We have all experienced the heart-racing moments while watching a scary movie. You may even remember that one horror movie scene that made you jump out of your seats and haunted you for the rest of your childhood. Maybe it is when the alien ran through the corn maize in Signs or when the little girl crawled out of the television in The Ring, there is a reason why horror movies are called nightmare fuel.  Scary films have a way of making us scream, sweat and panic. The scarier the movie, the more our body reacts. While adrenaline junkies love the rush, others avoid it at all costs. Here's what scary movie does to our system.

1. Your Heart Rate Races and Blood Pressure Increases

When you sense danger, your body activates a flight response so that you can have the energy to move away or fight back. Anxiety can also activate the same response, so even if there is no danger your mind creates the same feeling. This results in an increase in your heart rate, blood pressure and blood flow to the muscles. So even if you are safe on your couch, you will start to sweat and breathe faster.

2. Your Muscles Tense Up and You Get Eerily Still

Did you ever find yourself clenching your limbs or gripping the armrest while watching a scary movie? Muscle tension is another way your body responds to a perceived threat. The fear causes your muscles to contract and tense up, preparing your body for a reaction. You may find yourself tense up in the theatre seat just like the girl hiding in the closet onscreen. You might even hold your breath but your tensed muscles will relax once the scene is over.

3. You Are More Alert and Have Heightened Senses

Various research suggests that watching horror movies release neurotransmitters that can increase brain activity and make you more alert for a while. So don't be surprised if you get freaked out by the slightest sound in your room. Anxiety Disorders Could be Related to Evolutionary Changes in the Human Brain, Finds New Study

4. You Might Get Nauseous

If you feel an intense bout of nausea or your bowel pressure coming on, your body might be pressing the 'purge system' button to get rid of the excess waste and run away. It’s totally normal if you feel the need to excuse yourself to a restroom while sitting in the theatre. Common Anxiety Triggers and Ways to Deal with Them

5. Your Immune System Works Harder

According to a study performed by the Coventry University, watching an unnerving movie causes your body to produce more white blood cells in the blood and higher hemoglobin concentrations. This suggests that your immune system is in an overdrive while trying to protect your body from stress. How to Overcome Social Anxiety? 4 Helpful Tips to Calm You Down

6. You Might Suffer a Heart Attack

A movie cannot scare you to death but in extremely rare cases, a pre-existing heart condition has been showed to cause heart attack from watching horror movies. If you have heart problems, you should avoid increasing your heart rate above a level from any activity. Whether it is a scary movie, sex, or exercise, if you cannot tolerate high heart rate, the flight response can be harmful for you.

Bottomline - For most people, the spikes in blood pressure and heart rate from watching a hair-raising movie is not an issue. Your body will return to normal after the movie ends.

(The above story first appeared on LatestLY on Jan 14, 2020 11:59 AM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).