Dr. Timothy Haines decided to make a New Year's resolution
to improve his musculoskeletal health. When he began
working with a personal trainer at his gym, the last thing he
expected was that certain exercises and gym machines would
worsen his musculoskeletal pain. Frustrated after two months of
increasing pain, he quit his training sessions and sought treatment
from a physical therapist.
This is just one of numerous negative exercise stories I hear
from dentists. Unfortunately, most personal trainers and therapists
do not realize that dentists are predisposed to unique muscle
imbalances. Certain generic exercises that are not a problem
for the general population can throw the dentist into a vicious
pain cycle. When dentists come to understand these muscle
imbalances, the proverbial light bulb appears… “Ah, that's why
I always had pain after that exercise.”
When dentists become familiar with their muscle imbalances,
they are better able to select exercises and modify existing
exercise routines to improve their health - not make it worse. In
addition to selecting proper exercises, it is imperative to understand
how dentists should strengthen these muscles. Research
shows that a method called muscular endurance training can
help dental professionals reduce work-related pain.1-4
Developing balanced musculoskeletal health through proper
exercise can help dentists avoid work-related pain, injury or
early retirement. Before initiating exercise, dentists should
resolve operatory ergonomic issues, have full range of motion,
resolve their trigger points and be relatively pain-free.5
Pain and Unbalanced Muscles
In order to perform the precision tasks of dentistry, the arms
must have a stable base from which to operate. For example, the
delivery of dental care requires excellent endurance of the shoulder
girdle stabilizing muscles (especially the middle and lower
trapezius muscles) for safe shoulder movement and working posture.
These shoulder stabilizing muscles tend to fatigue quickly
with forward head, rounded upper back and elevated arm postures
- all commonly seen among dentists.6 When these muscles
fatigue, other muscles (upper trapezius, levator scapula and upper
rhomboids) must compensate and become overworked, tight and
This muscle imbalance may result in tension neck syndrome, a
frequently diagnosed disorder among dentists. Symptoms include pain, tenderness and stiffness in the neck and shoulder musculature,
commonly with pain that radiates between the shoulder blades or
up into the occiput. Two contributing factors to tension neck syndrome
in dentistry are forward head and elevated arm postures.
Another common imbalance among dentists is in the shoulder,
caused by over-strengthening the deltoid and supraspinatus
muscles. These muscles already tend to be strong in dentists
due to frequent postures with the arms lifted away from the
sides of the body. This imbalance can cause improper movement
at the shoulder joint, with painful impingement of the
rotator cuff tendon.
The muscle imbalance that tends to develop between the
abdominal and low back muscles is especially problematic in seated
dentistry. Leaning toward a patient repeatedly with rounded back
posture can cause strain and overexertion in the superficial low back
extensors, while the deep stabilizing abdominal muscles (transverse
and oblique abdominals) tend to become weaker.
How to Develop an Effective Exercise Program
An effective exercise regimen for dentists will target specific
shoulder girdle, trunk and back stabilizing muscles, without
engaging the muscles that are prone to tightness and ischemia.
This requires expert knowledge of biomechanics and kinesiology.
In addition, specific muscles that are prone to tightness and
ischemia must be targeted with stretching exercise and avoid
strengthening. Male dentists are especially prone to injuries due
to inflexibility and should be diligent with a daily chairside
stretching regimen and/or yoga routine.
Studies show that power/strength training is not protective
against pain syndromes caused by prolonged, static postures, as
in dentistry.1 However, several dental studies show that specific
muscular endurance training can reduce or prevent neck, shoulder
and back pain.
Since the postural stabilizing muscles perform low-level
static contractions for prolonged periods in the dental operatory,
they must be trained for endurance.
- Target the correct muscles with muscular endurance
training: Use light resistance and high repetitions (15-20
reps) when training these muscles, usually an elastic exercise
band is sufficient for the shoulder muscles, while
gravity-resisted exercise on the floor or an exercise ball is
good for the trunk muscles.
- Perform strengthening exercises three times a week,
always allowing one day in-between sessions.
- Target specific tight, ischemic muscles with regular chairside
stretching. Stretching should be performed daily.
- Strengthening exercises should only be performed when
there is no musculoskeletal pain and full range of motion
- Always discontinue exercise if you experience pain.
- It is a good idea to seek professional guidance from a
physical or occupational therapist when beginning any new
exercise regimen and to ensure safety and good technique.
Downward Squeeze (Fig. 1)
This targets one of the primary shoulder girdle stabilizing
muscles. Position door anchor above head level. Loosely wrap
band around both hands and position arms at sides, fingers
pointing upward. Make sure the downward angle of the band is
about 45 degrees. Maintain optimal head posture (ear-overshoulder,
chin tucked) and pull navel to spine, holding this
contraction throughout the exercise to avoid arching your low
back. Roll shoulders back and down, squeezing shoulder blades
downward and together. Pause briefly and slowly return. Repeat
10-20 times. If you have discomfort, decrease the resistance of
the exercise band.
External Rotation (Fig. 2)
This exercise helps correct a painful muscle imbalance in
the rotator cuff that frequently occurs among dentists due to
elevated arm postures. With the door anchor at elbow height,
stand at a right angle to the door holding a small pillow or rolled
towel between your elbow and your body. Squeeze shoulder
blades together then slowly rotate the arm outward, then return.
Keep the elbow pressed firmly against your side throughout the
exercise. You should be able to perform 10-20 repetitions easily.
Repeat with other arm.
Side Lift (Fig. 3)
Research supports endurance training of the quadratus lumborum
in preventing low back pain.3 Lie on your side with arms
crossed. Pull navel to spine and hold as you slowly lift both legs
off the floor, making sure your pelvis does not roll forward or
backward. Briefly hold and repeat 10 times on each side. Repeat
for the other side (page 72).
Lower Abdominals (Fig. 4)
Studies show that individuals who effectively utilize and
train their natural “back belt” - the transverse abdominal muscles
- have less low back pain.7 Lie on your back with knees bent
and feet on the floor. Place your hands under your low back and
pull navel toward your spine. You should now feel your back
pressing into your hands. Be sure that you maintain this contraction
throughout the exercise and do not arch your back,
which may cause strain or injury. Lift one leg until the hip is at
90 degrees. Continue breathing while slowly straightening the
leg. Lightly touch the floor, hold, then return the leg to 90-
degree position. Repeat with the same leg 5-10 times. Now
repeat the exercise with the opposite leg.
Advanced version: Pull navel to spine and bring both legs to 90
degrees. Slowly straighten the right leg, without letting it touch
the floor. Return it to the 90-degree position, then straighten the
left leg without letting it touch the floor. Repeat 10-20 times.
Make sure back stays on floor and your neck is relaxed!
Pointer Dog (Fig. 5)
This is one of the best time savers as it targets four essential
stabilizers with endurance training in one exercise! Position
yourself on hands and knees over the ball with your chin slightly
tucked. Contract the lower abdominals and pull your navel up
toward your spine. Hold this contraction throughout the exercise.
Make sure your back is flat and hips are level. Slowly lift the
right arm, thumb pointing up, hold, and then lower it. Slowly
lift the other arm, hold, then lower. Repeat for the right and left
legs. Continue to perform five lifts on each arm and leg.
Advanced version: Lift the right arm and left leg together and
hold. Make sure you are still contracting your lower abdominals!
Repeat for opposite arm/leg.
Hamstring Stretch (Fig. 6)
Research shows that in seated occupations, such as dentistry,
tight hamstrings can cause flattening of the lumbar spine.9 Sitting
on the ball (or a chair), extend one leg in front of you so the heel
rests on the floor. Ensure the knee stays straight throughout the
exercise. Keeping the back straight, pivot forward at the hips. You
should now feel a stretch at the back of your thigh. Hold 20-30
seconds or longer. Be sure to keep your head and chest up. (Don't
look at your feet!) Repeat with the other leg.
Embarking upon an exercise program requires prudence
and discretion, considering team members' predisposition to
certain muscle imbalances. Selecting improper exercises can
lead to imbalance, ischemia, nerve impingement and other
pain syndromes. Developing balanced musculoskeletal health
with a well-designed exercise program can help dentists prevent
work-related pain, avoid injuries, extend their careers and
improve their quality of life.
- Lehto TU, Helnius HY, Alaranta HT. Musculoskeletal symptoms of dentists assessed by a multidisciplinary approach. Community dentistry and oral epidemiology 1991; 19:38-44.
- O’Sullivan PB, Mitchell t, Bulich P, Holte J. The relationship between posture and back muscle endurance in industrial workers with flexion-related low back pain. Manual Therapy 2005 June 10
- McGill S. Low Back Disorders: Evidence-Based Prevention and Rehabilitation. Human Kinetics, Champaign, IL. 2002
- Rundcrantz B, Johnsson B, Moritz U. Occupational cervico-brachial disorders among dentists. Swedish Dental Journal 1991; 15:105-115.
- Valachi B. Practice Dentistry Pain-Free: Evidence-based Strategies to Prevent Pain & Extend Your Career. Posturedontics press, Portland, OR. 2008.
- Novak C, Mackinnon S, Repetitive use and static postures. J Hand Thera 10(2):151-9, April –June 1997.