Monday, February 23, 2009

physical therapy for PD patients

The traditional view of how to treat people with
neurodegenerative conditions is that exercise has little
or no effect, or that it can actually worsen the disease!
However, recent research in both humans and
animal models suggests that physical therapy — including
gait and balance training with external cues
to improve walking, resistance training for the lower
extremity muscles, balance training, and regular exercise
— can be an important component of an exercise
programthatmay help improve or hold the signs
and symptoms of Parkinson’s disease (PD) at bay.
Gait and Balance
Gait and balance impairments are cardinal symptoms
of PD. If left untreated, impairment in walking
or balance can lead to falls, fractures, hospitalization
and loss of independence. In fact, roughly 40 percent
of nursing home admissions are preceded by a fall,
and falls occurmore frequently in people with Parkinson’s
than they do among other individuals.
Recently, a large number of studies have focused
on improving gait in peoplewith Parkinson’s through a
training exercise known as “cueing.” People with PD
sometimes have difficulty generating internal cues to
take a step. Theymay “freeze” while standing or walking,
which in turn can cause falls and injuries. External
cues, such as providing a cane to trigger a stepping
movement, placing horizontal lines on the floor, giving
instructional cues (such as asking the person to “take
long steps”) or walking to a rhythmicmetronome, can
all improve a person’s stride length and walking velocity,
and reduce shuffling and freezing.
In one such study — cueing training was used to
improve walking in participants’ home environments.
The results, thoughmodest, showedmeasurable improvements
in gait and balance, as well as reduced
freezing and greater confidence to carry out functional
activities. However, after the training ended,
the improvements were gradually lost, reminding us
that it is important to continue exercising if those improvements
are to be long lasting.
Recent research has also suggested that a person
with PD needs to exaggerate his or her effort (amplitude)
of movement for it to have the same impact of
normal movement in a person without PD.
Improving Strength
Studies have generally shown that exercise improves
speech and swallowing, posture, tremor, dexterity,
cognition and depression. Other studies have
shown that treadmill training, and lower extremity resistance
and balance training, can be effective at improving
muscle strength, gait and balance.
There has been considerable interest recently in
therapies designed to increase muscle mass, known
as “muscle hypertrophy.” Several studies have shown
that individuals who improved the size of their muscles
also demonstrated improvements in functional
activities such as climbing or descending stairs or balancing.
Muscles shrink when they are not used; conversely,
muscle tissue increases in girth with intense
resistance training. As we age, we often become
more sedentary and muscle loss becomes inevitable
— underscoring the need for exercise.
In the late 1980s, studies began to show that older
adults—many already in their 80s and 90s, and some
of them in nursing homes—could improve strength,
muscle bulk and function in response to high-intensity
resistance training. Despite this evidence — and
because some researchers and therapists believed
that resistance training might itself increase muscle
stiffness—strengthening was not advised for people
with PD out of fear that it might be harmful.
More recent studies have further challenged this
view. Results of one study of people with mid-stage
Parkinson’s suggest that high-intensity resistance
training results in a six percent increase inmuscle volume,
17 percent improvement on how far participants
could walk in six minutes, and a 22 percent and 13
percent improvement in stair descent and ascent
time. In another study, high-intensity resistance training
for the lower extremity muscles was found to im-

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