Atrophy
Atrophy.
When you squeeze your muscles really hard (like in a stunt) your muscles may shake because they're working so hard. It's totally normal, it happens to everyone.
Between 640 and 850 muscles in a normal human's body.
Normal nipple sensation is when it is stimulated then it will erect and constant stimulation makes the uterus contract.
You should try to keep calm and relax, your body will return to normal. If not consult a physician, they will give you an injection to relax your muscles.
Pre-ejaculation, whenever it occurs, is a normal thing. It can never really be abnormal, unless it is spontaneous and there is no sexual stimulation going on at the time. Kissing is definitely sexual stimulation and can cause pre-ejaculation.
If you exercise a lot, it should be totally normal to have larger muscles.
intercostal muscles
All the synovial joints that are used in normal daily activities, like the muscles and joints of the arms and legs.
A "strained"muscle is one that has been used more than normal, and is a voluntary muscle. Involuntary muscles are those that work without your having to think about it (heart for example) and are very difficult to "strain." Muscles that move when you choseto use them ( arms, legs) are more likely to suffer stress injuries.
Sex without a partner typically refers to masturbation, which is self-stimulation of the genitals to achieve sexual pleasure. It can be a healthy and normal part of an individual's sexual expression and can help relieve sexual tension or explore one's own body and desires.
In many jurisdictions, if caught, you must purchase a permit at twice its normal cost.