February 28 - 29, 2008 Advisory Committee Meeting
Older Adult Summary
Miriam Nelson, Ph.D., presented summary conclusions surrounding adults and
older adults and the following health outcomes: Bone health (adults and older
adults), joint health (adults and older adults), muscle health (older adults),
functional health (older adults), falls (older adults), mental health (adults
and older adults).
For bone health, the association between physical activity and reduction in
hip fracture the data is Type 3a of moderate strength level and weak evidence
for vertebral fractures. At the highest level of physical activity the risk
reduction ranges from 36 – 68%. More than 4 hours per week of walking, 2 – 4
hours per week of leisure time activity, 9 to 14.9 MET hours per week are all
associated with 36 – 41% risk reduction. The data also suggests a reasonable
Type 2a, moderate strength evidence supports the conclusion that exercise
training can increase bone or attenuate bone loss. Weight bearing endurance
training for the hip and spine and resistance training is effective based on
moderate-to-high intensity activity 3 – 5 days per week with 30 – 60 minute
sessions. The dose-response relationship has not been adequately tested.
Individual RCTs support basic science findings that intensity of loading forces
is a key determinant of the skeletal response. Walking-only meta-analysis was
found to be effective on the spine.
The data supports the following conclusions on joint health in adults and
older adults. The evidence that physical activity prevents osteoarthritis is
supported by Type 3a, limited and weak level evidence. Both endurance training
and resistance training provide disease-specific benefits for persons with OA,
RA and Fibromyalgia and is supported by Type 1, strong evidence. The effects of
physical activity in delaying the onset of disability in people with OA are
supported by weak data. The dose response relationship has not bee studied.
In functional health the evidence that physical activity prevents or delays
the onset of functional limitations is supported by Type 3a, strong evidence
suggesting a 40% risk reduction. Most of the evidence comes from walking
activities. There appears to be a dose-effect. The evidence that physical
activity helps maintain or improves functional ability includes Type 1, moderate
strength evidence. Most of the evidence is from exercise programs that include
moderate-intensity walking and muscle-strengthening activities. There is
limited, Type 1, evidence that physical activity doses of less the current
guidelines are still beneficial. It is unclear there is a dose-response as it
has not been tested.
The level of evidence that high-intensity muscle strengthening activities can
preserve or increase skeletal muscle mass, strength, power and intrinsic
neuromuscular activation consists of Type 1, strong level data. The benefits are
similar in both men and women. There is strong evidence that regular muscle
strengthening activities can provide benefit. There is moderate level evidence
that endurance type activities do not increase muscle mass or quality, but may
attenuate the rate of loss with aging and preserve function. There is strong
evidence of a dose-response with the greatest gains in muscle mass and muscle
strength experienced with higher-intensity protocols.
There is Type 1 and 3a, strong evidence that physical activity reduces the
risk of depression and cognitive decline in adults and older adults. There is
limited evidence that activity reduces distress, anxiety and improves sleep.
Most of the evidence for benefit suggests a program consisting of 3 – 5 days per
week of 30 – 60 minute sessions of moderate-to-high intensity activity. There is
moderate level data that suggests a dose-response relationship.
The level of evidence that supports the conclusion that physical activity
programs that include balance, strength training and walking reduces the risk of
falls by 30% consists of Type 1, strong data. The greatest benefits are seen in
people at the greatest risk for falls. Most evidence suggests a program that
includes moderate intensity strength and balance training 3 days per week with
30 minute sessions with additional encouragement to walk 30 minutes 2 times a
week. It is unclear whether there is a dose-response relationship as it has not
Overall, to reduce injuries it is important to progress exercise intensity
and volume slowly. Older adults are disproportionately at risk for premature
all-cause mortality, CHD, CBD, Type 2 Diabetes and stroke. For this reason, the
adult recommendations apply to older adults.