Effect of muscle oxygenation during resistance exercise on anabolic hormone response.
OBJECTIVE
The mechanisms that underlie the affect of acute program variables on muscle growth and strength development for strength/power athletes have been of great interest. This investigation examined the affects of two different resistance exercise protocols on muscle oxygenation, and the anabolic hormonal response to such exercise.


METHODS
Eleven experienced resistance-trained male athletes performed four sets of the squat exercise using either a low-intensity, high-volume (LI; 15 repetitions at 60% one-repetition maximum [1-RM]) or high-intensity, low-volume (HI; 4 repetitions at 90% 1-RM) load. Venous blood samples were obtained before (Pre), immediate (IP), 20- (20P), and 40-min (40P) postexercise. Continuous-wave near-infrared spectroscopy was used to measure oxygen desaturation during exercise.


RESULTS
No differences in muscle deoxygenation were seen between LI and HI. However, time-dependent postexercise reoxygenation was significantly different between the two exercise sessions (35.3 +/- 17.4 s vs 24.5 +/- 14.3 s in LI and HI, respectively). Testosterone and growth hormone (GH) concentrations were significantly elevated from Pre at IP, 20P, and 40P in both LI and HI. GH concentrations were higher (P<0.05) for LI than at HI at 20P and 40P.


CONCLUSIONS
Muscle oxygen recovery kinetics appeared to be influenced by differences in the intensity and volume of exercise, and delayed reoxygenation appears to affect the GH response to exercise.
Hoffman
Jay R
JR
The College of New Jersey, Ewing, NJ 08628, USA. hoffmanj@tcnj.edu
Im
Joohee
J
Rundell
Kenneth W
KW
Kang
Jie
J
Nioka
Shoko
S
Spiering
Barry A
BA
Kime
Ryoto
R
Chance
Britton
B
Speiring
Barry A
BA
D000328:Adult; D015444:Exercise / Q000502:physiology*; D013006:Growth Hormone / Q000097:blood; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010806:Physical Education and Training; D013739:Testosterone / Q000097:blood; D014891:Weight Lifting
D013739:Testosterone; D013006:Growth Hormone; D010100:Oxygen