Physical exhaustion may be accompanied by many symptoms. According to a New York Times article published online in February 2008, fatigue or exhaustion is one of the most common health problems and can signal the presence of various medical problems. The article notes that one in four people suffer from general fatigue not linked with a significant medical condition.
Impaired functioning, including decreased reaction time, awareness and ability to exercise appropriate judgment, is a common physical exhaustion symptom. According to Canada's Northwest Territories Department of Transportation, physical exhaustion is a contributing factor in 19 percent of fatal motor vehicle accidents, and is the cause of approximately 20 percent of non-fatal crashes. Physical exhaustion reduces reaction time, which can affect a driver's ability to stop in time to avoid an accident, and can significantly hamper a person's ability to perform the fine motor movements required for athletic activities. Decreased awareness due to physical exhaustion means that a person is not fully aware of his surroundings. Physical exhaustion can also impair a person's judgement, causing him to make poor decisions that could endanger his life or the lives of others.
Pain is a common symptom of physical exhaustion. Physical exhaustion-related pain can manifest throughout the body as generalized muscle pain, joint pain without swelling or redness or headaches. According to the National Institutes of Health or NIH, persistent pain can be both a symptom or a cause of fatigue or physical exhaustion. The NIH suggests that treating chronic pain will often help reduce fatigue. If a person is experiencing muscle pain and physical exhaustion simultaneously, he may be suffering from fibromyalgia. The National Fibromyalgia Association states that fibromyalgia is a syndrome, not a disease, and that fibromyalgia is characterized by chronic pain throughout the body, bilateral tender points in specific locations, sleep disturbances and fatigue. Severe cases of fibromyalgia can be debilitating and affect a person's ability to perform his basic activities of daily living.
Autonomic Nervous System Problems
According to the NIH, the autonomic nervous system, or ANS, governs a body's involuntary actions, such as the beating of the heart and the dilating and constricting of blood vessels. The ANS immediately responds to any type of stress that threatens to unbalance a person's body; there are connections between the ANS and the endocrine system that controls hormone secretion. When something in the autonomic nervous system goes awry, it can cause serious health problems. Physical exhaustion may affect the ANS and contribute to bladder problems, heart palpitations, shortness of breath, nausea or lightheadedness. According to a 2002 study by T. Watanabe and colleagues published in the "International Journal of Behavioral Medicine," smoking and overworking, including making frequent business trips, can amplify the autonomic dysfunction associated with vital exhaustion—a condition characterized by excessive fatigue, lethargy and irritability.