Age is an important determinant of the growth hormone response to sprint exercise in non-obese young men.
BACKGROUND
The factors that regulate the growth hormone (GH) response to physiological stimuli, such as exercise, are not fully understood. The aim of the present study is to determine whether age, body composition, measures of sprint performance or the metabolic response to a sprint are predictors of the GH response to sprint exercise in non-obese young men.


METHODS
Twenty-seven healthy, non-obese males aged 18-32 years performed an all-out 30-second sprint on a cycle ergometer. Univariate linear regression analysis was employed to evaluate age-, BMI-, performance- and metabolic-dependent changes from pre-exercise to peak GH and integrated GH for 60 min after the sprint.


RESULTS
GH was elevated following the sprint (change in GH: 17.0 +/- 14.2 microg l(-1); integrated GH: 662 +/- 582 min microg l(-1)). Performance characteristics, the metabolic response to exercise and BMI were not significant predictors of the GH response to exercise. However, age emerged as a significant predictor of both integrated GH (beta = -0.547, p = 0.003) and change in GH (beta = -0.448, p = 0.019) after the sprint.


CONCLUSIONS
In non-obese young men, age is a more important predictor of GH following sprint exercise than BMI, sprint performance or the metabolic response to sprint exercise.
Stokes
Keith
K
Sport and Exercise Science Group, School for Health, University of Bath, Bath, UK. k.stokes@bath.ac.uk
Nevill
Mary
M
Hall
George
G
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001823:Body Composition; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D019382:Human Growth Hormone / Q000378:metabolism*; D006801:Humans; D008297:Male
D019382:Human Growth Hormone