Thyroid and Whole Body Vibration

Thyroid and Whole Body Vibration

The thyroid is an endocrine gland located in the inferior aspect of the neck. Its main functions are related to metabolism, protein synthesis, and control over the body’s level of sensitivity to other hormones. Thyroid hormones include thyroxine (T4), triiodothyronine (T3) and calcitonin. T4 and T3 help to control the rate of metabolism as well as the influence rate and growth of function of other systems in the body. Calcitonin is responsible for maintaining the proper amount of calcium in the body, known as calcium homeostasis.

The most common problems related to the thyroid are hyperthyroidism (overactive thyroid) and hypothyroidism (underactive thyroid). Hyperthyroidism results in an overactive thyroid gland which leads to an excessive amount of T4 and T3 within the body. The excess thyroid hormones heighten the effects of the sympathetic nervous system. Graves’ disease is an autoimmune disease that is a common cause of an overactive thyroid. The thyroid becomes enlarged and over stimulated resulting in symptoms including protruding eyes, heart palpitations, sweating, diarrhea, muscle weakness and a sensitivity to heat. Treatments include antithyroid drugs, radioiodine, and surgery to remove the thyroid. Hypothyroidism can be caused by an iodine deficiency, following childbirth (post partum thyroditis), autoimmune disease (Hashimoto’s thyroditis), removal of the thyroid gland, and decreased production of thyroid stimulating hormone from the pituitary gland. Symptoms of an underactive thyroid include weight gain, slow heart rate, brittle hair and nails, fatigue, sensitivity to cold, decrease in muscle tone, depression, and muscle cramping and joint pain. An individual with an underactive thyroid is usually treated with hormone replacement therapy. Cancers of the thyroid gland result in painless masses in the neck and are usually are asymptomatic. They are treated by surgery.

Exercise is an important aspect of treatment for hypothyroidism as it helps to stimulate secretions from the thyroid gland, while also increasing the body tissues sensitivity to thyroid hormones. Due to symptoms of fatigue, individuals with an underactive thyroid may find it difficult to exercise. To deal with fatigue, breaking up exercise into shorter bouts throughout the day may help an individual participate in physical activity. Due to the thyroid hormones effect on the heart, individuals with hyperthyroidism may have a decreased exercise tolerance secondary to tachycardia, which will commonly cause a resting heart rate of above 90 beats per minute. During exercise at the anaerobic threshold, diminished work efficiency on a cycle ergometer was found in individuals with hyperthyroidism 1. It is felt that this diminished work efficiency reduces exercise tolerance 1.

There is a lack of research examining the effects of Whole Body Vibration (WBV) on individuals with thyroid conditions. Tumours and cardiac arrhythmias are considered contraindications to using WBV. Contraindications are recommended due to the lack of research in a particular area, or when there is a known consequence. Without the research, it cannot be determined if the benefits to using WBV would outweigh any potential risks. Contraindications are also present to ensure that an individual discusses WBV with his/her physician. Given the medical history of the individual, a physician can assess the possible benefits and risks of WBV. A physician should be familiar with WBV so they can assist the

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individual in making the decision to use the platform. Although findings are varied, there appears to be a trend showing that WBV increases certain hormones in the blood; however thyroid hormones were not among the hormones analyzed 2, 3. Hyperthyroidism is possible concern regarding WBV, as hormones are elevated by using the platform and may impact an individual’s symptoms. However, until research is done to specifically look at thyroid hormones, the risks and benefits of using WBV with a thyroid condition (more specifically hyperthyroidism) cannot be determined.

Once a physician has cleared an individual to use WBV, they should begin training bouts at a lower intensity and duration. Also, symptoms should be continuously monitored. WBV should be discontinued if any symptoms related to their thyroid condition become worse, and any changes should be discussed with a physician. Once an individual has become comfortable with the machine, and no changes in symptoms occur, the intensity of exercises can be increased and exercises at the appropriate level may be added. In general, if an individual experiences shortness of breath, pain or dizziness when using WBV it should be discontinued immediately.

References

1. Kimura H, Kawagoe Y, Kaneko N, Fessler HE, Hosoda S. 1996. Low efficiency of oxygen utilization during exercise in hyperthyroidism, Chest, 110, 1264-1270.

2. Kvorning T, Bagger M, Caserotti P, Madsen K. 2006. Effects of vibration and resistance training on neuromuscular and hormonal measures, European Journal of Applied Physiology, 96(5), 615-25.

3. Bosco C, Iacovelli M, Tsarpela O, Cardinale M, Bonifazi M, Tihanyi J, Viru M, De Lorenzo A, Viru A. 2000. Hormonal responses to whole-body vibration in men, European Journal of Applied Physiology, 81(6), 449-54.

Various models and machines on the market have been used for the purpose of conducting research. Also, a variety of frequencies (speeds) and amplitudes (platform variation) which may or may not be known to us have been used. We do not guarantee or claim users will achieve similar results with our T-Zone Whole Body Vibration machine.

THIS IS FOR EDUCATIONAL PURPOSES ONLY. WE DO NOT DIAGNOSE OR PRESCRIBE. PLEASE CONSULT YOUR HEALTH PROVIDER.

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