The Effect of a Repetitive Feeding Challenge With Carbohydrate Versus Fat on Markers of Gastrointestinal Integrity and Systemic Outcomes in Response to Endurance Exercise.
Isabel G Martinez, Jessica R Biesiekierski, Christopher E Rauch et al.
✦ AI-curated · Sources linked
In 30 seconds
This randomized controlled trial examined whether a 7-day repetitive feeding challenge with fat, compared with carbohydrate (CHO), affected gastrointestinal integrity and systemic inflammatory markers during endurance exercise. Thirty-six endurance athletes completed a 2-hour run and self-paced distance test before and after the intervention. Exercise-related I-FABP and sCD14 responses were similar within and between groups. CRP decreased in the CHO group (0.327 ± 0.449 vs. 0.062 ± 0.231 μg/ml, p = .030), but not significantly in the fat group. The authors concluded that fat did not increase the measured markers compared with CHO.
Key findings
- I-FABP responses did not differ significantly between groups at T1 (p = .404) or T2 (p = .440).
- sCD14 responses did not differ significantly between groups at T1 (p = .888) or T2 (p = .149).
- CRP decreased in the CHO group (0.327 ± 0.449 vs. 0.062 ± 0.231 μg/ml, p = .030), but not in the fat group (p = .351).
- Total gastrointestinal symptom severity was not correlated with I-FABP, sCD14, or CRP.
Why it matters
The findings address whether repeated fat intake during exercise training is accompanied by evidence of gastrointestinal injury, bacterial endotoxin translocation, or systemic inflammation. In this trial, the measured markers did not indicate greater disruption with fat than with CHO, while symptom severity did not track with these biomarkers. This helps distinguish reported gastrointestinal symptoms from the specific biological outcomes assessed.
What to keep in mind
The study assessed biomarker responses around a defined endurance-exercise challenge and a 7-day feeding protocol; the abstract does not report longer-term outcomes.