title: Change in the capability of reactive oxygen species production by neutrophils following weight reduction in female judoists.
abstract: OBJECTIVE
  Athletes undergoing weight reduction are recognised as being more prone to infection. Few studies exist for athletes on the weight reduction-mediated changes in neutrophil function and related activities such as reactive oxygen species (ROS) production capability, phagocytic activity (PA) and serum opsonic activity (SOA).
  
  
  METHODS
  16 Japanese female university judoists were examined in the early morning of the first day (pre-values) and the last day (post-values) of a 20-day pre-competition training period. Of the 16 subjects, 8 needed to reduce weight (WR group) and the other 8 did not (control group). The parameters assessed were the neutrophil count, serum immunoglobulins and complements, myogenic enzymes, ROS production capability, PA and SOA.
  
  
  RESULTS
  Comparing the post-values with the pre-values, ROS production significantly increased in both groups (p<0.01 for both). PA significantly decreased in the WR group (p<0.05); it also decreased in the control group but the decrease was not significant. SOA significantly increased in the control group (p<0.05), but showed no significant change in the WR group.
  
  
  CONCLUSIONS
  The changes in the WR group were probably a direct consequence of the weight-reduction regimen coupled with the exercise regimen, suggesting that neutrophil parameters (ROS production, PA and SOA) had tended to deviate from their typical compensatory changes to maintain immune system homoeostasis.
authors.affiliation: Department of Social Medicine, Hirosaki University School of Medicine, Zaifu-cho, Hirosaki, Aomori, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Yaegaki
authors.forename: Takashi
authors.initials: T
authors.lastname: Umeda
authors.forename: Ippei
authors.initials: I
authors.lastname: Takahashi
authors.forename: Masashi
authors.initials: M
authors.lastname: Matsuzaka
authors.forename: Norio
authors.initials: N
authors.lastname: Sugawara
authors.forename: Sen
authors.initials: S
authors.lastname: Shimaya
authors.forename: Masaru
authors.initials: M
authors.lastname: Tanabe
authors.forename: Arata
authors.initials: A
authors.lastname: Kojima
authors.forename: Noriko
authors.initials: N
authors.lastname: Mochida
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Nakaji
mesh_terms: D003163:Competitive Behavior / Q000502:physiology; D005260:Female; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D007136:Immunoglobulins / Q000097:blood; D007564:Japan; D016139:Martial Arts / Q000502:physiology*; D009504:Neutrophils / Q000378:metabolism*; D009895:Opsonin Proteins / Q000097:blood; D010587:Phagocytosis / Q000502:physiology; D017382:Reactive Oxygen Species / Q000378:metabolism*; D015431:Weight Loss / Q000502:physiology*
chemical_list: D007136:Immunoglobulins; D009895:Opsonin Proteins; D017382:Reactive Oxygen Species