RT Journal Article SR Electronic T1 Change in the capability of reactive oxygen species production by neutrophils following weight reduction in female judoists JF British Journal of Sports Medicine JO Br J Sports Med FD BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine SP 322 OP 327 DO 10.1136/bjsm.2006.032029 VO 41 IS 5 A1 Makoto Yaegaki A1 Takashi Umeda A1 Ippei Takahashi A1 Masashi Matsuzaka A1 Norio Sugawara A1 Sen Shimaya A1 Masaru Tanabe A1 Arata Kojima A1 Noriko Mochida A1 Yousuke Yamamoto A1 Shigeyuki Nakaji YR 2007 UL http://bjsm.bmj.com/content/41/5/322.abstract AB 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.