Influence of 6-week, 6 days per week, training on

shiliangyin

From  M. Lehmann MD, K. Knizia MD, U. Gastmann MD, K. G. Petersen MD*,
A. N. Khalaf MD*, S. Bauer Dipl Oec Troph, L. Kerp MD* and J. Keul MD
Department of Sports and Performance Medicine and *Department of Endocrinology, University Clinic FreibergFreiberg,Germany
The influence on pituitary function of 6 weeks of training
on 6 days a week was examined in six recreational athletes.
Endurance training on a bicycle ergometer for 31-33 min
was performed on 4 days each week at 90-96% (weeks
1-3) and 89-92% (weeks 4-6) of the 4 mmol lactate
thresholds determined on day 0 and day 21, respectively,
with interval training of 3-5 x 3-5 min in addition on 2
days a week at 117-127% and 115-110%, respectively.
Determination of the serum hormone levels and a
combined pituitary function test (200 [ig thyrotropin
releasing hormone (TRH), 100 [tg gonadotrophin-releasing
hormone (GnRH), 100 [tg corticotrophin releasing hormone
(CRH), 50 [tg growth hormone releasing hormone
(GHRH)) were made before training, after 6 weeks of
training and after another 3 weeks of recovery. Training
increased performance at 2 mmol lactate by 25%, at 4 mmol
by 12%, and maximum performance by approximately
12%. The releasing hormone-stimulable prolactin, thyroid
stimulating hormone (TSH) and somatotrophic hormone
(STH) synthesis-secretion capacity remained unchanged,
the adrenocorticotrophic hormone (ACTH) was increased
after training. Cortisol release was reduced, folliclestimulating
hormone (FSH)-synthesis-secretion capacity
was increased after training, and the luteinizing hormone
(LH)-synthesis-secretion capacity reduced. This had no
influence on base or exercise-induced serum hormone
levels (cortisol, aldosterone, insulin, prolactin, FSH, LH,
TSH, ACTH, ADH and STH), which showed no dependence
on training, except for free testosterone which
showed a decreasing trend (P < 0.10) of 19-25% and
post-exercise ACTH which showed an increasing trend of
33% (P < 0.10). Conditioning (cortisol sensitivity and
ACTH response) or adaptation (FSH and LH responses) to
changed testosterone s