Brief Answer:
Increased Intracranial pressure

Detailed Answer:
Thank you very much for asking your question on this network. Your complaint is a common one and I say many people who refer the same type of phenomenon. This is nothing terribly serious and there is no reflection by this pain on anything that is mortally wrong with your heart, brain, or anywhere else.

What happens when we bend over for any reason is that we automatically increase the pressure that is within the head. It's essentially FLUID PRESSURE. There is fluid within the skull cavity which bathes the brain and spinal cord. Upon bending over or flexing at the hips there is an INCREASE in this fluid pressure. You may have even felt a fullness in your head on occasion or especially if your sinuses become filled up during allergies or whenever you've had a respiratory infection of the upper passages....you have felt what that sensation is like.

At the same time that there is an increase in this INTRACRANIAL (inside the cranium) PRESSURE there is a large INFLUX of blood into the BLOOD VESSELS which feed the brain and this causes an engorgement of those vessels....so they bulge a bit...or STRETCH if you will.

Now, keep in mind the blood that rushes into the cranial vault at the same time that this fluid pressure increases is FULLY CONTAINED WITHIN THE BLOOD VESSELS...we are not talking about a situation where the blood is escaping or popping through the vessels or anything like that....just so you keep the perspective.

As the BLOOD VESSELS expand or engorge with the blood inside of them and there is this sudden increase in volume or swelling and the vessel walls STRETCH....this causes a concomitant STRETCHING of the blood vessels which feed and travel within the COVERING OF THE BRAIN ITSELF which are called MENINGES. The stretching of the blood vessels therefore, in the brain due to volume increases is automatically accompanied by a similar INCREASE in blood pressure and volume in the COVERING OF THE BRAIN called the meninges. And again, there is a stretching or swelling that occurs......all of this based upon the act of BENDING OVER AT THE HIPS.

So far so good?

When the MENINGES SWELL AND STRETCH which cover the brain they activate a network of nerves which are distributed throughout the meninges designed to MEASURE THIS STRETCHING phenomenon. It's the body's sensor system so that it can respond appropriately to when things have "stretched enough" so that other things can happen in order to compensate and keep the fluid flowing. Of course, if you stay down in the bent over position too long and the pressure continues to build or stays up there.....things start to get uncomfortable.....so one of the things that the body might do in order to try and coax you to GET OUT OF THAT POSITION is send a bit of an uncomfortable feeling in the way of a pain, a stab, a poke, a jab to some part of your body.... to let you know that it doesn't like that position and for you to get out of it. Because this suddenly increase in pressure and swelling of brain vessels and coverings is in the head...well, the nearest thing that the body can activate to get your attention is SOME PART OF YOUR HEAD....maybe your temple, maybe the front of your head, maybe behind your eyes, maybe the base of your neck, the pain can literally be anywhere....or even in multiple places.....most people simply report one typical place where they are also seemingly sensitive. That changes from individual to individual. Of course, just as easily people can bend over and never experience such a pain as well.....Mother Nature for you at work keeping everyone guessing!

That is what the stabbing pain is believed to be all about in the temples. Sometimes it can be just on one side, other times it can be on both. It just depends upon which side the network of nerves is activated by the meningeal stretch or which vessels on which side may be engorged a bit more or are more full than the other which determines which side you get the pain on.

However, all in all....this is a natural response that the body has to get you to understand that it wants you out of that position as quickly as possible so that the increased intracranial pressure and the increased blood volumes in the brain and in the meninges can reduce and get back to normal. it's not dangerous, it's not a warning sign of a stroke or aneurysm.....it's just your body telling you to STRAIGHTEN UP please.

If I've satisfactorily addressed your question then, could you do me the kindest of favors by CLOSING THIS QUERY and be sure to include some fine words of feedback and a 5 STAR rating to our transaction if you feel the response has helped you? Again, many thanks for posing your question.

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This query has utilized a total of 29 minutes of professional time in research, review, and synthesis for the purpose of formulating a return statement.

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