Acute exercise linearly increased integrated growth hormone concentrations (from 250 at rest to 713 µg/L/min at highest intensity) and production rate (P<0.05) in young men.
RCT (n=10)
Randomly ordered occasions
p-value: p=<0.05
To investigate the effects of exercise intensity on growth hormone (GH) release, 10 male subjects were tested on 6 randomly ordered occasions 1 control condition (C), 5 exercise conditions (Ex). Serum GH concentrations were measured in samples obtained at 10-min intervals between 0700 and 0900 (baseline) and 0900 and 1300 (exercise+ recovery). Integrated GH concentrations (IGHC) were calculated by trapezoidal reconstruction. During Ex subjects exercised for 30 min (0900-0930) at one of the following intensities normalized to the lactate threshold (LT): 25 and 75% of the difference between LT and rest (0.25LT and 0.75LT, respectively), at LT, and at 25 and 75% of the difference between LT and peak (1.25LT and 1.75LT, respectively). No differences were observed among conditions for baseline IGHC. Exercise+recovery IGHC (mean +/- SE: C = 250 +/- 60; 0.25LT = 203 +/- 69; 0.75LT = 448 +/- 125; LT = 452 +/- 119; 1.25LT = 512 +/- 121; 1.75LT = 713 +/- 115 microg x l(-1) x min(-1)) increased linearly with increasing exercise intensity (P < 0.05). Deconvolution analysis revealed that increasing exercise intensity resulted in a linear increase in the mass of GH secreted per pulse and GH production rate production rate increased from 16. 5 +/- 4.5 (C) to 32.1 +/- 5.2 microg x distribution volume(-1) x min(-1) (1.75LT), P < 0.05, with no changes in GH pulse frequency or half-life of elimination. We conclude that the GH secretory response to exercise is related to exercise intensity in a linear dose-response pattern in young men.
Pritzlaff et al. (Sun,) reported a rct. Acute exercise vs. Control condition (rest) was evaluated on Integrated growth hormone concentrations (IGHC) and production rate (p=<0.05). Acute exercise linearly increased integrated growth hormone concentrations (from 250 at rest to 713 µg/L/min at highest intensity) and production rate (P<0.05) in young men.