title: Different effects of strenuous eccentric exercise on the accumulation of neutrophils in muscle in women and men.
abstract: The purpose of this study was to evaluate the sex differences in delayed onset muscle soreness (DOMS), torque, and accumulation of technetium-99m (Tc-99m) neutrophils in eccentric-exercised muscle. A group of 10 female and 12 male subjects took part in this study. The subjects completed a pre-test using the descriptor differential scale (DDS) to describe DOMS, and tests of concentric and eccentric torque of the right quadriceps. A volume of 100 ml of blood was taken by venipuncture for neutrophil labelling in the early morning of the exercise day. The Tc-99m neutrophils were re-infused intravenously before the eccentric exercise. The exercise stimulus consisted of 300 eccentric repetitions of the right quadriceps muscles. Radionuclide images of both quadriceps muscles (lateral views) were taken at 2 and 4 h. The DDS, and concentric and eccentric torques of the quadriceps were subsequently evaluated at 0 h, 2, 4, 20 and 24 h post-exercise. The presence of Tc-99m neutrophils was greater in the exercised leg than the non-exercised leg at 2 and 4 h post-exercise (P </= 0.013) and greater in the exercised leg of the women compared to the men at 2 h (P = 0.03). The DOMS had increased post-exercise (P < 0.001) and torque had decreased post-exercise (P </= 0.002) but the patterns were different between the sexes. We concluded that the sex influences the presence of Tc-99m neutrophils in the exercised muscle following eccentric exercise. In addition, different patterns of DOMS and torque were observed between the sexes after eccentric exercise, and require further investigation.
authors.affiliation: School of Rehabilitation Sciences, University of British Columbia, T325 2211 Wesbrook Mall, Vancouver, BC V6T 2B5, Canada. macintyr@rehab.ubc.ca
authors.forename: D L
authors.initials: DL
authors.lastname: MacIntyre
authors.forename: W D
authors.initials: WD
authors.lastname: Reid
authors.forename: D M
authors.initials: DM
authors.lastname: Lyster
authors.forename: D C
authors.initials: DC
authors.lastname: McKenzie
mesh_terms: D000328:Adult; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D007866:Leg; D008297:Male; D018482:Muscle, Skeletal / Q000166:cytology / Q000503:physiopathology; D009504:Neutrophils / Q000166:cytology* / Q000502:physiology; D010146:Pain / Q000503:physiopathology; D011930:Reaction Time; D012727:Sex Characteristics; D013667:Technetium / Q000493:pharmacokinetics; D019415:Torque
chemical_list: D013667:Technetium