The growth hormone adaptation to short-term sprint exercise training

UNCG Author/Contributor (non-UNCG co-authors, if there are any, appear on document)
Jason Kyle Smith (Creator)
Institution
The University of North Carolina at Greensboro (UNCG )
Web Site: http://library.uncg.edu/
Advisor
Laurie Wideman

Abstract: The response of growth hormone to acute exercise has been shown to be altered by training. The present study examined the time course of GH adaptation to 3-weeks of sprint exercise training on a cycle ergometer. Eight, recreationally active, male subjects (age = 26.8 ± 4.3 yrs; height = 1.77 ± 0.05 m; weight = 77.79 ± 7.35 kg; lean body mass = 62.0 ± 7.1 kg) completed a 2-hour resting profile and a 2-hr acute sprint profile, followed by three weeks of training with additional acute sprint tests at the end of each week. Blood samples were taken every 15 minutes [Q15] during rest and more frequently [Q1-Q10] during exercise. Body composition was assessed by DXA [Prodigy Advanced, GE Lunar]. Training consisted of 4-6 repetitions of 30-second maximal sprints relative to body mass, three times per week. Integrated 2 hr serum GH area under the curve (AUC) was calculated using trapezoidal integration. Peak power (PP) increased 7.5% while time to peak power (TTP) decreased 58.0 % (P < 0.05) over the 3-week training period. The mean of 2 hr GH AUC per unit lean body mass (LBM), did not significantly decrease (P = 0.82) during the 3-week sprint training protocol, although a trend was observed for GH AUC to decrease from the first acute sprint test to the second acute sprint test (8.45 ± 3.0 ng/ml vs. 3.59 ± 1.21 ng/ml, respectively; P = 0.90). While this trend was similar to previously reported findings, we conclude that 3-weeks of sprint training does not significantly alter the GH AUC response to acute sprint exercise despite significant increases in power output during this same time frame.

Additional Information

Publication
Thesis
Language: English
Date: 2012
Keywords
Cycling, Growth Hormone, Sprint Exercise, Training
Subjects
Somatotropin $x Physiological effect
Cycling $x Physiological aspects
Physical education and training $x Physiological aspects

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