[Leptin: aspects on energetic balance, physical exercise and athletic amenorhea].
The aim of this manuscript was to review the knowledge about leptin, detailing its relationship with energetic intake and physical activity. Leptin is an adipocyte hormone, recognized mainly for its putative role in control of energy expenditure, food intake, body weight and reproductive function. Leptin has still important peripheral actions, including its role on the ovarian tissue. The intracellular signaling mechanisms are recognized in hypothalamus, but in peripheral tissue are not fully understood. The exercise, when practiced by women, if not appropriately planned according to food intake, can modify the leptin release. When energy imbalances induced by exercise and/or deficient food ingestion occurs, low leptin levels are observed, leading to a reduction in GnRH (gonadotropin-release hormone), in LH (luteinizing hormone) and FSH (follicle-stimulating hormone) in pituitary, and consequently a minor release of ovarian estrogens. This process is named hypothalamic amenorrhea, and has repercussions in the woman's health. In this perspective, it is important to emphasize the need to evaluate the energy expenditure from exercise and to formulate adequate alimentary plans to these individuals.
Ribeiro
Sandra Maria Lima
SM
Grupo de Estudos em Nutrição e Atividade Física, Programa de Pós Graduação Stricto Sensu em Educação Física da Universidade São Judas Tadeu, São Paulo. smlribeiro@uol.com.br
dos Santos
Zirlene Adriana
ZA
da Silva
Renata Juliana
RJ
Louzada
Eliana
E
Donato
José
J
Tirapegui
Julio
J
D000273:Adipose Tissue / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000568:Amenorrhea / Q000378:metabolism*; D015415:Biomarkers / Q000378:metabolism; D015992:Body Mass Index; D031204:Caloric Restriction; D002648:Child; D004032:Diet; D004734:Energy Metabolism / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007031:Hypothalamus / Q000378:metabolism; D020738:Leptin / Q000502:physiology*; D009765:Obesity / Q000378:metabolism; D013177:Sports / Q000502:physiology*
D015415:Biomarkers; D020738:Leptin