So, I was reading my exercise physiology book and found this snippit. This is an exact quote from the book, with a reference if anyone cares to look it up.
"Recent research has shown that thyroxine is a powerful regulator of muscle fiber type (22, 27). Increase in blood levels of thyroid hormone above normal (hyperthyroidism) result in an increase in the percentage of fast muscle fibers. In contrast, a decreases in blood thyroxine levels (hypothyroidism) promotes an increases in the number of slow fibers in muscle."
The direct quote comes from:
Powers, S.K. and Howley, E.T. 2001. Exercise Physiology: Theory and Application to Fitness and Performance, 4th ed. 144. Champaign, IL: Human Kinetics.
The refernces are:
22. Caiozzo, V et al. 1993. Single fiber analyses of type IIa myosin heavy chain distribution in hyper and hypothyroid soleus. American Journal of Physiology. 265:C842-49.
27. Devor, S., and T. White. 1995. Myosin heavy chain phenotype in regenerating skeletal muscle is affected by thyroid hormone. Medicine and Science in Sports and Exercise 27:674-81.
"Recent research has shown that thyroxine is a powerful regulator of muscle fiber type (22, 27). Increase in blood levels of thyroid hormone above normal (hyperthyroidism) result in an increase in the percentage of fast muscle fibers. In contrast, a decreases in blood thyroxine levels (hypothyroidism) promotes an increases in the number of slow fibers in muscle."
The direct quote comes from:
Powers, S.K. and Howley, E.T. 2001. Exercise Physiology: Theory and Application to Fitness and Performance, 4th ed. 144. Champaign, IL: Human Kinetics.
The refernces are:
22. Caiozzo, V et al. 1993. Single fiber analyses of type IIa myosin heavy chain distribution in hyper and hypothyroid soleus. American Journal of Physiology. 265:C842-49.
27. Devor, S., and T. White. 1995. Myosin heavy chain phenotype in regenerating skeletal muscle is affected by thyroid hormone. Medicine and Science in Sports and Exercise 27:674-81.
