The influence of carbohydrate (1 l/h of a 6% carbohydrate beverage), gender
, and age on pro- and anti-inflammatory plasma cytokine and hormone changes
was studied in 98 runners for 1.5 h after two competitive marathon races.
The marathoner runners were randomly assigned to carbohydrate (C, n = 48) a
nd placebo (P, n = 50) groups, with beverages administered during the races
in a double-blind fashion using color codes. Plasma glucose was higher and
cortisol was lower in the C than in the P group after the race (P < 0.001)
. For all subjects combined, plasma levels of interleukin (IL)-10, IL-1 rec
eptor antagonist (IL-1ra), IL-6, and IL-8 rose significantly immediately af
ter the race and remained above prerace levels 1.5 h later. The pattern of
change in all cytokines did not differ significantly between the 12 women a
nd 86 men in the study and the 23 subjects <greater than or equal to>50 yr
of age and the 75 subjects <50 yr of age. The pattern of change in IL-10, I
L-1ra, and IL-8, but not IL-6, differed significantly between the C and the
P group, with higher postrace values measured for IL-10 (109% higher) and
IL-1ra (212%) in the P group and for IL-8 (42%) in the C group. In conclusi
on, plasma levels of IL-10, IL-1ra, IL-6, and IL-8 rose strongly in runners
after a competitive marathon, and this was not influenced by age or gender
. Carbohydrate ingestion, however, had a major effect in attenuating increa
ses in cortisol and two anti-inflammatory cytokines, IL-10 and IL-1ra.