Exercise Testing and Prescription
· Exercise Training
o 1982 – physiology of bodily exercise – training is a series practices the object of which is to render a man or animal as completely and quickly as possible, fit for the performance of a given work
o Can be intellectual, skill acquisition, or “tool”
o Exercise training VS. physical activity (PA)
§ 1995 ACSM and CDC published benefits of moderate PA
· 30 min of brisk walking/mod activity improves QOL
§ Dept of Health and Human Services
· 2004 – 40% of 18 yo and older get no PA (not even for 10 min)
o 22% engage in vigorous PA
o How do we help our patients increase PA?
§ Education
· Disease, diagnosis, disability
§ Exercise Prescription
· How
· Frequency, intensity, duration
· Modality
o The conundrum of starting to exercise
§ Medical clearance/evaluation
· Consider whether the individual is low, moderate, or high risk
o High risk for medical evaluation and determination of exercise supervision
o Exercise prescription
§ HR or BP limits, blood sugars, ortho issues, neurologic deficits
o Baseline for comparison
o Risk factor assessment
§ CAD
§ Graded exercise test
· Max effort is given using treadmill (most common), cycle ergometer, or other devices
· EKG (ECG)
o Baseline reading for HR and rhythm
o Monitor changes in cardiac parameters (ischemia)
o Abnormalities or signs suggestive of CV, pulmonary, or metabolic disease
§ SOBOE (mild exertion), syncope, tachycardia, pain in chest, jaw
o Blood pressure
§ Normal vs. abnormal
· Exercise Prescription
§ Mode (Type)
· Aerobic or strength
§ Frequency of participation
· 3-5 days/week
§ Duration of exercise bout
· 20-30 min; progress to 45-60 min
§ Intensity of exercise
· 55-90% HR max
· Karvonen formula = [208-(0.7*age)]
§ Consider goals of individual
· Goals set by PT work with pt goals and your ex Rx
o Monitor individual’s workout and progress
§ Training HR**
· 55-90% HR max
§ Rating of perceived exertion (RPE)
· Individual’s self-perception
· RPE of 12-13 or 15-16
§ Metabolic equivalents (METs)
· Based on assumption that 1 MET = 3.5ml/kg/min
· Unable to take into account different metabolic efficiency
· Used often in exercise Rx and cardiac rehab
o All programs should consist of:
§ Warm-up followed by stretching
§ Endurance training
§ Strength/resistance training
§ Flexibility
· Yoga, stretching, Tai Chi
§ Recreational activities
o Resistance Training
§ Muscle strength (3 sets), Power (high wt quickly, low reps) and Endurance (high reps, low wt)
§ The Difference?
· Muscular strength
o Max force that muscle or muscle group can generate
o 1 rep max or isokinetic training
· Muscular Power
o Rate of work performance
o Power = force*velocity
· Muscular Endurance
o Capacity to sustain repeated Mm contractions
o Aerobic Power
§ Rate of energy release by cellular metabolic processes
§ Depends on availability and involvement of oxygen
§ Assess by VO2max
§ Critical power – fatigue threshold (stay below that, you could potentially continue for forever)
o Anaerobic power
§ Rate of energy release by cellular metabolic processes
§ Function without oxygen
§ Assess with Wingate, shuttle tests
· General Principles of Training
§ Principle of individuality
· Athletes, clinical population, impairments, disability, motivation and goals
§ Principle of Specificity
§ Principle of Reversibility
§ Principle of Progressive Overload
· Pertains to both aerobic and anaerobic training
§ Principle of Progression
· Gradual cycling of specificity, intensity, and volume or training
· Peak levels of performance for competition
o Resistance Training
§ Isometric or static contraction
§ Isotonic
· Set load; but speed can be variable – typically performed on isokinetic dynamometer
§ Dynamic
· Limited by the weakest point in AROM; strongest point never taxed
§ Eccentric training
· Emphasizes the eccentric phase of contraction
· Ability to resist force and essential to hypertrophy
§ Isokinetic
· Keeps movement speed constant despite % effort
· Angular velocity
· Biodex, Cybex
§ Plyometrics
· Bridge the gap between speed and strength using stretch reflex
§ Electrical Stimulation
o Interval training
§ Can be used for anaerobic or aerobic training
§ Dates back to 1930’s Woldemar Gerschler
§ Generally used in running events and swimming
§ Principles can be applied to any sport
§ Duration of the interval
§ Distance of interval
§ Number of reps and sets
§ Duration of rest or active recovery
§ Frequency
Exercise Testing and Prescription on Older Adults
· Aging Muscle and Strength
o After age 50
§ Muscle mass declines 1-2% each year
§ Muscular strength can decline 1.5% each year
o After age 60
§ Muscular strength can decrease up to 3% each year
o Age-related muscle loss
§ 25% in adults aged 65+
§ Increases to between 30-50% in adults 80+
· Functional Changes
o Strength
§ Grip
§ Upper-body
§ Lower-body
o Mobility and Functionality
§ Repeated chair stands
§ Timed up and go
§ 4-meter walk
§ 6-minute walk
§ Stair climb
o Age and Muscular Strength (see chart)
§ Rosenberg et.al. 1989, 1997
· First coined term “sarcopenia”
o Aging disease that effects changes in body comp and function
o Muscle mass and strength follow similar patterns over age
· Evans et. al. 1995
o Muscle mass, not muscle function, is the leading factor of age and gender related strength differences
§ Effects walking ability
§ Lower muscle strength related to falls
§ Reduced muscle mass decreases metabolic rate, can potentially result increases in fat deposition, decreased bone density, insulin sensitivity
§ Therefore, maintaining or increasing muscle mass will increase functional independence and decrease chronic diseases.
o Muscle quality
§ Several studies have emphasized the importance of muscle quality and its response to aging
· Specific Torque
· Specific force
§ Muscular strength is lost at a greater rate than lean mass with aging
o Assessment of Muscle Mass
§ MRI, CT scan, DEXA, BIA, Anthropometric Estimations (circ, skinfolds)
o Skeletal Muscle Index
§ Index of appendicular lean mass relative to height in meters squared
§ In attempt to normalize muscle to frame size
§ Gender differences remain because regardless of height, men tend to have more muscle mass that women
· Resistance Exercise Selection for older adults
o Core exercises
§ Recruit large muscle areas
§ Typically multi-joint (squat, pull-up)
§ Priority of training
o Assistance exercises
§ Typically recruit smaller muscle areas
§ Mostly single joint
§ “Prehab” type of exercises
· Exercise
o The aging process is accompanied with a myriad of potential conditions and diseases
§ Cancer, Type 2 diabetes, Osteoporosis, LBP, Arthritis, Depression, Muscle loss
o Aerobic and Resistance training produce many health related benefits
§ Decreased resting BP
§ Decreased risk of colon cancer
§ Less the severity and risk of type 2 diabetes
§ Maintain a strong skeletal system
§ Improve muscle loss
o Aerobic guidelines for Seniors
§ 2-5 times/week depending on training status and health history
§ Intensity prescription
· Typically 75% of max HR; however, age-predicted max can be very invalid
· Use RPE and talk test instead!!
§ Beware of medications: certain meds induce bradycardia, clients thereby have lower max HR
o Resistance Training and Seniors
§ 2-3 non-consecutive days
§ Begin in rep ranges of 8-12 reps
§ Address all major muscle groups, in a movement fashion (push/pull)
§ Beginning balance exercises
§ After a sufficient training time has taken place, power exercises (like med ball throws) may be important
§ Require a cool down after every exercise session!!!
Exercise in Chronic Disease and disability
· AIDS
o Progressive disease against the immune system
o Human Immunodeficiency Virus
§ Etiologic agent responsible for AIDS
§ 1997-2000
· 300% increase
· In 2000, 5.3 million new, recorded cases
§ No cure or vaccine for HIV
o HIV disease occurs from selective infection
§ CD4 cells decrease all immune function
· Results in immunosuppression
§ Increased infections
§ Decreased food consumption
§ Decreased lean body mass
§ Advanced body tissue wasting
§ Death
o Stages
§ Stage 1 – Asymptomatic HIV seropositive
§ Stage 2 – Early symptomatic HIV
§ Stage 3 – AIDS
o Challenges associated with AIDS
§ Fatigue****
§ Chronic diarrhea
§ Anemia
§ Muscle wasting
§ Pneumocystis pneumonia
§ Acute change in medical status = contraindication to exercise
o Exercise and AIDS
§ Aerobic
· Mode
o Cycling
o Treadmill
o Nu-Step
· Prescription
o Frequency: 3-5 x/week
o Duration: 20-60 min/session
o Intensity: 50-60% VO2 peak or 60-75% HR
§ Strength Training
· Mode
o Weight machines/free weights
· Prescription
o Perform on non-aerobic days
§ Flexibility
· Stretching/Yoga
· Massage therapy
· Goals:
o Increase ROM
o Increase neuromuscular excitability
o Decrease joint soreness and risk of injury
o Special Considerations
§ Strict universal precautions
· CDC/OSHA
§ Body comp analysis
§ Unknown effects of exercise in stage 3
§ Intense exercise and prolonged exercise
· Acute immune function depression
§ Medications
· Tachycardia, hypertension, anemia
§ Depression
§ Modify exercise based on patient response
· Spinal Cord Injury (SCI)
o Challenges Associated with SCI
§ Skin
§ Bones – due to non wt bearing
§ Trunk stabilization
§ Handgrip or foot placement – for good body posture
§ Bladder
§ Bowels
§ Hypotension
· 80/50 mmHg
§ Hypertension
· Paraplegia above T6
· Tetraplegia
§ Limited forced expiration
§ Thermoregulation
o VO2 Peak and SCI
§ Decrease of 1-26% depending on type and duration of w/c use
§ Exercise capacity
· Upright vs. supine
§ Exercise training improvements
· 10-20% improvement in VO2 Peak
· Central CV adaptations unknown
§ Arm exercise and VO2
· Values are half of leg exercise
§ Sympathetic NS involvement
§ Tetraplegia
· Values ½ to 1/3 lower than those with paraplegia
o Exercise and SCI
§ Aerobic
· Duration: 20-60 min/session
· Frequency: 3-5 days/week
· Intensity: 50-80% VO2 peak
· Mode
§ Muscle strengthening
· Frequency: 2-4 days/weeks
· Intensity: 2-3 sets of 8-12 reps
· Mode: weight machines, dumbbells, wrist weights
§ Goals
· Increase active muscle mass and strength
· Maximize overall strength for functional independence
· Improve efficiency of manual w/c propulsion
o Special Considerations
§ Depression
§ Cognitive Impairment or learning disability
§ Small but progressive improvements in fitness
· <5% per week
§ Supervision for BP
§ Environment
§ Abdominal bracing, TED hose or compression garments
· Diabetes
o Chronic metabolic disease
§ Absolute or relative deficiency of insulin
· Hyperglycemia
· Blood glucose level higher than 120 mg/dL
· Measure glycosulated hemoglobin (HbA1c)
o At risk for microvascular complications
§ Retinopathy
§ Nephropathy
§ Neuropathy
· Peripheral and autonomic
· Diabetic Neuropathy and Exercise
o In KS
§ 50.1% of adults with diabetes had at least 1 day of poor physical health in the last month
§ 28.4% of adults with diabetes had at least 1 day of poor mental health in the last month
o Potential benefits of exercise
§ Glucose control
· Enhance glucose uptake/insulin sensitivity
· Decrease glycosolated hemoglobin
§ Improve lipid profiles
§ Reduce BP
§ Weight loss
§ Increased strength
§ Improved well-being
o Exercise Rx Guidelines
§ Aerobic
· >150 min/week (3-4 daya/week at 20-60min)
o Intensity 50-70% max HR
· > 1000kcal/week (>2000 for weight loss)
§ Resistance exercise 3x/week
§ Monitor glucose before and after ex
· Insulin or hypoglycemic agents
· No exercise if glucose >205 or <70
o Guidelines for complications
§ Retinopathy (PDR) – avoid strenuous exercise, monitor BP
§ Peripheral neuropathy
· Loss of protective sensation leads to injury, Charcot joints = avoid weight bearing
§ Autonomic neuropathy = cardiac monitoring
§ Nephropathy = no restriction
· Chronic Kidney Disease (CKD)
o Overview
§ Permanent loss of kidney function
· Physical injury
· Disease
§ 20 million US adults had CKD
· ~20 million at risk
§ How is CKD diagnosed
· Markers of damage in blood, urine, imaging
· Glomerular filtration rate (GFR)
o <60 ml/min per 1.73 m2 for more than 3 months
§ Loss of kidney function
· Severe reduction in clearance of necessary waste products from blood
§ Diagnosis of end-stage renal disease (ESRD)
· Renal replacement therapy is required
· Results in severe metabolic abnormalities
o All physiologic systems will be affected
· Life threatening condition
· Greater than 45% of people with ESRD have diabetes, inactive and possess low functional capacity
o Challenges associated with CKD
§ Metabolic acidosis
§ Hypertension
§ Left ventricular hypertrophy
§ Anemia
§ Secondary hyperthyroidism
§ Peripheral neuropathy
§ Muscle weakness
§ Autonomic dysfunction
§ Elevated triglycerides and decreased HDLs
§ CHF
· Prior to dialysis
§ Accelerated atherosclerosis
§ Pericardial effusion (inadequate dialysis and uremia)
§ Abnormal EKG (disrhythmias)
· Electrolyte or structural changes
§ Cardiomegaly (fluid or pressure overload)
§ Renal osteodystrophy (hyperparathyroidism)
§ Persistent anemia (iron deficiency)
§ Peritonitis (catheter infection)
o Management of CKD
§ Most common form of maintenance therapy
· Hemodialysis (via arteriovenous fistula)
· Peritoneal dialysis (peritoneal catheter)
· Renal transplantation
· Medications
o HTN (anti-hypertensive meds)
o Anemia (EPO)
o Hyperparathyroidism
o CKD and Response to exercise
§ Low exercise tolerance
§ Blunted HR
§ Excessive BP increase
§ Termination of exercise = leg fatigue
§ ADL’s can be challenging to complete
· Improve tolerance
· Low cardiac output due to blunted HR response
· Reduced oxygen carrying capacity – anemia
· Extraction of oxygen below normal
o Muscle changes (structural, functional)
· Weakness
§ Effects of Exercise training
· Level of tolerance is unclear
· Changes in VO2 peak
o Driven by muscle efficiency/O2 extraction vs. Cardiac output
o Increase VO2 peak (~20-25%)
· Improved BP control
· Improved lipids
· Psychological benefits
· Resistance and aerobic exercise beneficial
o Skeletal Mm dysfunction
o Exercise Rx
§ Aerobic
· Mode: cycling, treadmill, use large muscle groups
· Frequency: 4-7 x/week
· Duration: 15-20 and progress to 60 min/session
· Intensity: 40-80% HR or as tolerated
§ Strength
· Mode: weight machines, free weights, isokinetic machines
· Avoid heavy weight
· Focus on low-weight – high reps
· Perform on non-aerobic days
§ Flexibility
o Special considerations
§ After dialysis tx, most don’t tolerate exercise or therapy
§ Be aware of arteriovenous fistula and IV access lines
§ Spontaneous avulsion fractures may occur in patients with long standing renal bone disease
· Dialysis > 5 years
§ 30% of dialysis pts have diabetes
§ Fatigue
§ Gradual progression of exercises
§ Pt set-backs do occur due to medical conditions; adjust POC
§ Exercise during hemodialysis if possible, or coordinate with dialysis staff
Exercise and Alzheimer’s Disease
· Alzheimer’s Disease (AD)
o Most common cause of dementia (50-80%)
o Marked by early memory impairment, executive dysfunction
o Facts
§ 5.3 million American’s had AD in ‘09
§ One in eight (13%) over 65 have AD
§ Every 71 sec someone develops AD
§ $148 billion in direct and indirect costs to Medicare, Medicaid, and business
o Early cognitive changes in AD
§ Memory loss
· Forgetfulness
o Conversations, appointments, meds, names
· Repetitions of questions, statements
· Misplacing Items
§ Executive Dysfunction
· Managing household
· Driving
· Meal Prep
· Operating appliances
o Non-Cognitive changes
§ Bone mineral loss
§ Lean mass loss
§ Sleep disturbances
§ Behavioral disturbances
· Agitation, Depression, apathy, delusions
· Presentation of Function
o CDR 1 – Mild dementia – MMSE 24
§ Discusses current events
§ Makes own snacks
§ Uses appliances
§ Reads
§ Dresses, bathes independently
§ Uses telephone
§ Travels outside of home
o CDR 2 – Moderate dementia
§ Spontaneous conversation has decreased
§ Might be clearing the table and disposing of litter
§ May be able to find belongings
§ No longer using appliances
§ No longer reads
§ Requires repeated cuing for dressing and bathing
§ May use telephone
§ Supervised outside of home
· Prevention Evidence
o Moderate exercise in mid- and later life was associated with lower risk for mild cognitive impairment in 1200 older adults
o Compared with no exercise, PA was associated with lower risk of cognitive impairment, AD, and dementia of any type in 4600 older adults
o Exercise 3x per week was associated with delayed onset of dementia
Exercise and Pediatrics
· Cardiovascular Responses to Exercise
o Cardiac output for healthy children increases 3-4 times above resting levels
§ Most of the increase is due to HR, only about 20-25% is due to stroke volume
o Children have markedly lower SV than adults at all levels of exercise, compensate by having higher HRs
o Boys: HR is lower and SV slightly higher
o No gender differences in Q or in arterial-venous O2 difference