Local Frontiers:
Exercise as Adjunct Therapy
for Osteoporosis
By Cheri Lieurance, MA
The risks of long-term hormone replacement therapy are driving osteoporosis
patients to ask physicians, "What else can I do to protect my bones?"
Along with appropriate pharmaceuticals, nutritional support, and lifestyle
recommendations, exercise offers an additional way to build bone and prevent
falls.
For someone with osteoporosis, a fall and resulting fracture can signal
a downward spiral to immobility and fragility. It makes sense to incorporate
a fitness program designed to build bones and keep patients on their feet.
In the long run, a fitness program featuring strength, balance, coordination,
posture, and proprioception training can translate into continued independence.
The vast majority of hip fractures are caused by falling
from standing height or less in individuals with reduced bone strength.
(1) Hip fractures are among the most debilitating of all fractures: of
those who could walk without assistance at the time of hip fracture, half
will never be able to resume this level of independence. (2)
The risk of falling increases with age and progressive frailty. Among
postmenopausal women in the United States, the likelihood of experiencing
one fall annually rises from about one in five among women aged 60 to
64 to one in three for women aged 80 to 84. (3) Poor performance in areas
such as leg strength, walking speed, step length, postural sway, proprioceptive
abilities, and even grip strength also predict a propensity to fall. (4)
The risk of injuries from falls also goes up as functional ability declines
since reflexes, agility, and upper body strength determine whether the
individual can act quickly and effectively to lessen the impact. One study
focusing on the severity of falls concluded that women who fell sideways
were more likely to suffer a hip fracture if they had weak triceps and
or were unable to grab for a nearby object. (3)
Hip fractures are not the only type of fracture caused by falls. Contrary
to the popular belief that vertebral fractures are caused primarily by
bending and lifting, falls may play a significant role in the etiology
of spinal fractures. In one study, falls produced 40 percent of clinically
diagnosed, symptomatic vertebral fractures examined; only 10 percent could
be attributed to lifting a heavy object. (5)
Building bone density through exercise has drawn considerable
clinical interest over the past 15 years as researchers strive to make
bones more fracture-resistant. In general, studies support Wolff’s
law: bone will accommodate and adapt to the habitual stresses on it. From
a purely mechanical perspective, the greater the stress, the better the
potential for building bone. Jogging is better than walking, and resistance
training is better than jogging. Forces impacting the human lumbar vertebrae
during fast walking are approximately 1x body weight, during jogging they
reach 1.75x body weight, and during weight lifting exercise done while
standing, they reach 5x to 6x body weight. (6)
Since jogging and other high-impact activities can jar a fragile spine,
researchers have experimented with ways to increase the intensity of a
walking program, such as having patients wear a weighted vest. However,
this type of weight-bearing stimulus does not produce systemic skeletal
benefits. During a one-year walking program, postmenopausal women who
wore leaded belts around their waists for four weeks developed a significant
increase in the spine but did not improve bone density of the wrist. (5)
Studies consistently show that loading must occur at a specific site for
osteogenesis to occur. (7)
What ramifications does this clinical information have
for creating an exercise program? First and foremost, an exercise program
should include resistance training. The training should ideally be of
a high-intensity type (higher weight, fewer repetitions) to improve bone
mass, if not contraindicated by the severity of the osteoporosis or its
complications. Second, the exercises should be site-specific and address
both lower and upper body, particularly the spine, hip, and forearm. Finally,
the program should encompass balance, coordination, and postural training
to prevent falls.
One form of high-intensity strength training growing in popularity is
the SuperSlow technique. This approach uses a 10-second positive and 10-second
negative and provides a relatively safe, easy-to-learn method for training
older adults. The protocol calls for the exerciser to complete a single
set of approximately six to 10 repetitions to muscle fatigue.
A full-body weight-training program provides a bone-building stimulus
to all potential fracture sites and grants patients the ability to remain
upright or catch themselves if they fall. Patients with osteoporosis need
exercises that assure strong quadriceps, hamstring, hip adductor, and
anterior tibialis muscles so they can climb stairs, negotiate obstacles,
and resist perturbations. They need upper body strength—particularly
in the wrists, triceps, and shoulders—to catch themselves if they
fall to the side, thereby avoiding a direct fall on the hip.
Along with weight training of major muscle groups, exercise programs for
osteoporosis patients should incorporate postural training and stability
training to offset the effects of kyphosis and spinal instability. Patients
with kyphosis need to strengthen the rhomboids, lower trapezius, and the
erector spinae in addition to stretching the muscles of the pectoral region
so they can achieve better spinal alignment. Elastic-band exercises for
adduction/retraction of the scapula, scapular depression, extension of
the thoracic spine, and external rotation of the humerus can target these
areas. Core stabilization exercises such as isometric abdominal contractions
and pelvic bridging help strengthen the "back-bracing" muscles:
the transverse abdominis and internal and external obliques.
Balance, coordination, and proprioception also figure in a complete osteoporosis
treatment. The balance activities can be as simple as shifting weight
from side to side, standing on one foot, and moving the upper and lower
body in opposition; or they can involve complicated skill drills, such
as obstacle courses. Because of its many weight changes and slow movement
speed, T’ai Chi provides an excellent type of balance training.
Finally, people with osteoporosis can benefit from movement or functional
training to learn proper body mechanics during everyday activities, such
as carrying groceries, bending and lifting, coughing and sneezing, and
getting out of bed. Learning to accomplish these tasks safely can result
in less stress on the spine and a lower risk of fractures. Boning Up on
Osteoporosis, a patient-oriented booklet, is a good source of this type
of information. (8)
Not all exercises are appropriate for patients with advanced
osteoporosis or fractures. Patients with vertebral fractures should avoid
exercises involving spinal flexion, rotation, or compression; side bending;
overhead presses; and any type of activities that entail a high impact,
such as jumping. Contraindicated exercises for those with a hip fracture
include abduction, adduction beyond the midline, and internal rotation.9
In addition, those with balance problems should always have some type
of support available, such as a bar.
Patients with a history of fractures should work with a physical therapist
or knowledgeable, certified fitness trainer to reduce the risk of further
injury by learning proper lifting techniques. When cost is an issue, the
fitness professional can design a program employing light weights, elastic
bands, and balls. An excellent book on home exercises is Exercises
for Osteoporosis by Dianne Daniels.10 The National Osteoporosis Foundation
also sells a video called "Be Bone Wise" that leads the viewer
through a series of strength-training exercises.
A diagnosis of osteoporosis can leave patients fearful and despairing
as they anticipate a future of physical decline. With guidance from physicians
on how to exercise safely and effectively, they can look forward to years
of strength, mobility, coordination, and independence.
Prepared with help from Amy Shaw, MD.
References
- J. Melton et al, "Biomechanical aspects of fractures,"
Osteoporosis: Etiology,
Diagnosis and Management, Raven Press (1988). - Institute of Medicine, "Osteoporosis," The Second Fifty Years: Promoting Health and Preventing Disability, National Academy Press (1990).
- M. Neavit et al, "Type of fall and risk of hip and wrist fractures," J Amer Ger Soc, 41:1226-1234 (1993).
- M. Neavit et al, "Risk factors for recurrent nonsyncopal falls," JAMA, 261:2663-2668 (1989).
- C. Cooper et al, "Incidence of clinically diagnosed vertebral fractures," J Bone & Min Res, 7:221-227 (1992).
- R. Swezey, "Spine update: exercise for osteoporosis—is walking enough?" Spine 21;23:2809-2812 (1996).
- D. Kerr et al, "Exercise effects on bone mass
in postmenopausal women are site-specific and load-dependent,"
J Bone & Min Res, 11;2:218-225 (1996).
National Osteoporosis Foundation, Boning Up on Osteoporosis (2002). - J. Weller, "Osteoporosis and exercise," IDEA Personal Trainer, Nov-Dec:35-44 (2002).
- D. Daniels, Exercises for Osteoporosis, Hatherleigh Press (2000).
Ms. Lieurance is a certified exercise specialist at 3D Fitness in Santa Rosa.
Sonoma Medicine, Volume 54, Number 2 (Spring 2003).
