Fatigue is a feeling most athletes experience at some point in their athletic careers, whether it's at the end when their bodies just won't hold up to the expectations any more or for some other reason, such as poor conditioning, chronic illness or injury, a lapse in nutrition or sleep, or some other cause. Exercise Science researchers at the University of New Mexico define fatigue as simply the "inability to continue exercise at a given intensity." Of course, there are myriad reasons for the onset of fatigue, some of which are controllable, while others are harder to prevent or overcome.
Poor Conditioning
If you don't engage in regular physical exertion, your muscles can grow weak, leaving you feeling tired and fatigued, according to the University of Washington Department of Orthopaedics and Sports Medicine. This is why athletes who compete at high levels train throughout the year. Their training regimens vary during their competitive seasons and in their off-season workouts, of course, but the goal is always to remain fit and in healthy condition so they don't need additional time to get ready for the start of their seasons.
Insufficient Sleep
The National Sleep Foundation reports that one of the most common sources of fatigue is self-imposed sleep deprivation. We simply don't get the amount of sleep our bodies require on a regular basis. While an individual's sleep needs change throughout life and differs from other people's, research in the August 2010 issue of the journal "Sleep" showed that seven hours of sleep per night is best for a healthy heart and overall health, according to CBS News.
Emotional Causes
The University of Washington reports that depression can leave you feeling tired and fatigued and unmotivated to compete. You may be in good shape, but if you are feeling depressed, you're not likely to compete at your best. Another emotional reason may be the sense of unwillingness to accept limits on your abilities. Denying pain or other signs that you should ease up, while you overextend yourself will leave you fatigued. Developing a realistic understanding of your fitness level and ability to compete will help keep you healthy enough to compete at the optimal level for your age, health and skill level.
Poor Mechanics
The way an athlete runs or moves in his sport can affect his endurance. This is especially true of runners, who must work to make their strides as efficient as possible to have the energy and muscular strength to finish strong in a race. Videotaping yourself in action or having a trainer or coach watch you can help smooth out your performance so you won't expend extra energy needlessly. Poor mechanics can also stem from muscle or joint pain that causes you to move or try to move in a way that causes less pain, the University of Washington notes. The result of favoring other body parts, however, can be strains and ultimately fatigue.
