AEXS 360 - Benefits & Risks Associated with Physical Activity (CH1)

Physical Activity

any bodily movement produced by the contraction of skeletal muscles that results in a substantial increase in caloric requirements over resting energy expenditure (>1 MET, >3.5 mL/kg/min VO2)

exercise

type of PA consisting of planned structured, and repetitive bodily movement done to improve and/or maintain 1 or more component(s) of physical fitness

physical fitness

set of attributes/characteristic individuals have or achieve that relate to their ability to perform PA and activities of daily living

health related components of physical fitness

cardiorespiratory endurance, body composition, muscular strength, muscular endurance, flexibility

cardiorespiratory endurance

ability of the circulatory and respiratory system to supply oxygen during sustained PA

body composition

relative amounts of muscle, fat, bone, and other vital parts of the body

muscular strength

ability of muscle to exert force

muscular endurance

ability of a muscle to continue performing without fatigue

flexibility

range of motion available at a joint

skill related components of physical fitness

agility, coordination, balance, power, reaction time, speed

agility

ability to change body position in space with speed and accuracy

coordination

ability to use senses (sight and hearing) together with body parts in performing tasks smoothly accurately

balance

maintenance of equilibrium while stationary or moving

power

ability or rate of performing work

reaction time

time elapsed between stimulation and the start of the reaction to it

speed

ability to perform a movement within a short period of time

METs

metabolic equivalents - represents amount of energy you are expending compared to rest

1 MET

3.5 mL/kg/min VO2

Light PA

1.6-2.9 METs

Examples of light PA

walking, making the bed/dishes/ironing, darts, playing musical instruments

Moderate PA

3.0-5.9 METs

Examples of moderate PA

walking 3.0 mph, heavy washing windows, car, clean a garage, carpentry, mowing lawn, badminton, golf, sailing, table tennis, tennis doubles

Vigorous PA

greater than or equal to 6.0 METS

examples of vigorous PA

walking at a very brisk pace (4.5 mph), walking/hiking at moderate pace and grade with no or a light pack, jogging at 5mph on a flat hard surface, shoveling sand, carrying heavy loads, heavy farming, casual soccer, skiing cross country, tennis singles, competitive volleyball

The difference between an older individual and a younger one performing at the same MET value

the older individual will work at a greater relative percentage of maximal oxygen consumption (VO2 MAX) than a younger individual due to age related declines in cardiorespiratory fitness.

what did the ACSM, CDC, US Surgeon General, and NIH do in the mid 1990s

they issued landmark publications on PA and health

- they clarified the amount and intensity of PA needed to improve health, lower susceptibility to disease (morbidity), and decrease premature mortality

what relationship was documented by these associations

a positive dose-response relationship between PA and health, meaning the more PA you do the better.

- some activity is better than none

- more activity (up to a point), and greater than less activity

recommendation for moderate intensity aerobic PA for 18-65 yo before 2018

30 mins 5x/wk

- can be completed in bouts, each lasting 10 or more minutes to add up to the full 30

recommendation for vigorous intensity aerobic PA for 18-65 yo before 2018

20 mins 3x/wk

how often should adults perform activities that maintain or increase their strength and endurance

at least 2x a week

what will exceeding minimum recommended amounts of PA do for individuals (longer duration and/or greater intensity)

increase fitness, decrease risk for chronic diseases/disabilities, and/or prevent unhealthy weight gain

data revelaed in 2018 about the advantages of PA

1. sedentary individuals can obtain health benefits from any intensity of PA (light/moderate/vigorous)

2. health benefits can occur from a single bout of moderate-vigorous PA (MVPA)

3. any bout of MVPA, regardless of duration, can be included when quantifying daily or weekly volumes of PA intended to be counted toward meeting recommendations

in 2018, what change happened to the guidelines

there was the elimination of the requirement that aerobic activities must occur in bouts of at least 10 minutes in duration to elicit significant health benefits.

- now it is acknowledged that PA in any amount of time bout (less than 10 minutes or more than 10), is considered beneficial

recommended amount of moderate intensity aerobic PA

150-300 min/wk

- PA > 300 mins/week of moderate intensity PA is associated with extra health benefits

recommended amount of vigorous intensity aerobic PA

75-150 min/week

recommended amount of muscle strengthening activities of moderate or greater intensity that involve all major muscle groups after 2018

greater than or equal to 2x/wk

estimated dose-response curve for atherosclerotic cvd for physical activity and fitness

increase percentage of guidelines completed decreases relative risk for atherosclerotic cvd

evidence classification: strong

consistent findings across a moderate number of studies

evidence classification: moderate

some inconsistent findings across a moderate numberr of studies

evidence classification: limited

inconsistent findings across few studies

evidence classification: insufficient evidence

inadequate, too few, or no studies to assess strength of evidence

evidence classification: not assignable

evidence inadequate or too disparate to generate a meaningful connection

variables that have a strong strength of evidence related to increased amounts of PA

all-cause mortality, cardiorespiratory, metabolic health, & weight loss

muscular health

breast and colon health

variables that have a moderate strength of evidence related to increased amounts of PA

Weight maintenance following weight loss & abdominal obesity

bone health, functional health,

endometrial and bladder health

variables that have a limited strength of evidence related to increased amounts of PA

Weight gain prevention

4 leading contributors o premature mortality

physical inactivity, tobacco use, alcohol abuse, poor diet/obesity

percentage of adults physically inactive globally

31.1 percent

percentage of adults that meet aerobic activity guidelines

50.9 percent

percentage of adults that meet muscle strengthening guidelines

30.4%

percentage of adults that meet aerobic activity and muscle strengthening guidelines

20.5%

sedentary behavior

any waking behavior characterized by energy expenditure less than or equal to 1.5 METS while in a sitting, reclining, or laying position

self reported sitting time

5.5-7.1 hours/day

PA effect on: premature mortality

increase life length

PA effect on: CVD/CAD

less heart disease and clogged arteries

PA effect on: hypertension

lower BP

PA effect on: stroke

reduced risk of blood clots or brain bleeds

PA effect on: osteoporosis

stronger bones

PA effect on: type 2 diabetes

better insulin sensitivity

PA effect on: metabolic syndrome

lower waist circumference, better lipids, better glucose

PA effect on: obesity

helps prevents weight gain

PA effect on: certain cancers

especially breast and colon

PA effect on: depression

improved mood and reduced symptoms

PA effect on: functional health

better ability to perform daily tasks

PA effect on: falls

improved balance and strength

PA effect on: cognitive function

better memory, attention, and brain health

Benefits of Regular PA/Exercise on Cardiovascular & Respiratory Function

increase:

- maximal oxygen uptake (VO2 MAX) from both central and peripheral adaptations

- skeletal muscle capillary density = more surface area for O2 exchange

- exercise threshold for blood lactate accumulation (fast glycolysis)

- exercise threshold for onset of disease signs or symptoms (angina pectoris = chest pain, ischemic ST segment depression, and claudication)

decrease:

- minute ventilation at a given absolute submax intensity (how much airflow goes in/out of your body)

- myocardial oxygen cost for a given absolute submax intensity

- heart rate and BP at a given submax intensity

Benefits of Regular PA/Exercise on decreasing Cardiovascular Disease Risk Factors

↓ resting systolic/diastolic blood pressure

↓ serum triglycerides

↓ total body fat and intra-abdominal fat

↓ insulin needs 🡪 ↑ glucose tolerance

↓ blood platelet adhesiveness and aggregation

↓ inflammation

↑ serum high-density lipoprotein cholesterol

Benefits of Regular PA/Exercise on decreasingwhat Morbidity & Mortality

decreased premature mortality, CAD, CVD, hypertension, stroke, T2DM, metabolic syndrome, osteoporotic fractures, cancers (bladder, breast, colon, endometrium, lung), gallbladder disease.

primary prevention

prevent the first occurrence of disease

secodnary prevention

interventions after a cardiac event to prevent another

other benefits of regular PA/exercise

- ↓ anxiety and depression

- ↓ risk of falls and injuries from falls in older individuals

- ↑ cognitive function

- ↑ physical function and independent living in older individuals

- ↑ feelings of well-being and quality of life (QOL)

- ↑ sleep quality and efficiency

- ↑ performance of work, recreational, and sport activities

- Prevention or mitigation of functional limitations in older adults

- Effective therapy for many chronic diseases in older adults

muscular fitness

the functional parameters of strength, endurance, and power

what are higher strength levels associated with?

- Significantly better cardiometabolic risk factor profile

- ↓ risk of all-cause mortality

- ↓ CVD events

- ↓ risk of developing physical function limitations

- ↓ risk for nonfatal disease

what PA/exercise is the one type to improve bone health

resistance training or plyometrics

what are are some risks of exercise

musculoskeletal injury, sudden cardiac death, and acute myocardial infarction

(these often happen after doing vigorous exercise after being sedentary)

when is risk higher for MSI

in activities with physical contact such as football, or wrestling

how many Americans had medical attention for sport related MSI in 2014

greater than 6.3 million

rates of MSI for 12-17 yo and 18-44 yo

12-17 = 83 per 1000 population

18-44 = 22 per 1000 population

(higher for younger pop bc they are learning how to lift properly)

most common anatomical sit for MSI

lower extremities; higher rates in knees, then foot, and then ankle

most common cause of sudden cardiac death among young individuals

congenital and hereditary cardiovascular abnormalities

annual risk of exercisw ralted death in young competitive US athletes in 1980-2011

1 per 62000 men

1 per 523000 women

death rates also appear higher in african american male athletes and basketball players specifically

What factors influence the risk of exercise‑related cardiovascular events?

Presence of unknown CVD, exercise intensity, age, and physical activity level.

According to the Physicians' Health Study, how often does sudden cardiac death (SCD) occur in men during vigorous exercise?

about once every 1.5 million episodes of vigorous physical exertion.

According to the Nurses' Health Study, how often does SCD occur in women during moderate‑to‑vigorous exercise?

About once every 36.5 million hours of moderate‑to‑vigorous exertion.

What did the Onset Study show about AMI (acute myocardial infarction) risk during or immediately after vigorous exercise?

AMI risk is 50× higher in habitually sedentary individuals compared to those who exercise vigorously for 1 hour more than 5 days/week.

Who has the highest risk of exercise‑related AMI?

habitually sedentary individuals performing sudden vigorous exercise.

What reduces the risk of AMI during vigorous exercise?

Regular vigorous exercise (≥1 hour sessions, >5 days/week).

Who has the highest risk of cardiovascular events during exercise?

Individuals with coronary artery disease (CAD).

How does facility capability affect mortality during cardiac rehab?

mortality is 6× higher in facilities without the ability to successfully manage cardiac arrest.

Do home‑based cardiac rehab programs increase cardiovascular complications compared to center‑based programs?

No — reviews show no increase in cardiovascular complications.

Why are CAD patients at the highest risk during exercise?

Because they already have compromised coronary arteries, making them more vulnerable to ischemia or arrhythmias during exertion.

Who should undergo preparticipation screening by qualified professionals?

High school and college athletes.

What certifications should individuals involved in exercise settings have?

AED, CPR, and ideally advanced cardiac life support

What are cardiac prodromal symptoms?

early warning signs of cardiac problems (e.g., chest discomfort, unusual fatigue, shortness of breath).

What should facilities ensure regarding cardiac emergencies?

Staff are trained, an emergency plan is in place, and appropriate resuscitation equipment is available.

How should physically active patients adjust their exercise programs?

Modify exercise based on changes in exercise capacity, habitual activity level, and environmental conditions.

How often should emergency procedures be reviewed and practiced?

At regular intervals to maintain readiness and reduce response time.