Your brain needs a constant supply of blood and it doesn’t take kindly to periods of deprivation! Even small periods of blood starvation can cause brain cell death with the most common causes being a Cerebrovascular accident (CVA) aka stroke, and mercifully less frequent causes including Traumatic Brain Injury (TBI) and suffocation or drowning. Anyway, off of this morbid subject, but the reason for me mentioning this is because blood flow to the brain is absolutely integral, and the constant flow in a relatively concentrated space is one of the reasons why the brain is hotter than the rest of your body. So the polarity and magnitude of temperature difference between the brain and body is effected by some of the traumatic events as mentioned above, but more pertinently the temperature of your brain significantly increases because of exercise.
Effect of exercise on brain temperature
When we exercise our bodies temperature rises, consequently our Blood Brain Barriers permeability changes resulting in leakage meaning toxins can enter the brain (this is also a risk of overtraining). So ultimately, exercise leads to elevated brain temperature which in turn causes central nervous fatigue, you might have noticed your veins protruding from your head during exercise, this is because of the preferential shift of arterial blood to the brain in order to help cool it down!
So avoid being a ‘hot head’ when training by bringing your brain temperature back down as efficiently as possible by having a cool shower or immersing yourself in cold water after exercise or between events.
Childs, C, et al. (2013). Clinical review: Brain-body temperature differences in adults with severe traumatic brain injury. Critical Care. 22;17(2)Retrieved 28th August, 2013, from Discount Supplements