A certain degree of fatigue is normal in an athlete training hard for their sport or event. However, excessive and persistent fatigue and feelings of lethargy with a reduced sporting performance, often indicate a more serious problem. Overtraining, illness, and diet maybe some of the possible causes of chronic fatigue, but each person needs to be assessed in terms of their individual circumstances.
There are many possible causes of chronic fatigue and in order to narrow down the possibilities the coach or sports medicine practitioner must ask the right questions:
- Is there a constant feeling of fatigue, or does this occur before or after training/competition, at a particular venue (may suggest an allergy) or in warm weather (possible dehydration)
- Does the patient fall asleep
- How long has this tiredness been present? (try to establish if it first occurred after a competition, trip abroad or illness etc)
- Are there any associated symptoms? (a sore throat or a cold may indicate upper respiratory tract infection)
- Are there any respiratory symptoms (such as a post-exercise cough or chest tightness) which may indicate exercise-induced asthma or lower respiratory tract infection?
Causes of Fatigue
As already mentioned there are endless causes of persistent fatigue. Some of the most common are listed here:
- Overtraining syndrome
- Viral illness
- Inadequate diet low in carbohydrate or protein intake
- Depletion of iron stores (Anaemia)
- Chronic fatigue syndrome
Other conditions to look out for:
- Exercise-induced asthma
- Jet lag
- Psychological stress
- Eating disorders
- Neuromuscular disorders
If the answer to the problem is not immediately apparent, as it is not with so many of these cases, investigations should be undertaken to get to the bottom of the problem.
In case the current fatigue problem is due to an undiagnosed medical condition, a thorough medical examination should be performed. This should include a complete medical history and subjective assessment of the current condition (including gastrointestinal, neuromuscular and menstrual (in females) symptoms).
An examination should include resting heart rate and blood pressure as standard, along with any other examinations the clinician feels may be beneficial.
Further investigations and tests may be necessary and can include:
- Urine tests (to test glucose and protein levels)
- Blood tests (haemoglobin, white cell count, urea, electrolytes, Vitamin B12, thyroid function)
- Chest x-rays / Electrocardiogram (ECG)
- Lung spirometry
Keeping a diary of the training performed each day, along with the symptoms and feelings of fatigue can be a key diagnostic aid. This can help to see if the athlete gets enough rest and if there has been a recent change in training methods, intensity or volume. The amount of sleep and rest should be recorded each day, as should social events and other commitments.
A nutrition diary should also be recorded daily and should include everything consumed, including supplements, drinks, and alcohol. This can help determine if the athlete eats enough in general, consumes adequate volumes of carbohydrate and protein to support their training or has any allergies or intolerances.