Rigor mortis is a chemical cadaveric phenomenon that affects the muscles and nerves of the human body after death, it can arise in various types of cases, mild, medium or complete, it occurs within the first 12 hours after death, that is my summary explanation of what it consists of, but to make it easier to understand what you have not yet heard of the subject, basically it is that a body can have movements after being dead or very strange things can happen to it, the truth, (it can raise the arms, legs or chest) in other cases they even have erections haha. I will tell you my anecdote of when I met him, the truth really shocked me a lot, I was starting to work in a funeral home of a relative, my goal since I was a child was to study criminalistics, and when I wanted that I knew that I had to prepare myself for what I would see so I wanted morbidly I began to experiment and I had the opportunity to know the work of thanatosesthetics, that was approximately at my 15 years of age, the story of how I started I will leave it for another post. Anyway, getting to the point. I had already been working for about 2 years, I felt quite experienced in many cases. One day an elderly lady arrived who had died of a cardio-respiratory arrest, she was very, very thin, even to the fact that it would be somewhat scary to see her by her features, after preparing everything to raise her to the work table I see that her neck It begins to have slight but very rare movements, it was from the left side to the right, very very slowly, I did not pay attention to it, I had no knowledge of this phenomenon, after starting work after half an hour, very very suddenly without waiting for it I raise both arms abruptly Imagine how pale I got, I threw myself to the ground seeing how he extended his arms like a zombie haha he kept them up for about 6 minutes or more without fixing any other position, I obviously wanted to get out, it was late and I did not want to disturb no other worker, so I called my brother I told him and nothing was scared too, then I had the great idea to search the internet that it could be about random movements in corpses hahaha, and there I managed to read about rigor mortis, when I plucked up the courage again to enter the funeral home, the lady was still with her arms outstretched, what I did was lower them and massage them a little to loosen them since the stiffness I had was already quite hard for The time I had been deceased, other cases have happened to me but never one like that, what would you feel if something like this happened to you? In my work you must be cold and calm regarding religious issues but I never had to see something like that to which I had no explanation hahaha I really thought I was possessed or something like that. Thanks to the internet, I no longer almost died of a fright when I had an ocsiso with that phenomenon, the world of thanatology is something very interesting and wonderful, I have been in hive little by little, I hope little by little people will read, I would love to answer Questions and talk about many other topics, I know this is very short but it is the first thing I write about this topic, thank you very much everyone, the image is taken from where I took a mini summary of the scientific explanation of rigor mortis, here the link 
English translation done here
https://www.abc.es/traductor/?ref=https%3A%2F%2Fwww.google.com%2F
ESPAÑOL
el rigor mortis es un fenomeno cadaverico quimico que afecta a los musculos y nervios del cuerpo humano luego de fallecer , puede surgir en varios tipos de casos , leves , medios o completos , se da entre las primeros 12 horas luego del desceso , esa es mi explicacion resumida de lo que consiste , pero para ponerlo mas facil de entender a lo que aun no habia oido del tema , basicamente es que un cuerpo puede tener movimientos luego de estar muerto o le pueden suceder cosas muy raras la verdad , ( puede levantar los brazos , piernas o el pecho ) en otros casos tienen hasta erecciones jaja.
les contare mi anecdota de cuando lo conoci , la verdad me shockee mucho , estaba comenzando a trabajar en una funeraria de un familiar , mi meta desde niño era estudiar criminalistica , y al querer eso supe que debia preparame para lo que veria asi que quise morbosamente comenzar a experimentar y tuve la oportunidad de conocer el trabajo de los tanatoesteticos , eso fue aproximadamente a mi 15 años de edad , la historia de como empeze la dejare para otro post. en fin yendo al grano .
ya tenia como 2 años trabajando me sentia bastante experimentado para muchos casos.
un dia llego una señora mayor que habia fallecido de un paro cardio-respiratorio , estaba muy muy delgada , hasta el hecho de que daria algo de miedo verla por sus facciones , luego de preparar todo para subirla a la mesa de trabajo veo que su cuello comienza a tener movimientos leves pero muy raros era del lado izquiero al derecho muy muy lentamente , no le preste atencion no tenia conociemiento de ese fenomeno , luego de comenzar el trabajo al cabo de media hora , muy muy derepente sin esperarmelo levanto los 2 brazos bruscamente , imaginense lo palido que me puse , me tire al suelo viendo como alargaba sus brazos como si fuera un zombie jaja los mantuvo arriba como unos 6 minutos o mas sin fijar ninguna otra posicion , yo obviamente busque salirme , era tarde y no queria molestar a ningun otro trabajador , asi que llame a mi hermano le conte y nada tambien se asusto , luego tuve la gran idea de buscar por internet de que se podia trata movimientos randoms en cadaveres jajaja , y ahi consegui leer sobre el rigor mortis , al armarme de valor de nuevo para entrar al tanatorio la señora aun seguia con los brazos extendidos , lo que hice fue bajarlos y masajearlos un poco para que se aflojaran ya que la rigidez que tenia era bastante dura ya por el tiempo que llevaba fallecida , me han pasado otros casos pero jamas uno asi como ese , que sentirian ustedes si les sucediera algo asi ? en mi trabajo debes ser frio y calmado respecto a los temas religiosos pero jamas me toco ver algo como eso a lo que no tuviera explicacion jajaja realmente pense que estaba poseida o algo asi. gracias al internet ya no me e vuelto a casi morir de un susto al tener un ocsiso con ese fenomeno , el mundo de la tanatologia es algo muy interesante y maravilloso , llevo poco en hive espero poco a poco la gente vaya leyendo , me encantaria responder preguntas y hablar de muchos otros temas , se que es muy corto esto pero es lo primero que escribo de este tema , muchas gracias a todos , la imagen es tomada de donde saque un mini resumen de la explicacion cientifica del rigor mortis , aca el link 