Influence of carbohydrate on cytokine and phagocytic responses to 2 h of rowing.

PURPOSE: This study examined the influence of carbohydrate (C) versus placebo (P) beverage ingestion on the phagocytic and cytokine responses to normal rowing training by 15 elite female rowers. METHODS: Athletes received C or P before, during and after, two, 2-h bouts of rowing performed on consecutive days. Blood was collected before and 5-10 min and 1.5 h after rowing. Metabolic measures indicated that training was performed at moderate intensities, with some high-intensity intervals interspersed throughout the sessions. RESULTS: Concentrations of blood neutrophils and monocytes, phagocytic activity, and plasma IL-1ra were significantly lower postexercise after C versus P ingestion. No differences were observed for oxidative burst activity, IL-6, IL-8, or TNFalpha. Glucose was significantly higher after 2 h of rowing with C ingestion; however, cortisol, growth hormone, epinephrine, norepinephrine, and CRP were not affected by carbohydrate. CONCLUSIONS: These data indicate that carbohydrate compared with placebo ingestion attenuated the moderate rise in blood neutrophils, monocytes, phagocytosis, and plasma IL-1ra concentrations that followed 2-h bouts of training in elite female rowers. No changes in blood hormone concentrations were found.

Immune function in female elite rowers and non-athletes.

OBJECTIVE: To compare immune function in female rowers and controls in the resting state, and then correlate the results with a two month history of upper respiratory tract infection (URTI). METHODS: Subjects included 20 elite female rowers located at the ARCO Olympic Training Centre in Chula Vista, California, and 19 non-athletic female controls. These two groups were compared cross sectionally for immune function and infection rates. RESULTS: Granulocyte/monocyte phagocytosis, oxidative burst activity, and plasma cytokine concentrations (interleukin-6, tumour necrosis factor-alpha, and interleukin-1 receptor antagonist) did not differ significantly between groups. Phytohaemagglutinin induced lymphocyte proliferative response (adjusted whole blood method) was significantly higher (31% and 36% for optimal and suboptimal concentrations respectively) in rowers than in controls. Natural killer cell activity was substantially higher (1.6-fold for total lytic units) in the female rowers than in controls. Two month health logs disclosed 5.2 (1.2) and 3.3 (1.1) days with URTI symptoms for the rowers and controls respectively (p = 0.268). For all 39 subjects combined, and for the 20 rowers separately, none of the immune parameters correlated significantly with number of days with URTI symptoms. CONCLUSIONS: In this cross sectional comparison of elite female rowers and non-athletes, a group difference was found for natural killer cell activity and phytohaemagglutinin induced proliferative response (whole blood technique), but not other measures of immune function. The number of days with URTI symptoms during the spring season did not differ between groups, and variations in blood measures of immunity were unrelated to URTI.

Immune response to two hours of rowing in elite female rowers.

The influence of carbohydrate (C) versus placebo (P) beverage consumption on the immune and hormonal responses to normal rowing training sessions was measured in 15 elite female rowers residing at the U.S. Olympic Training Center. In a randomized, counterbalanced design, the athletes received C or P beverages (double-blind) before, during, and after two 2-hour bouts of rowing (one day apart). Blood samples were collected before, and 5-10 minutes and 1.5 hours after rowing. Metabolic measures indicated that training was performed at moderate intensities, with some high intensity intervals interspersed throughout the sessions (mean oxygen uptake of 2,307+/-169 m x min(-1), 57% of VO2max). Glucose and insulin were significantly lower after two hours of rowing with ingestion of P compared to C. The patterns of change in cortisol, growth hormone, epinephrine, and norepinephrine did not differ between C and P rowing trials. Blood neutrophil cell counts and the neutrophililymphocyte ratio were significantly higher following P versus C rowing sessions. The patterns of change in blood lymphocyte and lymphocyte subset counts, and lymphocyte proliferative responses did not differ between P and C trials, except for a slight difference in NK cell counts and activity. In summary, minimal changes in blood hormonal and immune measures were found following two-hour bouts of training in elite female rowers. Carbohydrate compared to placebo ingestion attenuated the moderate rise in blood neutrophil counts, but had slight or no effects on other immune parameters.