ES 4700
BENEFITS OF PA AND
CHRONIC CONDITIONS
STRONGLY
ASSOCIATED WITH
PHYSICAL INACTIVITY
Chapter ??
Physical Activity and Fitness Terminology
• Physical Activity (PA)
– Any bodily movement produced by the contraction of skeletal
muscles that results in a substantial increase in caloric requirements
over resting energy expenditure
• Exercise
– A type of PA consisting of planned, structured, and repetitive bodily
movement done to improve and/or maintain one or more
components of physical fitness
• Physical fitness
– a set of attributes or characteristics individuals have or achieve that
relate to their ability to perform PA and activities of daily living
• Capacity to do physical work without undue fatigue
Public Health Perspective for
Current Recommendations
• More than 20 yr ago, the American College of Sports Medicine
(ACSM) in conjunction with the Centers for Disease Control and
Prevention (CDC), the U.S. Surgeon General, and the National
Institutes of Health (NIH) issued landmark publications on PA and
health.
– Do you remember the year?
• What are the amount and intensity of PA needed to improve
health, lower susceptibility to disease(morbidity), and decrease
premature mortality.
• Documented the dose-response relationship between PA and
health (i.e., some activity is better than none, and more activity, up
to a point, is better than less).
Public Health Perspective for
Current Recommendations
• Two important conclusions from the Physical Activity
Guidelines Advisory Committee Report that influenced the
development of the PA recommendations are the following:
• Important health benefits can be obtained by performing a
moderate amount of PA on most, if not all, days of the
week.
• Additional health benefits result from greater amounts of
PA. Individuals who maintain a regular program of PA that
is longer in duration, of greater intensity, or both are likely to
derive greater benefit than those who engage in lesser
amounts.
Estimated Dose-Response Curves for
Atherosclerotic CVD
Public Health Perspective for
Current Recommendations
• Physical inactivity: a global pandemic that has
been identified as one of the four leading
contributors to premature mortality
• Globally, 31.1% of adults are physically inactive.
• In the US:
– 50.9% of adults meet aerobic activity guidelines.
– 30.4% meet muscle strengthening guidelines.
– 20.5% meet both the aerobic and muscle strengthening
guidelines.
Sedentary Behavior and Health
• Prolonged periods of sitting or sedentary behavior
are associated with deleterious health
consequences independent of PA levels.
• Self-report NHANES data indicate 4.7 h · d−1 of
sitting time.
• Objectively measured accelerometer data indicate
~8.0 h · d−1 sitting time.
• Regardless, high levels of sedentary behavior can
be detrimental to ones’ health.
> 17,000 adults, 1832 deaths
over avg follow-up of 12 yrs
Katzmarzyk et al.,
2009
From Ekelund
et al., 2016
The effects of
sitting for 8 hrs
per day are all
but eliminated
in those who
are active for at
least 420
min/week
Health Benefits of Regular PA and
Exercise
• Evidence to support the inverse relationship
between regular PA and/or exercise and premature
mortality, CVD/CAD, hypertension, stroke,
osteoporosis, T2DM, metabolic syndrome
(Metsyn), obesity, 13 cancers, depression,
functional health, falls and cognitive function
Health Benefits of Improving Muscular
Fitness
• The health benefits of enhancing muscular fitness
(i.e., the functional parameters of muscle strength,
endurance, and power) are well established.
• Higher levels of muscular strength are associated
with a significantly better cardiometabolic risk
factor profile, lower risk of all-cause mortality,
fewer CVD events, lower risk of developing
physical function limitations, and lower risk for
nonfatal disease.
Conditions Linked to Excessive
Sedentarieness
• Cardiometabolic
– HTN
– Dyslipidemia
– Atherosclerosis
• Injury to vessel wall
• Inflammatory immune respons
• Oxidizable lipid
– Obesity
– T2DM
Conditions Linked to Excessive
Sedentarieness
• Musculoskeletal
– Arthritis
– LBP
– Osteoporosis
• Cancer
– ~13 types have been strongly linked to inactivity
Conditions Linked to Excessive
Sedentarieness
• Mental Health
– Depression
– Anxiety
Positive Effects of Exercise on
Hypertension
• Average reduction of 5 to 10 mmHg in
resting BP
• Potential mechanisms
– Alteration in renal function
– Decrease in plasma norepinephrine
– Increase in circulating vasodilator substances
Positive Effects of Exercise on
Dyslipidemia
Benefits to blood lipids
– Decreased concentrations of small-dense LDL
particles, and lower LDL-C
– Higher HDL-C concentrations
– Lower triglyceride levels
– Reduced postprandial lipemia
Exercise Programming and Effects
• Exercise for both HTN and dyslipidemia
responds to an increase in total energy
expenditure or exercise volume
– 150 to 300 min/week of moderate to vigorous activity
if no other chronic conditions
• Similar recommendations with chronic disease, but “selfpaced” PA
• Weight loss will likely increase benefits
Overweight, Obesity, Prediabetes, and
Type 2 Diabetes
• Primary recommendation for diabetes is
weight loss and increased physical activity
• Effects of Obesity on Exercise Response
– Elevated mechanical and thermal stress
– Increase oxygen cost of PA
• Any given ml/kg/min with elevated body mass  increased
gross VO2 (l/min)
Overweight, Obesity, Prediabetes, and
Type 2 Diabetes
•
Primary recommendation for diabetes is weight loss and increased
physical activity
•
Individualized exercise program important
– Cardiac conditions
– Silent ischemia
– Likelihood of difuse ACVD
– Exaggerated pressor response
– Neuropathy: impaired proprioception, skin concerns and foot trauma
– Retinopathy: impaired visual acuity, fall risk
Exercise Programming
Optimal goal of ≥ 250 min/week of moderate
activity
– Obesity with disability or high comorbid burden
indicates supervision of a skilled exercise specialist
– Diabetes may need to start at light intensity and
gradually increase to goal
Arthritis and Back Pain
• Osteoarthritis: biomechanical failure of the
articular cartilage
• Rheumatic arthritis (autoimmune disease)
mediated inflammatory joint issue
– Exercise when a patient has an acutely painful joint
induces neuromotor inhibition to cause a reduction
in muscle force
• It can be challenging to distinguish between neuromotor
inhibition and general muscle dysfunction in arthritis
patients
– Therapeutic exercise can restore muscle function
Exercise and Arthritis
• Exercise training
– Can reverse neuromuscular inhibition
– Build and strengthen muscle
– Can improve joint integrity
– Can increase the strength: weight ratio and reduce
severity of symptoms
– Reduces inflammation
• Exercise is a potent anti-inflammatory
Exercise Programming
• Mild arthritis patients should follow ACSM
guidelines
• Arthritis with disability or limited
functioning
– Weight-bearing, repetitive endurance exercises
– Core strength with attention to balance issues
– Moderate-intensity walking is appropriate
Osteoporosis
• Condition is result of decreased bone
matrix and mineral content
– Type I: postmenopausal condition secondary to
estrogen deficiencies
– Type II: related to aging; not sex specific
• Management aimed at prevention involving
exercise and diet
Exercise Programming
• Osteopenia (Z-scores between -1 and -2.5)
– ACSM Guidelines
• Osteoporosis (Z-scores below -2.5)
• Considerations include twisting and highimpact movements, extreme flexion and
extension of spine