In addition, since isometric exercises are done in a static position, they won't help improve speed or athletic performance. They can be useful, however, in enhancing stabilization â maintaining the position of the affected area â since muscles often contract isometrically to aid in stabilization.
Etiology. Most (85-95%) substernal thyroid masses represent benign goiter. Historically, goiters have generally occurred because of iodine deficiency, although this is now observed primarily in developing nations.
Thyroid cysts are regions of the thyroid that are enlarged and filled with fluid. They may be small (1 cm) or sometimes very large and can develop slowly or arise suddenly. Thyroid nodules can also degenerate and become fluid-filled sacs entirely or have a combination of solid and cystic areas.