I'm keeping a record of basal body temperature.

Here's what you get on cortisol.

So this really spikes your cortisol.

An incident like this increases cortisol levels.

Get your testosterone up. Get your cortisol down.

And their cortisol levels go through the roof!

So what we find is that high power alpha males in primate hierarchies have high testosterone and low cortisol, and powerful and effective leaders also have high testosterone and low cortisol.

Sorry about that. I've just given you a shot of cortisol, your fight flight hormone.

Cortisol floods the brain it destroys hippocampal cells and memory, and can lead to all kinds of health problems.

like cortisol, adrenaline and dopamine, increase the level of mood enhancing hormones like endorphins, and reduce overall blood pressure.

Cortisol is a major stress hormone involved in making skin cells churn out oily lipids from special glands called sebaceous glands.

Physiologically, there also are differences on two key hormones testosterone, which is the dominance hormone, and cortisol, which is the stress hormone.

And in the review, what they were interested in seeing is what kind of stresses most reliably raise levels of cortisol, the central stress hormone.

The brain has goals, basically, to feel good, to move towards reward, which is a dopamine release, to stay away from threat, which is a cortisol release, etc.

We have, from the time we are slapped on the butt until we take our last dying breath that's when we're newborn to when we're dead we cannot reduce our metabolic rate below what's called a standard, or basal metabolic rate.

Anyway, we would fill up with our own adrenaline and our own cortisol, and then we'd kill or be killed, we'd eat or we'd be eaten, and then suddenly we'd de fuel, and we'd go back to normal.

This triggers the pituitary gland, a pea sized gland found at the base of the brain, to release adrenocorticotropic hormone which then stimulates the adrenal gland sitting on top of the kidneys to release cortisol, the major stress hormone.

So we know that in primate hierarchies, if an alpha needs to take over, if an individual needs to take over an alpha role sort of suddenly, within a few days, that individual's testosterone has gone up significantly and his cortisol has dropped significantly.