Highlights from American College of Sports
Medicine Annual Meeting and World Congress
on Exercise is Medicine® 2015
ca
Carol A. Harrison, M.Ed
Senior Exercise Physiologist
Highlighted Topics for Discussion
• ACSM Roundtable Pre-participation Exercise
Screening Guidelines and Proposed Changes
• Current Research in Exercise Immunology
• Is it Time for Personalized Exercise
Medicine?
• Wired for Health and Physical Activity
ACSM Roundtable Pre-participation Exercise
Screening Guidelines and Proposed Changes
ACSM Roundtable convened in June 2014 to:
• Safety of exercise
• Identify those at risk for serious cardiac events during exercise
• Review current literature
• Update recommendations and discuss the need for change based on current
findings
What we know:
• Exercise is relatively safe
• Many health benefits
• Cardiac events during exercise are rare
• Adverse events usually preceded by signs and symptoms
• Risk of cardiac event decreases with increased overall fitness
ACSM Roundtable Pre-participation Exercise
Screening Guidelines and Proposed Changes
Current recommendations overly conservative resulting in:
• Perceived barrier to starting an exercise program
• Reluctance to advance exercise program when needed
• Unnecessary burden on the healthcare system
• Financial burden on individuals committed to starting an exercise
program
Roundtable participants from:
• Risk assessment
• Preventative cardiology
• Public health
• Exercise physiology
• Geriatrics
• Health and fitness
ACSM Roundtable Pre-participation Exercise
Screening Guidelines and Proposed Changes
New evidence informed model for pre-participation screening based
on:
• Current level of physical activity (exercise)
• Presence of signs and symptoms or known cardiac, metabolic, or
renal disease
• Desired level of intensity
Current evidence suggests that approach should be individualized.
ACSM Roundtable Pre-participation Exercise
Screening Guidelines and Proposed Changes
1. CVD risk profile no longer part of the decision making process when
deciding whether to refer for medical clearance or not. No longer
classification of individual into a low, moderate or high risk category.
2. No longer making recommendation for a medical exam or exercise
stress test. The recommendation is for medical clearance only. It is
up to the healthcare provider to determine the necessity of these
assessments based on patient records and current condition. Do
they need it?
3. No longer automatically recommending those with pulmonary
disease get medical clearance before exercising. Why? In itself, it
does not increase risk for a cardiac event during exercise.
Again, presence of signs and symptoms critical in making assessment.
ACSM Roundtable Pre-participation Exercise
Screening Guidelines and Proposed Changes
New guidelines released in MSSE November 2015
ACSM Guidelines for Exercise Testing and Prescription
10th edition to be released in 2017 (?)
Individuals looking to test for ACSM certification will be notified (on the
certification website) when new guidelines take effect.
Highlights of Current Research in Exercise
Immunology
The new sub-discipline in exercise physiology of exercise immunology
emerged during the 1980’s.
Exercise immunology’s primary focus is on how exercise effects immune
function and what are the consequences of that effect.
What are the mechanisms of the effect?
Does the timing of the exercise enhance or is it detrimental in the immune
response?
Highlights of Current Research in Exercise
Immunology
Enhancing Virus and Tumor-specific Immunology with Exercise
Richard J. Simpson, Associate Professor, University of Houston, Houston, TX
Area of interest presented:
• How does the immune system respond to a single bout of exercise.
• More specifically, how exercise can improve immune response to viruses
and certain tumors.
Highlights of Current Research in Exercise
Immunology
We know that leucocytes increase dramatically in response to exercise.
There is an intensity dependent mobilization of total lymphocytes
immediately post exercise followed by lymphocytopenia during the early
stages of recovery ( J curve).
During exercise there tends to be a mobilization and high proliferation of
lymphocytes( CD8+ T cell subtype called KLRG1, has previously encountered
an antigen, has memory) in the peripheral blood flow.
The mechanism by which exercise elicits this response is mediated by
catecholamines.
Catecholamine (epinephrine, norepinephrine) concentrations increase
markedly during exercise.
Highlights of Current Research in Exercise
Immunology
Can this knowledge now be expanded to look a viral infections and
cancer immunotherapy?
The cytomegalovirus (CMV) is a very prevalent herpes virus
• CMV increases as we age
• CMV is asymptomatic
• In the immuno-compromised individual it can be fatal.
• It can be mobilized with exercise as well as the viral specific and tumor
antigen specific T cells (KLRG1).
Highlights of Current Research in Exercise
Immunology
Exercise profile:
• Cycling
• Steady state at 10% about previously measured lactate threshold
• Duration of 30 minutes
Exercised above lactate threshold to insure release of catecholamines.
Viral and tumor antigen specific T cells are increased in the blood
compartment during this exercise.
Results:
• Exercise had a dramatic effect on the expansion of the CMV viral
specific T cells observed in the blood.
• Under non-exercise conditions, 21 days to grow same number of
immune cells observed after 8 days immediate post-exercise
expansion.
Highlights of Current Research in Exercise
Immunology
How can this research now be expanded to cancer immunotherapy
treatment?
• Use of immediate post-exercise cells may dramatically reduce
time for donor immune cell expansion.
• Given the fact that these exercise cells are highly cytotoxic, can
this method cause an increase in the incidence of graft versus
host disease after stem cell transplant? Still investigating.
• Evidence has shown that it is fairly safe for healthy donors to
exercise through apheresis thus increasing time for gathering and
expansion of donor immune cells.
Highlights of Research in Research in Exercise
Immunology
Exercise, Colitis, and the Gut Microbiome
Jeffrey A. Woods, Professor, University of Illinois, Urbana, IL.
Present in the gut we have:
• Feces
• Microbiota (several bacterial species, some
harmful, some not).
• Epithelial cells with short half lives
• Stem cells that mature into epithelial cells, etc.
• Immune cells
• These cells are combined by barrier tight structure layers
There can be a breach between cell layers separating micro-organisms and an
entering in of cells where they should not be, thus causing a pro-inflammatory
state and an immune response.
Highlights of Current Research in Exercise
Immunology
How does exercise effect the gut?
Physical activity in the form of regular exercise can protect against colon
cancer to the tune of a 25 to 30% reduction in colon cancer mortality.
Problems arise with the presence of chronic and/or excessive inflammation
leading to many pathologies including ulcerative colitis (UC) which can lead
to colon cancer.
Can regular exercise alter inappropriate information in chronic and/or
excessive inflammation and improve the consequences associated with
pathological inflammation?
Highlights of Current Research in Exercise
Immunology
Can exercise attenuate ulcerative colitis (UC) in mouse?
• Forced treadmill running 6 weeks as opposed to a sedentary mouse
control
• Dextran sulphate sodium (DSS) applied 2% in water as opposed to water
only group.
• DSS disrupts the gut barrier function initiating inflammation in mice.
Exercised 6 weeks, 5 days weekly, 40 minutes a day, for a total of 30 exercise
sessions.
This type of treadmill training has been shown to decrease inflammation in
adipose tissue.
Highlights of Current Research in Exercise
Immunology
Results:
• Forced treadmill running induced mortality and morbidity.
exacerbating the inflammatory response in DSS treated mice.
• Water-fed only mice did not experience exaggerated inflammatory
response.
• Forced treadmill running perceived as excessively stressful. Proven by
examination of adrenal gland (hypertrophy during excessive stress)
and thymus gland (atrophy during excessive stress).
Is all exercise the same? Can excessive stress “nullify” the potential
protective benefits of exercise?
• Procedure repeated using voluntary wheel running.
Results:
• No deaths, little to no diarrhea, weight loss minimal.
Highlights of Current Research in Exercise
Immunology
Conclusions?
• There are apparent benefits to wheel running as opposed to forced
treadmill running.
• Cytokine expression examined in the distal colon of wheel runners (TNFα,
IL-6). Wheel running attenuates the inflammatory response in the distal
colon suggesting protection against DSS induced colitis.
• Adrenal and thymus glands examined in wheel runners. No difference in
normal weight observed suggesting that the mice did not perceive wheel
running as stressful.
• Exercise mode and circumstances under which it is undertaken appear to
make a difference in the potential benefits derived.
Highlights of Current Research in Exercise
Immunology
Further study from a microbiome view:
• Voluntary and forced exercise may alter the community structure of the gut
microbiota
• Voluntary and forced exercise can alter the bacteria taxa that may be
implicated in the pathogenesis of UC.
• Increased concentration of gram negative (pathogenic) bacteria seen in forced
treadmill runners as opposed to wheel runners.
• May be correlated changes in the gut microbiota that can account for the
responses to DSS treatment between forced (stressful) treadmill running and
voluntary wheel running. What are they specifically?
• Exercise can be used to reduce inflammation associated with chronic
inflammation in irritable bowel disease.
Is it Time for Personalized Exercise Medicine ?
Evidence Supporting Inter-individual Response to Cardiorespiratory
Fitness in Response to Exercise Dose
Tim Church, Pennington Biomedical Research Institute, Baton Rouge, LA.
What we have believed:
• Every 1 MET increase in activity is associated with a 13% reduction
in risk for all cause mortality.
• Every 1 MET increase in activity is associated with a 15% reduction
in cardiovascular disease (CVD) mortality.
What we now observe:
• Fitness is relative.
• Potential benefits associated with beginning fitness level.
• Moderate to high fitness, 1 MET increase offers no benefit
• Low fitness, 1 MET increase 20-30% improvement in all cause
mortality, 20-30% reduction in CVD risk.
Is it Time for Personalized Exercise Medicine?
Highlighted Dose Response to Exercise in Women (DREW) study
Cooper Institute, yr. 2001-2006)
Investigated the effects of different volumes of exercise training on CRF and
SBP
Volume defined as total energy expenditure per week (kcal/kg/week or kkw)
• 464 women
• BMI 25-43
• SBP 120-159.9 mmHG
• Exercised at 50% of peak VO2
• Cycle ergometer and treadmill
• 6 month intervention
• Randomized to non-exercise, 4 kkw, 8 kkw, 12 kkw
Is it Time for Personalized Exercise?
Results:
• Absolute VO2 (L/min) increased in exercise group overall compared to control group
by 4.2% (4kkw), 6.0% (8kkw), 8.2% (12kkw).
• No significant change in SBP
• Control group decreased (-1.7%)
There was significant individual variability in response across all exercise groups.
Some responded well while others responded poorly or not at all.
• 4kkw
• 8kkw
• 12kkw
46% nonresponders
24% nonresponders
19% nonresponders
The smaller the exercise volume the greater the number of nonresponders. But high
numbers of nonresponders seen at all 3 dosage levels.
Add resistance training? Add interval training? Personalize mode to match likelihood
of response?
Is it Time for Personalized Exercise?
Robert Ross, Professor
Queen’s University, Kingston, ON, Canada
• Individual response to exercise has been neglected.
• We should focus on the dynamic interaction between intensity and
volume.
• High Amount High Intensity appears to achieve favorable CRF in all
subjects, but still in varying degrees.
• If we are going to fix the amount of exercise and alter intensity,
multiple assessments of CRF ( every 4 to 6 weeks) must be done
and the training program adjusted in response to the physiological
changes in the individual.
• It is possible to do exercise of varying amounts and intensities and
see no results.
Is it Time for Personalized Exercise?
Claude Bouchard, Professor
Pennington Biomedical Research Institute, Baton Rouge, LA.
What would personalized exercise medicine do?
• Treat that person as a unique biological entity.
• Understand individual’s unique makeup so we can possibly predict how
they will respond, risk for cardiac event, risk for joint and/or skeletal
muscle injury.
• Tailor the exercise to the person and not the group.
Is it Time for Personalized Exercise Medicine?
Claude Bouchard, Professor
Pennington Biomedical Research Institute, Baton Rouge, LA.
What is needed for successful personalized exercise?
What we need are diagnostic tools to achieve personalized medicine.
How do we develop diagnostics?
• Gene expression profiling
• Genomic markers powerful in contribution to diagnostics
• Metabolic profiling
• Need large and powerful studies (of the pharmaceutical type) which may
not be likely because they depend on tissue not generally used for diagnostic
purposes (muscle and adipose tissue). Very expensive.
Wired for Health and Physical Activity
Edward Melanson, Professor
University of Colorado, Denver, CO.
Estimating Energy Expenditure using Body Worn Direct Calorimetry Device
Nutrients + O2 → ATP + Heat + CO2 + H2O (simple energy expenditure equation)
Indirect calorimetry (what we presently use in our physiology labs): Heat and gas
exchange (CO2 exhaled in relation to O2 consumed) is directly proportionate to
energy expenditure.
Direct calorimetry is the measurement of the actual heat produced by an individual
in a small closed chamber.
Metalogics® has developed the Personal Calorie Meter (PCM) for direct
measurement of energy expenditure (calories burned).
Wired for Health and Physical Activity
DirectCAL™ directly measure all the calories your body burns. It does this by accurately
measuring the heat that is generated by your body. As seen in the illustration below,
the patented sensor measures all four forms of heat that flows from your body (heat
flux), including heat flows from conduction, convection, radiation and evaporation.
Wired for Health and Physical Activity
The sensing band measures all forms of heat generated by your body. Data is
transmitted wirelessly from the armband to the portable read-out so you know
instantly the amount of calories you are burning.
Wired for Health and Physical Activity
Advantages of PCM:
• They are sensitive to activities not detected by activity monitors.
Ex: Accelerometers cannot measure resistance training efforts.
• They provide immediate results.
• They can easily be hidden under clothing.
• May possibly be used to personalize exercise prescription.
Disadvantages of PCM:
• Wearing heavy clothing may skew output.
• Sleeping under heavy covering may produce erroneous output.
• Obesity
• Not accurate over brief periods of time as the heat is lost.
Highlights from American College of Sports
Medicine Annual Meeting and World Congress
on Exercise is Medicine® 2015
Many thanks to the Center for Energy Balance in Cancer
Prevention and Survivorship