Environmental Physiology - Final Exam Flashcards
What are the stages of sleep?
Transition phase, light sleep, start of slow wave, slow wave, rapid eye movement (REM)
Slow wave sleep
Very restful (deep), BP, breathing rate and metabolism slow down, dreamless sleep.
REM Sleep
5-30 minutes long, irregular heart rate and breathing rate, active dreaming and body movements.
Biorhythms
Can last a few minutes to a few months. Immune function can suffer. Diurnal pattern (25 hours)
Examples of biorhythms
Kidney fxn, HR, BP, VE, Tcore, O2 consumption, CATs, reaction times, hand-eye coordination.
Circadian Rhythm
External cues: zeitgebers or synchronizers - Sun.
Internal cues: Are regulated by suprachiasmatic nucleus - neuroendocrine and thermoregulatory rhythms are controlled by SCN.
Enhances biological fxn and helps adjust to natural changes in environment.
Normal nightly requirement of sleep
7-hours
Sleep Deprivation
Long term - more than 45 hours
Short term - less than 45 hours
Partial SDEP - less than 7-24 hours
Physiological Responses
Tcore, Tskin and catecholemines all affected, cognitive function decreases
Performance effects
Larks - morning workouts
Owls - afternoon workouts
Jet Lag
Results when circadian rhythms are thrown out of sync.
Circadian rhythms shift 1 hr/day
West coast - later 1 hr
East Coast - earlier 1 hr
It becomes increasingly difficult to adjust when an individual crosses over….
5+ time zones
Athletes require how man days to recover from international travel?
2-10 days
Recommendations for counteracting jet lag
Arrive to destination early (14 days minimum)
Exercise upon arrival
More alcohol
Alter diet
Sleep loss, health, and performance
Missing 4-hours reduces immune function by 28%
Motor vehicle fatalities are commonly caused by fatigue - 20% have fallen asleep at the wheel
18 million Americans suffer from sleep apnea
60 million Americans suffer from insomnia
Who responds to SDEP better?
Larks, anxious people and old people
Sleep and Physical Fitness
17-19 hours of SDEP = BAC of 0.05%
Physical performance impaired
Sleep and Weight Control
Increased ghrelin, decreased leptin, satiety is altered, hungrier with SDEP
SDEP compromises carbohydrate metabolism
Increased cortisol, decreased insuiln sensitivity (hyperglycemia), decreased growth hormone can lead to obesity and diabetes.
Increased insulin resistance, decreased glucose sensitivity.
Forced Expiratory Volume
Maximal air exhale in 1 second.
Forced Vital Capacity
Maximal inhale and max exhale
Forced midexpiratory flow
Middle of forced exhalation (FEV0.25 - 0.75)
Diffusing capacity of the lung
How well O2 and CO2 is exchanged
Primary Pollutants
Exert physiological influence directly from source of pollution