Exam 4 The Final Flashcards
Stretch- shortening cycles (SSC)
a Model that explains the energy-storing capabilities of the series elastic component and stimulation of the stretch reflex that facilitate a maximal increase in muscle recruitment over a minimal amount of time
Series elastic component (SEC)
elastic structures in series with the contractile component that can store energy like a spring after being forcibly stretched
SSC Stages
phase 1 - eccentric
phase 2- amortization
phase 3- concentric
Phase 1 - eccentric
stretch of the agonist muscle
- elastic energy is stored
- muscle spindles are stimulated
- signal is sent to spinal cord
phase 2- amortization
pause between phases 1 and 3
- nerves synapse (meet) in spinal cord
- signal is sent to stretched muscles
phase 3- concentric
shortening of agonist muscle fiber
- elastic energy is released from the SEC
- stretched muscle is stimulated by nerve
Series elastic component (SEC)
primarily involves the tendon but also series with the contractile component that can store energy like a spring after being forcibly stretched
plyometric exercise
a quick, powerful movement preceded by a pre-stretch (countermovement ) and involving the stretch-shortening cycle (SSC)
Purpose of plyometric exercise
to used the stretch reflex and natural elasti components of muscle and tendon to increase the power of subsequent movements
Speed:
ability to achieve high velocity
To development involves several componets
-exploitation of SSC
-development of f via ↑ muscle f production
-technique
-stride frequency and stride length
Plyometric exercise
exploits 2 components of the stretch - shortening cycle (SSC)
1 mechanical
2 neurophsiological
mechanical
Plyometric exercise
- as the SEC lengthens, elastic energy is stored
- if a concentric muscle action is performed immediately after the eccentric action, the stored energy is released and contributes to force production
- if the transition phase is too long, the stored energy is lost as heat
Neurophysiological
Plyometric exercise
- involves potentiality of the concentric muscle action by used of the stretch reflex
- muscle spindles sensitive to rate and magnitude of stretch
- a quick stretch of high magnitude results in a reflexive muscle action
- if the concentric action does not immediate follow the stretch, the potentiating ability is negated
What is it used for
Plyometric exercise
- to develop explosiveness
- starting power
- power (perhaps also joint stiffness)
- high-magnitude
- short-duration eccentric loading
what to consider
Plyometric exercise
This are all really important to considere
- age
- experience
- current training level
- injury history
- physical testing results
- training goals
- both upper and lower body are involved
Injury
Plyometric exercise
- intensity, volume, frequency, recovery should be appropriate
- ideally, plyometric training should take place when individual is freshest and most rested
- general and specific warmup should take place prior to PE
- assessment of jumping and landing biomechanic
Injury number 2
Plyometric exercise
- balance, proprioception, speed, strenght
- landing surface should be nonslip and posses shock- absorbing properties but not so much that the amortization phase becomes significantly lengthened
- shoes should have good ankle and arch support, good lateral stability , and a wide, nonslip sole
- do the goals of the individual warrant plyometric training
- some jobs and sports
Speed-strength
Speed Training
application of maximum force at high velocitie
Speed-endurance
speed training
ability to maintain running speed over an extended duration ( usually > 6 sec)
speed training
speed is ultimately dependent on energy, muscle force, form/ technique, stride frequency, and stride length
Technique
speed training
this is significant effect on speed expression
-maximizing sprinting apeed depends on a combination of optimal body posture, leg action, arm action
body weight
speed training
flat grade sprinting (often interval), form drills
sprint-assisted training
Speed training
- downgrade sprinting (3-7 dergges), hight speed towing, high speed treadmill
- should not ↑ speed by more than 10% of the indiidual max speed
resisted spriniting
Speed training
- upgrade sprinting, sled pulling (pushing), elastic tubing, parachute
- too much external resistance will become counterproductive to speed development
Volume
Quality of effort is crucial
speed training
volume does not need to be particularly high if quality of effort is high
- high bolume with low quality may be essentially useless
- -conditioning, work capacity and mental toughness training have different goals
- –be sure to know what the goal of the training is
Spped
Quality of effort is crucial
speed training
-speed training should take place when individual is freshest and most rested
-does not always happen that way for athletes whose sport is not running
Example on on the handout
high levels Strenght/power
will only help so much in the absence of optimal technique
- some will naturally have good technique, most will probably require some coaching
high speed running
requires high power production capabilities
- person can be strong an not powerful BUT a person ca NOT be powerful without also being strong
- –optimal development of sprinting speed probably requires a combination of running training and strength training and power training
straight line and Lateral movement
lateral movement involves ability at accelerate, decelerate, change direction, accelerate
- -in sports this occurs at high speeds and under high forces (agility training )
- *speed training and plyometric training in the same session (or even the same day) might be problematic
Plyometrics
Joes PP
yuri verkhoshanky in russia in ealry 1960
- shock method
- father of plyometrics
Plyometric
.
pilometric
.
power metric
.
Injury considerations
Joes PP
- injury risk is elevated with these types of exerise
- reaseach is less clear
- guideline exist for this such as you should be able to lift a certion amount first
- most are from overused injries or injury due to poor form (quanlity is better than qunaityt)
Who should preform plyometrics
Joes PP
- perform a need analysis
- -peeps who need to be explosive
- sports and jobs
“triain the way you play”
– old peopel can do this too
Benfit risk ratio NEEDS to be looked at
contrast load
Joes PP
-alternating sets of strenght with power
Strength
-load- 85% 1RM
Power
- load- 30-45% 1RM
- have to have light weight and fast to work
Plyometrics
Joes PP
the lower body is jumping type motions
- Upper body can be used too
- – more with explosive push ups
- this can really hurt the wrist and shoulders
- work with medican balls is the best
Esploiting the SSc
- the time btwn the concetric and eccentric need to be short
- long SSC- >250 ms
- short SSC
Post activation potentiation
Joes PP
.
Post activation potentiation part 2
Joes PP
- ↑ in throw height following tradtional heavy load barbell lift
- 3 sets of 3 reps of 80% 1 RM in bench press was performed first
- after 10 min of rest, throws were performed & by 38-40% this was a huge diff
muscle - tendon unit
Joes PP
→// elastic compenent (pec) -epimysium, perimysion, endomysion, sarcolmmal →series elastic component (sec) -tendon cross bridges, myoflimanet , →contractile component (cc) -actin, myosin, cross bridges
Contribution of SEC
Joes PP
-estimated that elastic energy may account for 20-30% of the diff btwn a countermovement & noncountermov. jump
Plyometrics part 3
Joes PP
- used to ↑ speed, power, quikness
- typically involved something (movement ) that invovles a release
- also called stretch - shortening cycle training
- exploitation of the ssc lead to ↑ force production during a con. phase.
Back ground
Musculoskeletal injuries
- risk of injury with any physical activity, sport, E
- range from (serious or minor)
identifying risk of injury
Back ground
Musculoskeletal injuries
1 personal/medical history
2 known association w/ certain activities
–lower back injuries in lifting
– tendinitis in repetitive movement
–shin splints in running
3 injury- prone people
4 idea of pre habilitation has gained much attention in recent years
spontaneous?
Back ground
Musculoskeletal injuries
some injuries appear to be spontaneous with no warning signs! but many have warning signs but you just dont recongnized them
common ingredients for MS injuries
Back ground
Musculoskeletal injuries
-bad techniqu (fatigue, inflexibility, miseducation) -excessive overload (stress-strain-failure relationship) -chronic overuse -ignoring warning signs
Freak injury
Back ground
Musculoskeletal injuries
usuall very rae and upreditable but can have catastrophic consequences
- the guy that was paralyed during a lift ( crossfit) video in class
Injury types ( acute )
1 strains
2 sprains
Strains
Injury types
1 tears/ ruptures avulsion involving muscle and bone
2 muscle tears graded by degree of damage
3 muscle tear can present with a significant contusion/ hematoma
muscle tears graded by a degree of damage
Strains
Injury types
1st- partial tear; strong but painful muscle activity
2nd- partial tear; weak and painful muscle activity
3rd- complete tear; very weak and painless muscle activity
Sprains
injury types
-ligaments trauma 1 blunt force or other trauma 2 intervertebral disc herniation 3 skeletal fracture 4 other --dislocation --subluxation
dislocation
complete displacement of joint surfaces
subluxation
partial displacement of joint surfaces
Injury types (chronic)
- overuse
- intervertebral disc bulging
overuse examples
injury types
tendon: tendiopathies
bone: skeletal microdamage- stress fractures
overuse ingredients
injury types
1 poor program design 2 suboptimal training surfaces 3 faulty biomechanices/ technique 4 insufficient motor control 5 ↓ flexibility 6 skeletal malignant
Intervertebral disc anatomy
injury types
nucleus pulposus- the middle portion
annulus fibrosis-the outer parr
commonly injured joints/ areas
1 strength training: knee, shoulder, low back , wrist, elbow, neck
2 endurance training: knee, foot, ankle, lower leg, hip
Management
1 acute injuries
2 chronic overuse injuries
3 professionals involved
acute injuries
management
1 know emergency response and 1st aid procedures
2 direct injured person to appropriate medical personnel
3 soft tissue injuries: rice, heat/cold application
chronic overuse injuries
management
1 avoid aggravating activity/ movement
2 analgesic and anti- inflammatory medication
–masks the symptoms often does not fix the problem
–underlying problem can get worse becuz body normal means of letting person know there isa problem have been impaired so the damage continues
professionals involved
management
1 athletic trainers 2 physical therapists 3orthopods 4 psychologist 5 nutritionists 6 other
Athletic trainers
professionals involved
management
usually involved in acute, on the field management in athletic settings
- may also be involved in rehabilitation
physical therapist
professionals involved
management
usually involved in rehabilitation setting
orthopods
professionals involved
management
can be involved in any aspect of injury management
- also responsible for advanced treatment (surgery, mediction)
psychologists
professionals involved
management professionals involved
management
can deal with recovery issues and other issues too)
nutritionists
professionals involved
management
proper nutrition can play a role in injury prevention and recovery
other
professionals involved
management
exercise physiologists , strength and conditioning coaches, personal trainers
Grip/ hand/ finger strength
-WHO CARES
exp ot pt strength coaches personal trainers *cant do anything 20 pounds per hand means that you cant do everyday activities
Grip Strength
- grip training can be a separate endeaver altogeher (separate from general ad sport - specific strength training)
- many forms of hand/grip/finger forearms
- often contested in specific grip related comptitions
Types of grip strength
1 supporting
2crushing
3 pinching
supporting
types of grip strength
ability to maintain a hold on something for a while- pullups, deadlift, shopping trips
Crushing
types of grip strength
grip btwn your finger and your palm the one you use for shaking hand and crumpling cans
Pinching
types of grip strength
grip btwn your finger and your thumb. this can be further sub categorized into individual finger and the thumbs grip
TA and medial tibial stress syndrome
- relationship
- cause
- prevetion
- treatment
- they dont know about them
Selecting stress methods
1 contrasting training 2 accoummodaing resistance 3 range of ROMtraining 4 isometric training 5eccentric training (negatives) 6 paued repetitions 7 oscillatory movements 8 vibration training 9 repetition schemes 10 real time tracking of movement 11 autoregulation
Contrasting Training
altering sets of strength with power
1 strenght exercises ( bench press)
–heavy loads(85+ 1rm)
2 power (vertical jump)
– light load (30-45% 1rm)
Contrasting Training EFFECTS
acute: post activation potentiation
chronic: power enhancement
accommodating resistance
1 varies through the ROM
– band, chain, weight release
2 works with strength curves
3 instability may confer addition independent effects
4 debated about amount of resistance that should be used
ROM training (PARTIAL ROM)
1 sticking point
– improve strenght at the wakest point in the ROM
2 very short ROM
– ↑ neuromuscular stress
ROM training (EXCESS ROM)
Typically used to strenghten a weak point at one end of the ROM
- deadlifting and standing on a board
- pressing with a camvered bar
Isometric training
1)Static hold at either end of the ROM Effects 1 neuromuscular 2core and stablizers 3 muscular
- holding a heavy load as you stand up ( more than you can lift)
2) pushing against an immovable object
Eccentric training (Negativies )
typically involved the lower phase using a resistance that exceeds that which can be overcome in the concentric portion (me doing a pull up backwards)
1 focus on going slow in the ecentric phase
2 concentric phase will need a partner or rerack
*shouldnt need to do this more than once
Paused repetitions
removes the added benefits of the stretch reflex
Eccentric training (Negativies ) EFFECTS
-neuromuscular
-muscular (DOMS)
1 often overdone and or perfored by individual not fit
2 risk: super increase may lead to injury
Oscillatory movements
the shake weight lol
quickly oscillating through a very short range of motion
Vibration training
- involved perfomring movement on vibrations platform
- thought to enhance neuromuscular factors
- can be easily over done
- can help with bone strenght
repetition schemes
cluster training
* taking a break btwn each rep (short break)
Real time tracking
tendo units
- relay information about speed of bar movement as an indicator of neuromuscar status and acutley guides training
- tyying to get optimal stress comparted with someones CNS system for the day
autoregulation
-attempts to determine an ind. state of readiness (CNS)
and plans the triangin around that state of mind
-afford training session some flexibility to accommaodate the body daily changes
Other trainging
- ischemic training – cutting off the blood flow than lifting
- cooling your whole body down then lifting
easy to over train the CNS
- symptoms not always obvious
- an amount of CNS stress that is too much for one person might be insufficient for another
many mysterious still exist regarding the CNS and how to optimally train it
- becareful what you read about working out not everyone is right on the internet
- not a lot fo quality research is being done becasue they are spending money on other thing like heart disease
Age definition
old: 65-74
very old: 75-84
oldest old: 85 and older
*also 50-65 is also older adults
65+ population
1900= 3 mil (4%) 2010= 40 mil (13%) 2040= 80 mil (20%)
functional/physical decline with age:
1 effects of aging result in gradual impairment
2 sudden decline often attributed to chronic disease
Effects of exercise (older )
1 slowing physiologic change of aging that impair E capacity
2 altering age related changes in body composition
3 promoting psychological and cognitive well- being
4 managing chronic disease
5 reducing the risk of physical disability
6 reducing the risk of physical disability
7 ↑ longevity
8 strengthening M, bond, CT (fx ↑, ↓ injury risk)
reported rates of regular physcial activity participation in older adults
- 65+ (22%)
- 85+ (11%)
Frequency
Older aerobic activity
-min 5 dpw for mod- intensity
-min 3 dpw for vigor- intensity
- combination of mod- vig intensity 3-5 dpw
TIME
-mod (30-60min/day)
-vig (20-30 min/day)
scale intensity (0-10) 5-6 mod and 7-8 vigor
Mode
Older aerobic activity
any modality that doesnt impose excessive orthopedic stress or other risk
- walking is common
- aquatic exercise or stationary cycle E may be advantageous for those with limited tolerance for weight bearing activity
Frequency
older Flexibility training activity
- at least 2 days per week
Intensity
older Flexibility training activity
moderate - intensity (5-6) on 0-10 scale ; go tot point of tightness/slight discomfort
Mode
older Flexibility training activity
any activities that maintain or increase flexibility using sustained stretches for each major muscle group
–static movement , not ballistic
Frequency
older muscle strengthening activity
- at least 2 days per week (noconsecutive day )
Intensity
older muscle strengthening activity
between moderate (5-6) and vigorous (7-8) on 0-10 scale
Mode
older muscle strengthening activity
progressive weight- training or program or weight bearing calisthenic
-(8-10) exercises involving major M Groups
- (10-15 repetitions each)
1 stair climbing
2 other strengthening E that used the major muscle groups
Frequency
Older Balance exercise activity
at least 2-3 days per week
Mode
Older Balance exercise activity
exercises that incorporate neuromuscular training
- balance, agility, and proprioceptive training
- progressively difficult postures (gradually reduce base of support )
- dynamic movements that perturb the the center of gravity
- stressing of postrual muscle groups
- reducing sensory input
- tai chi
- ** supervision is important
Bone fractures and prevention
hip fractures in particular are associated with increased disability and death
- Older adults have 5-8 fold increased risk for all cause mortality in first 3 months
- after 3 month to rishk of mortality decrease but do not get better
- men have more annual mortality after hip fractures
E and physical activity is crucial for bone health/strength
Bone fractures and prevention
- slowing rate of bone loss with aging
- reducing the risk of falls via benefits from ↑ muscle strenght and balance
Reduce the changed of sustaining a fracture by:
Bone fractures and prevention
1 ↑ bone strength
2 ↓ chances of falling
intensity and duration should be low at the beginning for those that are:
Special considerations older
1 highly deconditioned
2 functionally limited
3 suffereing from chronic conditions that affect their ability to perform physical tasks
Summary
older
- any movement is better than none
- priorite are
1 funciton: balance, flexibilty, strenght
2 disease: exercise as medicine
-medical screening and clearance is important
Purpose fo physcial activity in older adults
summary
1 disease prevention and management
2 function
attenuate decline in funtion associated with age and diseas
and maintain ability to carry out ADL
3 psychological well-being
socialization and management of depression
and self efficacy
types of ages
Biological age- puberity age
Chronological age- how odl
training age- how long have you been training
Age definitions of children
Children:
purpose of E and physical activity in children
aerobic fitness, muscle strenght, bone mineral density, motor performance skills, body composition, psycho social well-being will ↓ injury risk
disease risk modification
Problematic trends over the past couple decades children
o decreased physical activity
less exposure to physical education in the school setting
increased technology
“acceptance” of sedentary lifestyles and the accompanying decrease in fitness and
increase in body weight (i.e., fat)
decrease in sporting activity participation “just for the fun of it”
o poor dietary habits
increased availability
increased acceptance
o lack of role models as they specifically relate to a physically responsible lifestyle
Habits and lifestyles behaviors and first formed in childhood
o active and healthy children are more likely to continue those habits into adulthood
and vice versa
School is one place that ingraining a healthy lifestyle can be achieved fro many children
o problems
decrease in physical education opportunities
traditional model of physical education (i.e., sports-oriented)
– children are not minature adults (physcally, physiologically, emotionally, mentally, socially)
Aerobic fitness children
aerobic fitness
o relationship between physical activity and aerobic capacity not as clear as with adults
limitations in measurement capabilities
children may have an acceptable level of aerobic fitness that is independent of
physical activity
aerobic systems may not be as “trainable” in children compared to adults or the
intensity levels required to enhance aerobic capacity are higher than those of
adults
Blood pressure children
prehypertension = 90th percentile (for age and sex)
3.4% of children aged 3-18 years old
hypertension = 95th percentile (for age and sex)
3.6% of children aged 3-18 years old
-you use % ranges not the numbers
Weight children
o statistics
criteria (based on BMI)
at risk for obesity (i.e., overweight) = 85th percentile (for age and sex)
obese = 95th percentile (for age and sex)
U.S. [NHANES] data for 2011-2012 (published in JAMA on February 26, 2014)
children and adolescents (2-19 years old)
o 16.9% at or above 95th percentile
o 31.8% at or above 85th percentile
o risks associated with adolescent obesity
elevated
total cholesterol, LDL cholesterol, triglycerides, blood pressure
lowered
HDL cholesterol, fasting insulin
o atherosclerotic process begins in childhood but often is not manifest until adulthood
process may be accelerated due to the consequences of childhood obesity
Arteriosclerosis
any hardening (loss of elasticity) of the arteries
Atherosclerosis
hardening of arteries due to atheromatous plaque
Skeletal health children
o overweight and obesity may not be “protective” against osteoporosis as once thought
o recommendations
weight-bearing activities involving large muscle groups and higher-intensity
loading patterns are preferred (“natural” childhood activity patterns)
Psychological social and emotional healthy children
o relationship between physical activity and:
depression, anxiety, stress, self-esteem, self-concept, hostility, anger, and
intellectual function
Same pre testing procedures apply to children with some additions
o child’s assent (agreement) and parental consent (permission)
o give clear instructions and ensure child’s understanding of what is expected
physicla activity assessment children
o heart-rate monitors, activity monitors (pedometer, accelerometer), direct observation, selfreport
questionnaires
o still difficult to quantify
Aerobic capatiy and aerobic fitness children
o laboratory tests
maximal oxygen uptake
high VO2 max in children not always predictive of endurance performance
peak or maximal values?
different protocols than adults
EXP 3342 - April 29, 2016 3
o field tests
endurance tests (1, 1½, 2-mile run/walk; distance completed in a specified time)
pacing, attention, and motor skills are problems in children
step test
other (e.g., PACER)
o children may require extra instruction, support, and motivation during an exercise test
Body composition children
o body mass index (use norms for children)
o sum of skinfolds (be aware of different skinfold sites for children)
o other methods
girth measurements, hydrostatic weighing, bioelectrical impedance, dual-energy Xray
absorptiometry
be aware of differences in protocols and norms with children compared to adults
o issues
personal contact and privacy
child’s interpretation/perception of what is said to them (e.g., the word “fat”)
Flexibility children
o trunk flexion (sit-and-reach protocols)
o other tests specific to testing batteries (e.g., trunk extension, shoulder flexibility)
Muscular strength and endurance children
o body weight-dependent tests probably best option
tests that do not discriminate well between strength levels can be a problem
o use traditional strength testing protocols (i.e., free weights) with caution
one-repetition maximum testing generally not recommended
higher repetition testing better option for most
technique instruction is crucial
Anaerobic capacity children
o Wingate cycle test
o maximal jumping (vertical or horizontal)
o sprinting speed (e.g., 50-yd run)
influenced by experience and motor skills
(Aerobic)
ACSM: minimal amount of physical activity recommended for achieving the various components of
health-related fitness: Children
frequency: daily
intensity: moderate to vigorous
vigorous intensity exercise/physical activity at least 3 days per week
time/duration: ≥60 minutes per day of accumulated physical activity
type/mode: variety of activities that are enjoyable and developmentally appropriate
for the child or adolescent
examples: walking, active play/games, dance, sports, and muscle- and
bone-strengthening activities, work, transportation, recreation, physical
education, planned exercise
(resistance training- guidlines )
ACSM: minimal amount of physical activity recommended for achieving the various components of
health-related fitness: Children
≥3 days per week as part of 60min+ of daily exercise
resistance is generally lower (absolute and relative)
repetitions are higher (lower resistance; focus on technique development)
body weight exercises are a good mode
o sufficient resistance for many (too much or not enough for some)
consider playground equipment, climbing trees, tug-of-war, etc.
consider exercises/activities that develop motor skills and body awareness
(resistance training-supervision )
ACSM: minimal amount of physical activity recommended for achieving the various components of
health-related fitness: Children
teaching proper technique and constant monitoring to ensure proper
technique is being used at all times
children’s attention spans not high
competitiveness between children
children do not have the intelligence or common sense that adults have
(bone strengthen E )
ACSM: minimal amount of physical activity recommended for achieving the various components of
health-related fitness: Children
running, jumping, jumping rope, basketball, tennis, hopscotch, soccer, etc
Parents and children
o some are overbearing and force their children to train for sport purposes
o some are uneducated in the area of exercise/training (or the human body in general) and
some let their ego get in the way
“I know more than you” or “I was an athlete and this is how I did it”
“I read this or that in a magazine” or “I heard this from so-and-so”
o some are overprotective and think any exercise or training is dangerous
dangers and risks of youth strength training has probably been exaggerated over
the past 30 years (risks do exist though)
Body composition and children
o keep track of body composition but be aware that many things can change as a child goes
through maturation
o avoid a concentrated focus on “weight loss” or “fat”
but be mindful of the more extreme situations for which significant intervention is
needed even at a young age
o avoid testing procedures or language that might be psychologically damaging
children are often very emotionally vulnerable in ways that are not always obvious
Cardiovascular training and children
o standard adult prescriptive techniques may not be suitable for children
emphasize physical activity and movement as opposed to “exercise” and “training”
be cautious of focusing on specific durations, intensities, and modes of exercise
accumulation of moderate and intense physical activity is important
the natural physical activity patterns of children are intermittent in nature
(stop-and-go, stop-and-go), not long and sustained efforts
Extra stuff from children
advanced programming strategies may be required for young athletes (training age important)
encourage a variety of training modalities and try to make it fun for the child
avoid machines that are designed for adult body dimensions (child-sized machines exist)
Background and females
female participation in exercise, physical activity, and sport has increased dramatically in past
several decades due to:
o knowledge of health benefits of exercise and physical activity
o passage of Title IX legislation in 1972
reduced societal prejudices and obstacles for females to participate in sports
females generally respond to training and exercise in the same way males do but there are some
issues specifically related to females:
o reproductive function menstrual cycle pregnancy metabolic disturbances, thermoregulatory concerns, hypertension, fetal health o orthopedic issues o eating disorders
The female athlete triad
historically defined as:
o disordered eating
o amenorrhea
o osteoporosis
The female athlete triad
in 2007, ACSM updated their position stand and describes the triad as 3 interrelated spectrums:
o optimal energy availability to low energy availability (with or without eating disorders)
o eumenorrhea to amenorrhea
o optimal bone health to osteoporosis
The female athlete triad
low energy availability can lead to amenorrhea
o has been observed since the 1950s that intense training was associated with menstrual
cycle changes
The female athlete triad
cessation of menstrual cycle is associated with low bone mineral density
o reductions in bone mineral density at a young age may never be regained and may
increase the risk of osteoporotic fractures
The female athlete triad
many female athletes and coaches believe low body weight is necessary for success because:
o lower body weight = less body mass to “move”
o lower body weight = better body image
Low energy availability Females
unintentional negative energy balance
o can be difficult for athletes to consume enough calories to match their caloric expenditure
Low energy availability Females
intentional negative energy balance to achieve “ideal” body type
o excessive caloric expenditure (often through exercise or training)
o excessive caloric restriction
diet pills, laxatives, diuretics, fasting, vomiting
o eating disorders
Low energy availability Females
Eating disorders
anorexia nervosa
psychological disorder characterized by
o obsession with thinness
o intense fear of becoming obese
represents an absolute restriction of calories that results in an unhealthy
loss of bodyweight (at least 15% below ideal body weight)
o low to very low caloric consumption
o often accompanied by excessive caloric expenditure
Low energy availability Females
Eating disorders
bulimia nervosa
characterized by recurrent episodes of binge eating
o often followed by purging (e.g., self-induced vomiting, use of
laxatives, use of diuretics, fasting, exercise)
not always accompanied by a loss in bodyweight
Low energy availability Females
Eating disorders
eating disorder not otherwise specified (EDNOS)
disordered eating
Low energy availability Females
o potentially high-risk sports (i.e., high risk for developing an eating disorder)
dance, figure skating, gymnastics, distance running, cycling, cross-country skiing,
volleyball, swimming, diving, horse racing, martial arts, rowing
Menstrual disturbances
normal menstrual cycle is the result of a precise synchronization of hormonal events in the
hypothalamus, anterior pituitary gland, and ovaries
o a proposed mechanism of the menstrual disturbances associated with vigorous exercise
and/or low energy intake is an imbalance in the hypothalamic-pituitary-gonadal axis
Menstrual disturbances
types of menstrual disturbances
o delayed menarche: menstruation not started by age 16
o shortened luteal phase: duration less than normal 10-16 days
o anovulatory cycles: menstrual cycle without egg release
o oligomenorrhea: irregular or inconsistent menstrual cycles
o amenorrhea: complete cessation of menstrual cycle
types of amenorrhea
primary: absence of menstrual cycles by age 15 in previously
nonmenstruating girls, even when other normal postpubertal development
is present
secondary: menstrual bleeding has not occurred for at least three to six
consecutive menstrual cycles in women who have already had at one
previous menstruation
Menstrual disturbances
prevalence of amenorrhea
o general population: 2-5%
o women engaged in vigorous exercise training: 5-46%
o elite runners: 40%
o professional ballet dancers: 66%
Osteoporosis (diagnosis by DXA)
osteoporosis: BMD ≥2.5 standard deviations below average bone mass for a young sex- and racematched
reference population and/or the presence of a fragility fracture
osteopenia: BMD ≥1 but
Pregnancy
benefits associated with exercise during pregnancy
o improved cardiovascular function and better fitness level
o limited weight gain and body fat retention
o improved digestion and reduced constipation
o reduced back pain
o improved attitude and mental state
o easier labor or reduction in possible complications during labor
o reduced odds of cesarean delivery
o faster recovery
o reduced risk of pregnancy-induced hypertension and gestational diabetes
o beneficial effects on offspring?
Pregnancy Extra
women who have been sedentary before pregnancy or who have a medical condition should
receive clearance from their physician before beginning an exercise program
PARmed-X for Pregnancy should be used for the health screening of pregnant women before their
participation in exercise programs
maximal exercise testing should not be performed on pregnant women unless it is medically
necessary (in those cases a physician should be present)
Pregnancy Exercise prescription
o generally consistent with recommendations for the general adult population
o important to monitor and adjust exercise prescriptions according to the woman’s symptoms,
discomforts, and abilities during pregnancy
be aware of contraindications for exercising during pregnancy
Pregnancy Exercise prescription
recommendations
frequency: at least three (and preferably all) days of the week
intensity: moderate intensity
based on heart rate (might not be the best option):
o age 40: 125-140
based on rating of perceived exertion: RPE 12-14 (on scale of 6-20)
based on talk test: being able to maintain a conversation during activity
time/duration: at least 15 minutes per day gradually increasing to at least 30
minutes per day of accumulated moderate-intensity activity (total of 150 minutes
per week)
type/mode: dynamic, rhythmic physical activities that use the large muscle groups
such as walking and cycling
Pregnancy Exercise prescription
o special considerations for pregnant women and exercise
those who have been sedentary or have a medical condition should gradually
increase activity to meet the recommended levels
those who are morbidly obese and/or have gestational diabetes or hypertension
should consult their physician before beginning an exercise program
exercise prescription should be adjusted to their medical condition,
symptoms, and functional capacity
avoid contact sports and activities that may cause loss of balance and trauma
examples: soccer, basketball, ice hockey, horseback riding, vigorousintensity
racquet sports
exercise should be terminated if any of the following occur:
vaginal bleeding, dyspnea before exertion, dizziness, headache, nausea,
vomiting, chest pain, excessive palpitations, muscle weakness, calf pain
or swelling (of ankles, hands, or face), preterm labor, decreased fetal
movement, amniotic fluid leakage, sudden onset of abdominal or pelvic
pain, acute illness
Pregnancy Exercise prescription
o special considerations for pregnant women and exercise 2
avoid exercising in the supine position after the first trimester to ensure that
venous obstruction does not occur
avoid performing the Valsalva maneuver during exercise
avoid heat stress by exercising in a thermoneutral environment and maintaining
adequate hydration levels
increase caloric intake to meet the caloric costs of pregnancy and exercise
during pregnancy the metabolic demand increases by ~300 kcal/day
strength training is safe and should incorporate all major muscle groups with a
resistance that permits multiple repetitions to be performed to a point of moderate
fatigue (i.e., 12-15 repetitions)
isometric muscle actions and the Valsalva maneuver should be avoided
exercise in the supine position should be avoided after the first trimester
exercise in the postpartum period may begin as early as ~4-6 weeks after delivery
deconditioning typically occurs during the postpartum period
o physical activity levels should be gradually increased until
prepregnancy physical fitness levels are achieved
physical therapy for pelvic floor rehabilitation?
Pregnancy Exercise prescription
Other issues
female anabolic steroid use for athletic advantage and/or aesthetic reasons
ACL injury: females are at a 4-9 times greater risk of ACL injury than their male counterparts in the
same cutting and landing activities/sports
o theorized causes: anatomy, hormones, flexibility, joint laxity, neuromuscular factors,
sociocultural effects…..and others
sex differences in strength
o largest contributor = testosterone (male = 6-7mg/day; 40-60x greater than females)
o females have ~40-50% of the strength of males in upper body movements
o females have ~50-80% of the strength of males in lower body movements
o differences lessen when strength is expressed relative to muscle cross-sectional area
strength training in women (injury fears, self-efficacy, miseducation, intimidation, social norms, etc.)
