DESCRIPTIONMuscle weakness refers to the profound muscle weakness that may follow hard or unaccustomed exercise. Appropriate health care must be individualized according to the underlying disorder.
SIGNS & SYMPTOMSUnaccustomed exercise.
Symptoms that appear following a period of rest after the exercise, an hour or 2 later, or the next day. Frequently a child eats a high-carbohydrate meal after competition or vigorous physical exercise, followed by a night's sleep. The muscle weakness then appears the next day.
Weakness that begins in the child's legs and progresses to the arms or other muscles in the body. Disabling fatigue accompanies the muscle weakness.
CAUSESAn underlying inherited disorder called periodic paralysis that interferes with the child's muscle cellular metabolism.
Excessive exercise in hot weather with loss of water, sodium, and potassium, leading to dehydration.
Diuretic medications that cause sodium loss and excessive potassium loss through the child's kidneys. The sodium loss is desirable; the potassium loss is a significant undesirable side effect that may lead to major body disturbances. Customary doses of diuretics may require reduction during hot weather.
Decreased potassium levels in the circulating blood and muscle cells. The decreased potassium levels can be brought about by any of the following:
PREVENTING COMPLICATIONS OR RECURRENCEInstructions for your child:
Prevent potassium loss, increase fluid intake, and adjust exercise programs and medication dosages during hot weather.
Avoid the combination of diuretic medications, alcohol, and heavy exercise during exceptionally hot weather. This combination can be lethal, causing strokes and life-threatening episodes of irregular heart rhythms.
Increase potassium-rich foods in your diet.
Take potassium supplements (with a doctor's prescription) prior to vigorous exercise if you have had an exercise-induced muscle weakness in the past.
Modify your activity level to one below that which triggers attacks.
Your own observation of symptoms.
Medical history and physical exam by a doctor.
Blood studies (sometimes) to measure the child's potassium levels.
Permanently weakened muscle groups (rare).
Fear of recurrence, resulting in unwarranted abandonment of the child's exercise program.
Curable and preventable without long-lasting complications for your child by modifying the exercise program, taking potassium supplements, and avoiding dehydration.
Your child should replace lost potassium with supplements or increase high-potassium foods in the diet.
Your child should replace fluid loss with water instead of soft drinks.
After vigorous exercise, the child should avoid a high-carbohydrate meal.
Your doctor may prescribe potassium supplements for your child's muscle weakness.
If exercise-induced muscle weakness is a recurrent problem for your child, it may be necessary to cut back on the child's activity level permanently.
DIET & FLUIDSIf your child has a potassium deficiency, provide foods high in potassium, such as dried apricots, whole-grain cereal (hot or cold), dried lentils, dried peaches, bananas, peanuts, citrus fruits, or fresh vegetables.
Following a diet high in complex carbohydrates makes good nutritional sense to all those hoping to maintain or reach a good level of health and fitness. However, your child should not eat such a meal within 3 to 5 hours before competition, and should eat only lightly directly afterwards.
OK TO GO TO SCHOOL?Yes, when condition and sense of well-being will allow.
CALL YOUR DOCTOR IF
Your child has persistent or recurrent muscle weakness following exercise.
Your child develops new symptoms after starting any prescribed medicine. All effective medicines have potentially undesirable side effects. These can frequently be controlled by modifying the dosage.