Approximately 27 million Americans have overactive or underactive thyroid glands, although more than half remain undiagnosed, according to the American Association of Clinical Endocrinologists. Some patients turn to alternative therapies and lifestyle changes such as exercise to help cope with the symptoms of thyroid disease. Although exercise has definite effects on the thyroid, don't rely on it alone to treat your condition; check with your doctor to see if you need medication.
Identification
The thyroid is a butterfly-shaped gland in front of your trachea, below the larynx. The thyroid produces the hormones iodothyronine, known as T3, and thyroxine, or T4, both of which travel though blood to all tissues of your body. These hormones regulate how your body breaks down food for energy, the consumption of oxygen and how much heat your body needs. Thyroid disorders include hyperthyroidism, or Grave's disease, where too much thyroid hormone is produced; hypothyroidism, with too little hormone; thyroid nodules, or lumps; thyroiditis, or inflammation; and cancer.
Exercise Considerations
Thyroid disorders are often characterized by exercise intolerance, with fatigue setting in easily and muscles and joints aching more than in a healthy individual. Respiration can be impaired, leading to short supplies of oxygen, and muscles have a hard time strengthening in response to activity. Thyroid conditions can also cause higher heart rates.
Exercise Effects
Exercise performed at the anaerobic threshold, or 70 percent of maximum heart rate, causes the most dramatic rises in the rates of T3 and T4, but at 90 percent of maximum heart rate, levels of T3 start to fall, according to a study published in December 2005 in "Neuroendrocrinology Letters." Another study published on Chiro.org by Greg Kelly, ND, reported that T3 hormone levels increased in female nonathletes after exercise but decreased following exercise in female athletes. Evidence also suggests that if an athlete's exercising exceeds his caloric intake, then it can cause low T3 levels.
Exercise Benefits
Regular exercise will improve your cardiovascular system and possibly muscle tone, helping you feel better. Weight-bearing exercise such as walking or running is important if you have Graves' disease to prevent bone loss that can occur. Hypothyroid patients are often plagued by weight problems, and exercise promotes caloric burn to prevent weight gain and increase energy levels.
Exercise also improves thyroid function by stimulating the production of thyroid hormone and making body tissues more responsive to the effects of thyroid hormones. A study of professional cyclists in Spain, published in 2001 in "Hormone Research," found that the weeks of competition provoked significant increases in basal thyroid hormone concentrations.
References
- The Hormone Foundation; Thyroid Disorders Overview; 2011
- "Neuroendrocrinology Letters"; Exercise Intensity and Its Effects on Thyroid Hormones; Figen Ciloglu, et al.; December 2005
- Chiro.org; Peripheral Metabolism of Thyroid Hormones: A Review; Greg Kelly, ND
- MayoClinic.com; Hyperthyroidism (Overactive Thyroid); Mayo Clinic Staff; December 2010
- ProQuest; Thyroid Hormone Disorders; Thyroid Hormone Disorders; Jennifer A. Phillips; May 2001
