context: Medically speaking, fatigue is not the same thing as tiredness. Tiredness happens to everyone -- it is an expected feeling after certain activities or at the end of the day. Usually you know why you are tired and a good night's sleep solves the problem. Fatigue is a daily lack of energy; unusual or excessive whole-body tiredness not relieved by sleep. It can be acute (lasting a month or less) or chronic (lasting from one to six months or longer). Fatigue can prevent a person from functioning normally and affects a person's quality of life. According to the National Multiple Sclerosis Society, 80% of people with MS have fatigue. MS-related fatigue tends to get worse as the day goes on, is often aggravated by heat and humidity, and comes on more easily and suddenly than normal fatigue. The best way to combat fatigue related to your MS is to treat the underlying medical cause. Unfortunately, the exact cause of MS-related fatigue is often unknown, or there may be multiple causes. However, there are steps you can take that may help to control fatigue. Here are some tips: Evaluate your level of energy. Think of your personal energy stores as a "bank." Deposits and withdrawals have to be made over the course of the day or the week to balance energy conservation, restoration, and expenditure. Keep a diary for one week to identify the time of day when you are either most fatigued or have the most energy. Note what you think may be contributing factors. Be alert to your personal warning signs of fatigue. Fatigue warning signs may include tired eyes, tired legs, whole-body tiredness, stiff shoulders, decreased energy or a lack of energy, inability to concentrate, weakness or malaise, boredom or lack of motivation, sleepiness, increased irritability, nervousness, anxiety, or impatience. Plan ahead and organize your work. For example, change storage of items to reduce trips or reaching, delegate tasks when needed, and combine activities and simplify details. Schedule rest. For example, balance periods of rest and work and rest before you become fatigued. Frequent, short rests are beneficial. Pace yourself. A moderate pace is better than rushing through activities. Reduce sudden or prolonged strains. Alternate sitting and standing. Practice proper body mechanics. When sitting, use a chair with good back support. Sit up with your back straight and your shoulders back. Adjust the level of your work. Work without bending over. When bending to lift something, bend your knees and use your leg muscles to lift, not your back. Do not bend forward at the waist with your knees straight. Also, try carrying several small loads instead of one large one, or use a cart. Limit work that requires reaching over your head. For example, use long-handled tools, store items lower, and delegate activities whenever possible. Limit work that increases muscle tension. Identify environmental situations that cause fatigue. For example, avoid extremes of temperature, eliminate smoke or harmful fumes, and avoid long hot showers or baths. Prioritize your activities. Decide what activities are important to you, and what could be delegated. Use your energy on important tasks. Fatigue is often made worse if you are not eating enough or if you are not eating the right foods. Maintaining good nutrition can help you feel better and have more energy. Decreased physical activity, which may be the result of illness or of treatment, can lead to tiredness and lack of energy. Scientists have found that even healthy athletes forced to spend extended periods in bed or sitting in chairs develop feelings of anxiety, depression, weakness, fatigue, and nausea. Regular, moderate exercise can decrease these feelings, help you stay active, and increase your energy. Managing stress can play an important role in combating fatigue. Here are tips to help keep stress in check: Adjust your expectations. For example, if you have a list of 10 things you want to accomplish today, pare it down to two and leave the rest for other days. A sense of accomplishment goes a long way to reducing stress. Help others understand and support you. Family and friends can be helpful if they can "put themselves in your shoes" and understand what fatigue means to you. Support groups can be a source of comfort as well. Other people with MS understand what you are going through. Relaxation techniques. Audiotapes that teach deep breathing or visualization can help reduce stress. Participate in activities that divert your attention away from fatigue. For example, activities such as knitting, reading, or listening to music require little physical energy but require attention. If your stress seems out of control, talk to your doctor. They are there to help. Although fatigue is a common and often expected symptom of MS, you should feel free to mention your concerns to your doctors. There are times when fatigue may be a clue to some other underlying medical problem. Other times, there may be medical interventions that can prevent fatigue.