension each wire to
the same tension and you create a stable structure even under
very large compressive loads (weight).
Interestingly, the guy
wires don’t need to have high-tension forces to make the structure
very stable—what’s important is that they must be balanced.
It is the job of the motor control system to regulate the balanced
activation of muscle tension that creates spinal stability
McGill believe that many back injuries
result from a motor control error in which one muscle loses
its stiffness and upsets the balance, allowing the spine to
buckle, resulting in vertebral disc and endplate fractures,
ligament and muscle damage, or disc rupture. Because the muscles
that provide spinal stability must work together in harmony,
it is not enough just to strengthen individual muscles. More
importantly, they must be trained to work together to automatically
maintain spinal support and stability during a wide range of
activities. Also, the absolute strength of these muscles is
less important than endurance, since they must be able to maintain
activity throughout our daily and recreational activities.
Which muscles do we need to train?
at left, lists muscle identified as being important to core stabilization
addition to having their own roles in producing specific movements.
Stability occurs when they are co-contracted, or activated
together. Note that this list is not limited to the “6-pack”
(rectus abdominus) which if developed on its own to the exclusion
of the other abdominal muscles, will not teach stable low back
support and can even cause a more rounded upper back posture
by shortening and pulling the ribs closer to the pelvis.
1 and 2 show schematic drawings of the muscles of the abdominal
wall and back respectively, which when activated together
provide support and stability for the lower back. From this
diagram you can easily see these muscles are “engineered”
as a group to provide stability to the lumbar spine
when they are activated
together, creating even and balanced pull in connecting upper
and lower trunk. Again, they don’t have to work at 100% to
greatly increase stability—10% of their maximum is considered
The relative contribution
of each muscle to stability depends on the dynamically changing
nature of movement demands such as body position, amount of
weight lifted, balance and range of motion required. As McGill
says, “sufficient stability is a moving target”. During physical
activity there is a conflict between breathing and stability;
however, fit muscles are able to meet the dual demands whereas
unfit muscles and poorly coordinated muscle groups are not.
Pilates addresses this issue by training challenging breathing
patterns while maintaining support. Core strength training
begins with learning to isolate the individual muscles while
lying down, progressing to maintaining coordinated activation
of all (i.e. neutral spine) during a variety of positions and
functional activities, such as bending over, picking things
up, performing weight training or sports movements. The effectiveness
(and safety!) of both of these training methods will depend
largely on the competence of the instructor. Find out their
credentials—a weekend certification course is insufficient
training. They should have basic knowledge in fitness, biomechanics
and be certified by a recognized organization.
Which exercises are best?
have investigated the possible benefits of commercially available
abdominal exercise aids such as the Ab Roller, Abslide, ABSculptor,
AB Trainer and AbWorks and compared them to traditional abdominal
exercises that don’t require equipment.
No significant difference was found between these aids
and the traditional trunk curls in terms of level of activation
of abdominal muscles.
that the best combination of exercises to ensure sufficient
strengthening of the abdominal muscles are the traditional
half trunk curl and cross curl up in bent knee position for
the rectus, plus side bridges for the obliques. Back extension
exercises to strengthen the muscles along the spine, can be
done lying on a ball the feet braced against a wall. Core strengthening
exercises teach all these muscles to co-contract in a coordinated
way to maintain trunk stability during movement.
agree that exercises which strongly activate the psoas muscles
(hip flexors) should be avoided by all but very fit individuals
who require more challenging sport-specific training, since
these muscles cause large compressive loads on the lumbar spine
but don’t contribute to back stability.
the general population and especially those recovering from
low back injury should avoid straight leg raises and full
sit ups, since these exercises emphasize psoas activity but don’t strongly
activate the abdominal muscles specifically involved in core
strength and stability.
To find out the state
of your core strength and balance, and your possible injury
risk due to being imbalanced and/or weak, get tested by a certified
fitness consultant in your area (many fitness centres and gyms
employ then). Once you’ve learned core strength exercises you
can easily practice them at home several times a week to develop
and maintain core strength and stability. Benefits include
improved posture and appearance (you’ll be able to stand taller
and reshape your waist without even losing weight!) improved
performance in sports, dance and daily activities, improved
energy level (gravity can’t weigh you down as much when you
are standing straighter), decreased back muscle and joint pain,
and decreased risk of injury.
343 Active Health: Assessment & Programming course notes,
- Kin 380 Occupational Biomechanics, course notes, SFU.
- Intro. to Core Stability – BCAK course with Rick Kaselj.
- Juker, D., MCGill,
S., Kropf, P., Steffen, T. 1998. Quantitative intramuscular
myoelectric activity of lumbar portions of psoas
and the abdominal wll during a wide variety of tasks. Medicine & Science
in Sports & Exercise.
- Hildenbrand, K., Noble, L. 2004. Abdominal muscle activity while
peforming trunk-flexion exercises using the Ab Roller, ABslide,
FitBall, and conventionally performed trunk curls. Journal
of Athletic Training 39, pp. 37-43.
- McGill, S. Chapter
6: Lumbar Spine Stability. Low Back Disorders.
US: Human Kinetics, 2002.
a comment? Send us a
Check the "Letters to the Editor" for
other possible viewpoints!
the Scenes of " Bellydance Workout" by Venus
television crew said that in the control room it was dead silent
during filming as they strained to listen to what I was saying
so they’d know where to aim the shots.
Breathing for Better Dance Performance by Taaj
also hold our breath when we concentrate or get nervous. This brings
tension into our bodies. The more tension we have, the more shallow
we breathe. It can become a vicious circle!
ATS Charm in Taipei: Devi Mamak by Lisa Chen
both of us are not based in San Francisco, we share many common
factors in terms of learning ATS and developing our own visions
for it back in our own home venues.
Dancer, A Journey of Self- Acceptance by Melodi
it wasn’t long before I started to realize that the other
girls were different than me. More importantly, I realized that
I was different from them.
Peek at Making Music Videos: Hakim, Khalid Selim, Walid
Toufic, Ali el Hagar, Elam, & Samira Said by
was either crying or yelling at Hakim for most of the shoot and
went home each day with a headache from it.
- Deeper than the Moves by Keti Sharif
dancer who feels “safe”in the rhythm, footwork, technical
movement feels grounded and secure as she dances. A grounded
dancer will be less "in her head”and allow the authenticity
of feeling to come through her body as a flowing, emotive movement
that expresses the music and how she “feels”the music.
feel the music when you're on stage!”Interview
with Ozgen, Male Turkish Belly Dancer, by Nini
I think my heart still beats for big shows and productions, as
much as I know how stressful and difficult that show-life can
be. I seem to not be able to live without it.
and the Bellydancer by Taaj
then, I wondered, why are so many belly dancers jealous, unhappy,
competitive and insecure? Does belly dance really build self-esteem?