Glucose tolerance status associates with improvements in cognitive function following high-intensity exercise in adults with obesity

Purpose: Obesity, insulin resistance (IR), and proinflammatory cytokines associate with cognitive decline. Numerous studies document cognitive benefits of acute exercise bouts in lean individuals. However, how comorbidities such as obesity and IR influence cognitive changes induced by acute exercise is unclear. We examined the effects of acute high-intensity aerobic exercise on cognitive function in age-matched and BMI-matched obese adults with normal glucose tolerance (NGT) or impaired glucose tolerance (IGT) and in lean, NGT adults.Methods: 49 adults (15 Lean, 18 Obese-NGT, 16 Obese-IGT) performed one session of high-intensity interval exercise (four cycles of 4-min at 75% W-max with 3-min rest). Cognitive function testing and blood sampling were performed pre-and post-exercise. Results: Following exercise, measurements of executive function and working memory were improved in Lean and Obese-NGT (p < 0.05), but not Obese-IGT. Changes in cognitive function following exercise negatively correlated with 2-hr glucose during an OGTT after controlling for body weight and body composition (r(p) =-0.40, p = 0.007). Serum levels of inflammatory cytokines IL-6 and CRP remained increased 60-minutes post-exercise in Obese-IGT, but not in Lean or Obese-NGT, which positively associated with 2-hr glucose during an OGTT (p < 0.01) and negatively with changes in cognitive function following exercise (p < 0.01). Greater insulin levels in Obese-IGT post-exercise also negatively correlated with changes in cognitive function following exercise (p < 0.01).Conclusion: Improvements in cognition following acute high-intensity exercise positively associate with glucose tolerance, independent of body weight and body composition. Further, poorer changes in cognitive performance following exercise associate with persistent peripheral inflammation.

Automated summary

The study found that acute high-intensity aerobic exercise improves cognitive function in lean and obese with normal glucose tolerance individuals, but not in obese with impaired glucose tolerance individuals. Changes in cognitive function were negatively correlated with glucose levels after OGTT and associated with peripheral inflammation.