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Christina Beaudoin, assistant professor of sports medicine,
is interested in health and diet issues and especially the
effects of diet and physical activity levels on bone density
in adolescent and middle-aged women.
Her current research was prompted by a Harvard University
study that showed a higher incidence of fractures in adolescent
girls who drank more carbonated drinks and were more active
than a control group. The study had limitations in that it
was based on self-reported, retrospective data.
To build on that study, Beaudoin with Janet Whatley Blum,
assistant professor of sports medicine and a nutritionist,
conducted a study of 50 women aged 20 to 45 and found that
those who consumed more carbonated drinks didn't show less
bone density. She did see greater density in association with
higher dairy consumption, but this was also associated with
higher levels of body fat. This preliminary study, which was
supported by a Faculty Senate award, will require follow-up
studies to try to clarify causes and results.
In addition, Beaudoin would like to reproduce the Harvard
study with 13 to 18 year old subjects. She'd like to add to
the basic study design collection of data on the correlation
of dietary choices with a subject's self-esteem level to see
if eating patterns are affected by body image.
Besides her research efforts, Beaudoin is involved in a
summer camp that combines instructional sport activities with
drug and alcohol abuse prevention, health and nutrition education,
and career and educational opportunities. A grant she was
awarded by the National Youth Sports Corporation (NYSC) for
$47,500 will support a five week, half-day sports camp that
is open to Greater Portland youth, 10 to 16, from economically
disadvantaged backgrounds. The program, which will be one
of about 200 in the country supported by the NYSC, will run
through July.
Godard Helping Ill, Elderly
In the Costello Sports Complex, a stream of senior citizens
are measured, tested for strength and thrown off balance.
But researcher Michael Godard's aim is not to torture the
elderly but to help them.
Godard, assistant professor of sports medicine, hopes his
tests of senior citizens in USM's Human Performance Lab will
yield more knowledge on the effects of aging and heart disease.
His work may even indicate how to reverse decline in physical
capability.
Godard studies the impact of congestive heart failure on
muscle tissue and the effects of activity or inactivity on
protein structures in muscle fibers. He also studies the ability
in older people to increase the balancing reflex.
In normally active people during their prime years, Godard
explains, there is a mix of fast twitch and slow twitch muscle
tissue. Fast twitch tissue allows people to move suddenly
and quickly, as in a reflex action, while slow twitch muscle
helps the body sustain activity since it tires less quickly.
As people age and generally become less physically active,
their bodies replace fast twitch tissue with slow twitch.
As a result, older people tend to have slower reflexes and
are less able to move quickly.
Heart patients, however, have the opposite pattern of muscle
tissue. This seemingly surprising result is caused by the
lower rate of oxygen reaching muscle tissue in heart patients.
Because fast-twitch muscle tissue requires less oxygen, heart
failure causes muscle tissue to convert to fast-twitch tissue.
This tissue fatigues very quickly, so heart patients lose
some of the functionality of their muscles. They become less
able to engage in activities, especially physically demanding
ones, for any length of time.
Godard tests whether muscle components can be reversed through
activity level by comparing active and non-active heart patients.
He recruits his research subjects through a collaboration
with Dr. Joseph Wight, a Portland cardiologist who screens
heart patients to find candidates that fit Godard's criteria
for the study. Dr. Mark Bouchard, another local doctor, recruits
and screens subjects for control groups. The subjects in both
the active and inactive heart patients, and similar control
groups made up of non-heart patients, range in age from 45
to 75, with a mean age in the 60s. The heart patients have
to be ambulatory and fairly functional to participate.
Godard determines the quality of the muscle by measuring
the size of a subject's thigh muscle through a medical scan
and then divides the size by the strength of the thigh muscle,
determined by using a measurement of kicking strength. He
uses a biopsy technique to draw a muscle sample from below
the skin that is about half the size of a pinky nail and contains
some 1000-1500 single muscles fibers.
Under a microscope, Godard can dissect out these single fibers
and through a lab technique can determine whether the fibers
contain slow-twitch or fast-twitch proteins, or both if the
tissue is in transition.
A comparison of the active and inactive heart subjects with
like control groups indicates that physical activity has a
definite effect on muscle fiber make-up. Godard hopes to
complement this research with future longitudinal research
that would study the impact of increasing activity levels
in subjects.
Another research project Godard has underway tests the ability
of the elderly to increase their capability to balance. Over
an eight week period, Godard's subjects, all of whom are over
70 years old, shift their weight to keep their balance as
they stand on a tilting platform. The subjects are prompted
to shift their weight by gazing at a computer screen that
indicates when they've got the tabletop in balance by showing
a dot that, through their movements on the platform, is guided
into a box. Over time, the difficulty of balancing is increased.
As the subject responds to the visual stimuli, the computer
assesses the coordination of his or her nervous system with
the upper and lower leg muscles. Through repetition, Godard
says, the neuromuscular pathways become more refined. Godard
has found that all his subjects, participating three times
a week over the eight weeks, had their ability to balance
increase by at least 100 percent, and some as much as 250
percent.
Godard's research is supported by USM's Bioscience Research
Institute of Southern Maine funds. He uses BRISM lab equipment
for biochemical analyses, and equipment purchased by the Sports
Medicine program to measure physical performance.
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