Please enable JavaScript.
Coggle requires JavaScript to display documents.
Thermoregulation (Body temperature regulation (Situatons causing a…
Thermoregulation
-
Exercise in the heat
‘Competition’ between blood supply to the active muscles and skin. The muscles need blood and the oxygen to sustain the exercise; the skin needs blood to facilitate heat loss to keep the body cool
-
-
Average-sized female athlete (50-75kg) may lose 1.6 to 2.0 L of sweat each hour during exercise in the heat.
High rate of sweating reduces blood volume : limits the volume of blood returning to the heart : increasing heart rate : decreasing cardiac ouput : reduces performance potential
-
-
-
Heat-related disorders
Muscle cramps: Warning signs: fatigue, excessive thirst, profuse sweating,
Heat exhaustion: Warning signs: nausea, chills or goose bumps, headache
Heatstroke: Warning signs: Cessation of sweating, confusion, loss of consciousness
Exercise in the cold
Primary means by which our body avoid excessive heat loss are peripheral vasoconstriction and (non)shivering thermogenesis
Body size is an important consideration for heat loss, both a higher surface area-to-mass ratio and a lower peripheral muscle mass or fat will increase the loss of body heat
-
-
Small muscles in the periphery like the fingers become cold, muscle function can be severely affected.
Prolonged exercise increases adrenaline and noradrenaline secretion : increases the mobilization and oxidation of fat as an energy source.
Cold exposure : triggers vasoconstriction : reduces blood flow to peripheral fat stores : impaired fat mobilization and oxidation
Muscle glycogen rates used at a higher rate in the cold than in warmer conditions : impaired endurance performance
Health risks
Hypothermia : drowsiness, lethargy and even coma
-
-
Exercise-induced asthma : Dying of the airways due to the combination of high respiration rate of exercise and the dry air as temperature drops
-
-
High humidity : high amount of water molecules in the air : decreased capacity to accept water molecules: limits sweat evaporation and heat loss
Low humidity : lower amount of water molecules in air : increased capacity to accept water molecules : ideal oppurtunity for sweat evaporation and heat loss
-
-
-
-
-
-