= 24) reported to the laboratory in an overnight fasted state at 8:00 am on two occasions separated by at least two weeks. After providing a blood sample at 8:00 am, subjects ingested 0.5 liters flavored water alone or 0.5 liters water with 7 kcal kg−1
chia seed oil (random order), provided another blood sample at 8:30 am, and then started running to exhaustion (~70% VO2max
). Additional blood samples were collected immediately post- and 1-h post-exercise. Despite elevations in plasma alpha-linolenic acid (ALA) during the chia seed oil (337%) versus
water trial (35%) (70.8 ± 8.6, 20.3 ± 1.8 μg mL−1
, respectively, p
< 0.001), run time to exhaustion did not differ between trials (1.86 ± 0.10, 1.91 ± 0.13 h, p
= 0.577, respectively). No trial differences were found for respiratory exchange ratio (RER) (0.92 ± 0.01), oxygen consumption, ventilation, ratings of perceived exertion (RPE), and plasma glucose and blood lactate. Significant post-run increases were measured for total leukocyte counts, plasma cortisol, and plasma cytokines (Interleukin-6
(IL-10), and Tumor necrosis factors-α (TNF-α)), with no trial differences. Chia seed oil supplementation compared to water alone in overnight fasted runners before and during prolonged, intensive running caused an elevation in plasma ALA, but did not enhance run time to exhaustion, alter RER, or counter elevations in cortisol and inflammatory outcome measures.