Our body shivers when cold in an attempt by the body to warm itself up. Whenever our skin temperatures start dropping the brain communicates with the muscle fibers of a particular layer and instructs it to contract and relax rapidly. When this muscle is active, it heats our bodies. Shivering is one of the most powerful ways of generating heat, but it is also very demanding on energy inputs. Therefore, it is common to experience fatigue or lack of energy after we shiver very much over a period of time. Here is a more detailed explanation of how shivering works:  

• The hypothalamus is part of the brain that controls body temperature and receives signals when our skin gets cold. These signals are then sent by the hypothalamus to the muscle to contract and relax rapidly. Heat is generated through thermogenesis by means of this muscular activity. Blood distributes the heat energy produced during thrombogenesis over the entire body. Shivering can be triggered by a number of factors, including Cold exposure, Hypothermia, Fever,  Certain medications, and Some common medical conditions (e.g., Parkinson’s disease and multiple sclerosis).  
• Shivering is a healthy reaction to exposure to coldness. Nevertheless, excessive and prolonged shivers imply the need for seeking health care services. This could also imply hypothermia which is quite a severe health problem. 
• Here are some ways to prevent shivering:

* Dress warmly in layers. Make sure you wear hats, gloves, and scarves. When you are outdoors; cover your mouth and nose for cold weather.

* Do not get yourself too involved in hard physical exerts during extremely cold weather conditions.

* Drink warm liquids.

* Eat a warm meal. If you do start to shiver, there are a few things you can do to warm up

* Put on more clothes.

* Drink a warm beverage. Hot showers/baths. You can choose to cuddle with a pet or with another person.

* Exercise lightly. Consider sitting or lying in a warm location.