Body aches and fatigue are common symptoms of a variety of illnesses and conditions. While both terms are somewhat vague, body ache usually refers to soreness in the muscles, while fatigue is another word for lack of energy or exhaustion. In some cases, the presence of other symptoms can offer clues about the underlying cause of body aches and fatigue. Understanding the signs and symptoms of body aches and fatigue allows you to identify the problem quickly and find the most effective treatment.
An ache is a type of dull pain or soreness. Body aches usually involve pain in one or more muscles and can be either widespread or isolated to specific areas, such as the arms or legs. Activities like walking or stretching may aggravate muscle soreness in some cases, depending on the underlying cause.
According to the New York Times, muscle soreness can be caused by a variety of conditions, including injury and overuse, chronic fatigue syndrome, fibromyalgia or infections like the flu. The presence of additional symptoms like fever or general malaise may point to an infectious cause, while pain that is worse upon movement is sometimes injury-related.
Both body aches and fatigue can cause an overall decrease in mental and physical performance. Slowing of reaction time is a common sign of fatigue, as are carelessness and an increased frequency of mistakes or errors in work.
Mental fatigue—a type of exhaustion that affects cognition and emotions—has the ability to manifest physically as well. According to Science Daily, mentally fatigued people become physically exhausted more quickly when exercising, suggesting a link between the two conditions.
Because symptoms like body aches and fatigue are unpleasant, they can sometimes lead to negative mood changes like irritability or depressed mood. People who experience prolonged bouts of pain and fatigue—such as patients with fibromyalgia or chronic fatigue syndrome—are more likely to experience depression or other mood changes associated with their condition.
Changes in regular sleeping patterns are a possible sign of body aches and fatigue. In some cases, body aches may be severe enough to interfere with sleep, leading to insomnia and resulting fatigue. Likewise, fatigue can lead to an increased need for sleep and a tendency to sleep more than usual.