Body Composition and Health Flashcards
4 components of body composition:
- nutrient intake
- energy metabolism
- hormonal regulation of metabolism
- PA
BMI does not identify ….
low muscle mass
Body comp abnormalities in normal aging:
- skeletal muscle changes
- FM changes
- bone mass/density changes
____ ____ ___ is the second most variable component, within and between individuals after ___ ____.
- skeletal muscle mass
- fat mass
Skeletal muscle mass is relatively _____ within individuals during younger adulthood, after which mass begins to ____.
- stable
- decrease
Rate of muscle mass decrease is greater in ___ than ____.
- men
- women
Accelerated rate of muscle mass loss after ____ years.
65
FM changes with aging depends on ____.
race
Peak bone mass occurs around what age?
19-25
Fracture zone is at what age?
after 50
5 reasons why muscle declines with aging?
- age-related decrease in muscle area/volume
- age-related reduction in muscle protein synthesis rate
- loss of skeletal muscle fibre
- reduction in skeletal muscle fibre quality
- reduction in anabolic hormones
Age-related decrease in muscle area/volume starts in _____, and is associated with a reduction in ____ and ____ ____ ____.
- mid 40s
- strength
- muscle oxygen uptake
Why is there age-related reduction in muscle protein synthesis rate?
- progressive decrease in synthesis rate of myosin heavy chain
- decreased stimulation of muscle protein synthesis by AA (more AA needed to stimulate)
Loss of muscle fibres with aging thought to begin with….which causes the muscle fibre to ……
- the loss or impairment of motor neurons
- atrophy and eventually die
With aging, there is absolute reduction in type ___ muscle fibre area with relative preservation of type __ fibre.
- II
- I
In vitro studies of type I and type IIA muscle fibres found:
- lower maximal force compared to fibres from younger adults
- reduced shortening velocity compared to fibres from younger adults
- indicates that loss of muscle strength might not be only due to a reduction in the amount of muscle
Describe the reduction in anabolic hormones with aging:
- decrease GH, ILGF-1, estrogen/progesterone (effect on bone density), testosterone, and other androgens that are linked to a decrease in muscle mass and increase in BF
- insulin resistance
Sarcopenia:
loss of muscle mass and strength
Sarcopenia is ASM =
2 SD below the mean for young healthy adults
3 factors that may influence sarcopenia:
- age
- sex
- ethnicity
Sarcopenia spectrum:
- risk of falls
- metabolic disorders
- immune dysfunction
- mortality
Risk of falls can mean:
- potential fractures
- impaired ADL
- functional disabilities
Metabolic disorders include:
- insulin resistance
- arthritis
Immune dysfunction include:
- infection
- complications
- increased length of hospital stay
Obesity impact to health and wellness:
- glucose regulation
- depression
- CVD
- hypertension
Sarcopenia impact to health and wellness:
- mobility/frailty
- joint disorders
- strength/power
- functional capacity
Prevention/treatment of sarcopenia:
healthy diet and activity (resistance and aerobic exercise)
Aerobic activity effects:
- improves CV fitness and endurance capacity
- also helps with weight reduction thereby improving insulin sensitivity
- not enough to maintain muscle mass
Strength and power resistance training effects:
- reverses muscle weakness of sarcopenia
- shown to build muscle mass; increase strength (force production) and power (product of force and velocity)
- resistance training reverses functional decline in the elderly
Nutritional aspects in the treatment/prevention of sarcopenia:
- adequate nutrition
- protein intake (synthesis)
- energy intake (weight and muscle loss)
- vitamin D
- antioxidant nutrients
- polyunsaturated fatty acids
Aging is associated with a decline in ____, mainly ____ and _____.
- FFM
- skeletal muscle mass
- bone density
Aging is associated with _____ impairment and _____ and _____ changes.
- functional
- physiological
- behavioural
4 distinct body comp phenotypes in older adults are based on amount of ____ and ____ ____.
- muscle (ASMI)
- fat mass (FMI)
4 body comp phenotypes in older adults:
- normal
- sarcopenic
- obese
- sarcopenic obese
Normal phenotype:
- low adiposity
- high muscularity
- low prevalence
Sarcopenic phenotype:
- low adiposity
- low muscularity
- very low prevalence
Obese phenotype:
- high adiposity
- high muscularity
- high prevalence
Sarcopenic obese phenotype:
- high adiposity
- low muscularity
- moderate prevalence
Abnormalities in body composition (clinical setting):
- obesity
- sarcopenia
- osteoporosis
- cachexia
Abnormalities in body comp (clinical setting) can lead to:
- diabetes
- obesity
- aging
- HIV/AIDS
- spinal cord injury
- chronic obstructive pulmonary disease
- cancer
- rheumatoid arthritis
- sepsis
15% of obese patients with cancer are….
sarcopenic obese
Long term clinical implication: sarcopenia leads to ____% increase in overall _____ risks.
- 44%
- mortality
Short term clinical implication: abnormal body comp can lead to…
- physical disability
- frailty
- toxicity
- mortality
- readmission
- longer hospital stay
- complication
Comorbidities can lead to…
surgical complications (length of hospital stay, short-term mortality)
Alterations during chemotherapy: increased….
- oxidative stress
- systemic inflammation
- protein proteolysis
- tissue repair/cell turnover
Alterations during chemotherapy: decreased…
- PA
- food intake and nutrient absorption
Other alterations during chemotherapy:
- impact on body SA dosing
- altered pharmacokinetics
- increased dose limiting toxicity
- decreased treatment efficacy
Dose limiting toxicities:
- delays
- reductions
- discontinuation
- hospitalization
- death
Patients with lower ____ ____ are more likely to experience dose limiting toxicities.
lower lean mass
CT imaging provides _____ and _____.
- specificity
- precision
