The effects of bed-rest and countermeasure exercise on the endocrine system in male adults: evidence for immobilization-induced reduction in sex hormone-binding globulin levels
Data(s) |
01/01/2012
|
---|---|
Resumo |
BACKGROUND AND AIM: There is limited data on the effects of inactivity (prolonged bed-rest) on parameters of endocrine and metabolic function; we therefore aimed to examine changes in these systems during and after prolonged (56- day) bed-rest in male adults. SUBJECTS AND METHODS: Twenty healthy male subjects underwent 8 weeks of strict bed-rest and 12 months of follow-up as part of the Berlin Bed Rest Study. Subjects were randomized to an inactive group or a group that performed resistive vibration exercise (RVE) during bed-rest. All outcome parameters were measured before, during and after bed-rest. These included body composition (by whole body dual X-ray absorptiometry), SHBG, testosterone (T), estradiol (E2), PRL, cortisol (C), TSH and free T3 (FT3). RESULTS: Serum SHBG levels decreased in inactive subjects but remained unchanged in the RVE group (p<0.001). Serum T concentrations increased during the first 3 weeks of bed-rest in both groups (p<0.0001), while E2 levels sharply rose with re-mobilization (p<0.0001). Serum PRL decreased in the control group but increased in the RVE group (p=0.021). C levels did not change over time (p≥0.10). TSH increased whilst FT3 decreased during bed-rest (p all ≤0.0013). CONCLUSIONS: Prolonged bed-rest has significant effects on parameters of endocrine and metabolic function, some of which are related to, or counteracted by physical activity. |
Identificador | |
Idioma(s) |
eng |
Publicador |
Springer |
Relação |
http://dro.deakin.edu.au/eserv/DU:30071063/belavy-effectsofbed-2011.pdf http://link.springer.com/article/10.3275/7606 |
Direitos |
2011, Springer |
Palavras-Chave | #Science & Technology #Life Sciences & Biomedicine #Endocrinology & Metabolism #Spaceflight #microgravity #inactivity #Berlin Bed Rest Study #WHOLE-BODY VIBRATION #MIDDLE-AGED MEN #SKELETAL-MUSCLE #HYPOGONADAL MEN #SIMULATED WEIGHTLESSNESS #RESISTANCE EXERCISE #NUTRITIONAL-STATUS #PHYSICAL-ACTIVITY #IMMUNE-RESPONSES #CREW MEMBERS |
Tipo |
Journal Article |