Intestinal permeability responses to maximal and submaximal exercise in individuals with normal-weight obesity: an...

Intestinal permeability may contribute to low-grade inflammation and cardiovascular disease (CVD). Despite health benefits, aerobic exercise acutely increases intestinal permeability in healthy populations. Whether at-risk groups display exaggerated intestinal permeability and inflammatory responses to exercise versus healthy individuals is unknown. Individuals with a normal body mass index (BMI) and high body fat percent (normal-weight obesity; NWO) are at increased CVD risk. Inflammation is one suggested mechanism promoting risk in NWO; yet drivers remain unclear. Here, we explored gut permeability and inflammatory biomarkers in NWO (33 ± 7 yr; 55% males) pre/post maximal and submaximal exercise (cycle ergometer) vs. normal-weight lean (NWL; normal BMI, low body fat; 33 ± 7 yr; 50% males) and obese BMI, high body fat (OB; 39 ± 10; 30% males) participants (N = 31; n = 10-11/group). Each participant completed a peak oxygen consumption ([Formula: see text]) test (T1) and 45 min at 65% [Formula: see text] (T2). Full sample and within-group changes postexercise were assessed (paired t tests) and absolute change scores across groups compared (one-way ANOVAs). Following T1, sCD14 increased in the full sample, NWL, and OB (Ps ≤ 0.05). T1 fatty-acid binding protein 2 (FABP2) increased in NWO (P < 0.05). At T2, FABP2 increased in the full sample and OB (Ps ≤ 0.05). T2 also increased IL-6 in all participants, NWL, NWO (Ps ≤ 0.05), and nearly OB (P = 0.06). The absolute changes across groups were similar for all biomarkers at T1 and T2. Body fat percent was moderately correlated with T1 ΔsCD14 in the full sample (r = 0.36; P < 0.05). Overall, NWO's gut barrier response to exercise was largely similar to other groups, with some preliminary exceptions. The influence of relative adiposity on exercise-induced intestinal permeability warrants further examination.NEW & NOTEWORTHY This work is the first to characterize the gastrointestinal response to exercise in NWO and traditional obesity. In addition, we are the first, to our knowledge, to identify a relationship between adiposity and exercise-induced intestinal permeability.