Metabolism 2 Flashcards
what fraction of the population is obese or overweight? and what % are sedentary regularly
2/3, 50-70%
2 best things for weight loss
exercise and caloric restriction (30-60%)
a decrease of 30-60% ad libitum feeding without malnutrition
caloric restriction
PA recommendations to prevent weight gain
150-250min/wk equally 1200-2000kcal/wk
PA recommendations for weight loss
- less than 150 min/wk for minimal
- more than 150min/wk for moderate loss (2-3kg)
- more than 225-420 min/wk for high loss (5-7.5kg)
what type of exercise must be done for weight loss?
aerobic!! RT does not work but can reduce sarcopenia (loss of muscle mass)
- weight loss should not exceed how many pounds week?
- and caloric deficit should not exceed ?
- and daily caloric intake should be a minimum of?
2 lb/wk
1000kcal/day
1200kcal/day
vigorous caloric restriction can result in? (4)
- osteoporosis
- functional disability
- infertility
- amenorrhea
in primates, benefits of caloric restriction reduced risk of?
and exercise reduced risk of all these plus?
- diabetes (reduced abdominal adiposity)
- cardiovascular diseases
- cancers (insulin sensitivity)
- osteoporosis (exercise)
most notable health benefits of exercise over caloric restriction
- aerobic capacity
- muscle mass and muscle strength (reduced sarcopenia)
- improved bone health
exercise reduces sarcopenia, there is evidence that there are changes in ? (in the muscle)
- mitochondria
- protein synthesis rates
resveratrol (a compound found in grape skin) induces similar changes in gene expression as ? what areas?
–> effects may be enhanced by?
caloric restriction
- liver
- skeletal muscle
- heart
- neocortex
- adipose
- -> exercise
3 mimetics to caloric restriction
- resveratrol
- rapamycin
- metaformin
rapamycin effects regulation of various metabolic processes including (3)
–> what is rapamycin?
- nutrient and stress sensing
- protein synthesis
- cell survival
- -> antibiotic that comes from bacteria, used as a pharmacological intervention
? may be used as an immunosuppressant for treatment of various pathologies and in extending lifespan but also may have deleterious effects on ‘healthy’ individuals
rapamycin
metformin is widely used for?
- it reduces insulin sensitivity by 10-30% by: (3)
- diabetes
1. decreasing glucose production in the liver
2. increasing insulin dependent glucose uptake in peripheral tissues
3. promoting the usage of lipids
what happens to metabolism during a caloric deficit
adaptive thermogenisis (metabolism adjust, new set point for weight)
3 models of adaptive thermogenesis
- mechanical model
- threshold model
- spring load model
the main signal that adaptive thermogenesis suggest is?
a signal from adipose tissue regulates EE asymmetrically
–> the signal is the adipocyte-derived hormone
LEPTIN
a response to reduction in? preserves a “buffer” of energy stores critical to survival and reproductive function
fat mass
? repletion after reduced weight maintenance restores ? nervous system but not? nervous system tone or thyroid stimulating hormone levels to pre weight loss levels
leptin
sympathetic
not parasympathetic
ppl who were once obese and lost weight will have to do what compared to ppl who were never obese?
eat less and exercise more
3 key features of circadian rhythms
- an input pathways that receives for environmental factors
- a central oscillator that keeps circadian time and generates rhythm
- out put pathways through which rhythms conveyed and control various metabolic physiological and behavioural processes
the central clock is located where?
suprachiasmatic nucleus in the hypothalamus
