Brief muscle hypoperfusion/hyperemia: an ergogenic aid?
The purpose of this study was to investigate how short-duration forearm hypoperfusion/hyperemia affects isometric wrist flexion maximal voluntary contraction (MVC) in humans. Fourteen subjects (7 men and 7 women) performed isometric wrist flexion MVC on a Biodex ergometer under 2 experimental conditions: (a) without preceding forearm blood pressure cuff occlusion (control), or (b) immediately following forearm blood pressure cuff occlusion (2 minutes at 200 mm Hg) with 10 seconds of hyperemia (postocclusion). The mean MVC was greater in the postocclusion trial for both men (men, control = 267 +/- 57 J vs. postocclusion = 303 +/- 48 J; p < 0.05) and women (women, control = 185 +/- 21 J vs. postocclusion = 237 +/- 21 J; p < 0.005). The delta MVC between control and postocclusion trials was similarly increased in men and women (men, 36 +/- 13 J vs. women, 52 +/- 11 J; p = not significant [NS] between genders). When men and women were coupled as a single group, the MVC was approximately 20% greater in the postocclusion trial compared with the control trial (control = 226 +/- 31 J vs. postocclusion = 270 +/- 27 J; p < 0.0005). With Doppler/ultrasound imaging, brachial artery flow following 2 minutes of forearm occlusion was five- to sixfold greater than baseline blood flow (p < 0.0005). Isometric wrist flexion MVC is improved in both men and women following brief duration forearm cuff occlusion. The hyperemia that follows cuff occlusion may provide this putative effect.
Libonati
J R
JR
Department of Cardiopulmonary Sciences, Northeastern University, Boston, Massachusetts 02115, USA.
Howell
A K
AK
Incanno
N M
NM
Pettee
K K
KK
Glassberg
H L
HL
D000328:Adult; D001783:Blood Flow Velocity; D001794:Blood Pressure / Q000502:physiology; D001916:Brachial Artery / Q000000981:diagnostic imaging / Q000502:physiology; D005260:Female; D005542:Forearm / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000502:physiology; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D012039:Regional Blood Flow; D015203:Reproducibility of Results; D018608:Ultrasonography, Doppler; D014953:Wrist / Q000000981:diagnostic imaging / Q000502:physiology