摘要：Stud ies on hormonal response to endurance training reveal conflicting res ults.The pur pose of thi s stu dy was to investigate the physiological effects of endurance training on ser um growth (GH),cortisol and thyroid hormones in female college students.An exercise group (EG,n =l 1;21.0 ± 2.4 yrs) performed enduran ce training for six weeks,3d ∕w k,30m in ∕d by runn ing on the treadmill at a speed requ iring 65-80% of their maximal heart rate reserve (HRRmax).The control group (CG,n=ll;21.8 ± 1.7 yrs) did not p erform enduran ce trainin g.Basal and pos t-training GH,cortisol,TSH,T3,T4,fΓ3 and fΓ4 levels were ass ess ed in serum samples.At the end of the training period,serum GH levels did not change in eith er group;T4 decreased (p<0.01) in EG,and cortisol increased (p<0.01) in CG.The change observed in TSH levels in the EG was lower than t ha t in the CG (p<0.05).The decreases in TSH,fΓ3 an d T4 could be attrib uted to a lower h ypothalam ic-pituitary signaling action t ha t c ould be the result of energy conserv ation in the exercising subjects,on could result from the better regulation of oxidative processes.Post-training cortisol levels increased in both groups,bu t the smaller increas e observed in the EG when com pared to the CG might be th e r esult of better s tre ss management.
