The purpose of this study was to determine if pre-exercise glucose ingestion would improve distance swimming performance. Additionally, pre-exercise glucose was provided at 2 different feeding intervals to investigate the affects of the timing of administration. Ten male triathletes ($\overline{\text{X}}\pm SD$: age, 29.5 ± 5.0 years; V̇O_2peak, 48.8 ± 3.2 ml · kg’¹ · min’) swam 4000 m on 3 occasions following the consumption of either a 10% glucose solution 5 min prior to exercise (G⁵), a 10% glucose solution 35 min prior to exercise (G³⁵), or a similar volume of placebo (PL). Despite a significant difference (p < ,01) in blood glucose concentration prior to exercise ($\overline{\text{X}}\pm SD$ in mmol · L ’: G" 8.4 ± 1.1 vs. G⁵ 5.2 ± 0.5 or PL 5.3 ± 0.4), no significant differences were observed in total time ($\overline{\text{X}}\pm SD$ in minutes: G* 70.7 ± 7.6, G^s 70.1 ± 7.6. PL 71.9 ± 8.4). post-exercise blood glucose ($\overline{\text{X}}\pm SD$ inmmol · L⁻¹: G³⁵ 5.1 ± 1.1, G⁵ 5.1 ± 0.9, PL 5.3 ± 0.4), and average heart rate ($\overline{\text{X}}\pm SD$ in bpnv.G" 155.8±10.8, G⁵ 153.6±12.6. PL 152.0± 12.5; p > .05). While not reaching statistical significance, glucose feedings did result in improved individual performance times, ranging from 24 s to 5 min in 8 of the 10 subjects compared to the placebo. These results were found despite significant differences in blood glucose between trials immediately prior to exercise.