Most doctors encourage you to exercise on a regular basis. Physical activity has a broad range of health benefits, including improved cardiovascular fitness and weight loss. The exact mechanisms underlying these effects remain unknown, but they could involve exercise-induced changes in hormone levels. Aerobic exercise, in particular, has positive effects on your endocrine system, according to a July 2011 review in the "Journal of Nutrition and Metabolism." Talk to your doctor before making lifestyle changes.
Swimming Decreases Melatonin
The pineal gland releases melatonin to regulate your sleep cycle. Patients with sleep disorders often have excess levels of melatonin, according to a May 2008 report in "Neuroscience Letters." Physical exercise might help correct this hormone imbalance by reducing melatonin production. A study described in the October 2010 edition of the "European Journal of Applied Physiology" tested this hypothesis in professional swimmers. The researchers measured melatonin before and after the athletes began "basic training." The aerobic exercise included in this training routine reduced the swimmers' melatonin levels.
Swimming Decreases Cortisol
The adrenal glands synthesize cortisol in response to stress. Young adults with elevated cortisol often become depressed, according to a July 2011 report in the "Journal of Affective Disorders." Aerobic exercise can act as an antidepressant in some cases. Decreases in cortisol might mediate depression. An experiment presented in the September 2011 issue of "Neuroscience" explored this possibility in an animal model of mental illness. Male rats predisposed to developing depression swam an hour a day for three weeks. This routine decreased their cortisol and prevented signs of depression.
Cycling Increases Testosterone
The testes produce testosterone to facilitate tissue building and repair. This anabolic hormone decreases with age, causing reproductive and sexual problems, according to a review published in the June 2010 edition of "Therapeutic Advances in Urology." Cardio exercise is known to slow the aging process -- an effect that may be mediated by enhanced testosterone. A January 2011 report in the "Journal of Strength and Conditioning Research" evaluated this idea in healthy adults. Participants worked out on a stationary bicycle for 30 minutes during a single testing session. This exercise protocol increased testosterone production.
Dancing Increases Progesterone
The ovaries manufacture progesterone to regulate the menstrual cycle. Levels of this hormone begin falling when women reach 30 years of age, according to a September 2005 report in "Menopause." This decline causes menopausal symptoms such as hot flashes and night sweats. Regular exercise might help by increasing progesterone. A study presented in the May 2011 issue of the "European Journal of Applied Physiology" tested this idea in postmenopausal women. Subjects danced three times a week for six months. This routine increased progesterone markers such as pregnanediol without causing side effects.
References
- "Journal of Nutrition and Metabolism"; Review of Weight Control Strategies and Their Effects on the Regulation of Hormonal Balance; Neil A. Schwarz, et al.; July 2011
- "Neuroscience Letters"; Circadian Rhythm in Salivary Melatonin in Narcoleptic Patients; Katerina Blazejova, et al.; May 2008
- "European Journal of Applied Physiology"; Urine Melatonin and Citrate Excretion During the Elite Swimmers' Training Season; Beatriz Diaz Lopez, et al.; October 2010
- "Journal of Affective Disorders"; Elevated Daytime Cortisol Levels; Mark A. Ellenbogen, et al.; July 2011
- "Neuroscience"; Molecular Aspects Involved in Swimming Exercise Training Reducing Anhedonia in a Rat Model of Depression; Andre Roberto Sigwalt, et al.; September 2011
- "Therapeutic Advances in Urology"; Hypogonadism, ADAM, and Hormone Replacement; Michael R. Pinsky, et al.; June 2010
- "Journal of Strength and Conditioning Research"; Plasma ...; John Hough, et al.; January 2011
- "Menopause"; Monitoring Reproductive Aging in ...; Rebecca J. Ferrell, et al.; September 2005
- "European Journal of Applied Physiology"; Effects ...; Maria Concepcion Robles Gil, et al.; May 2011
