Effects of variation in exercise training load on cognitive performances and neurotrophic biomarkers in patients with coronary artery disease.

PURPOSE:This study compared the effects of linear (LP) and non-linear (NLP) training periodization on resting cognitive functions, neurotrophic biomarkers (brain-derived neurotrophic factor [BDNF], insulin-like growth factor-1 [IGF-1]), and cathepsin-B in patients with coronary artery disease (CAD). METHODS:Forty-four patients with CAD reported to our laboratory on two occasions to undergo testing procedures before and after training sessions, and were then blindly randomized to NLP or LP for 36 training sessions. Visit 1 included blood samples and a maximal cardiopulmonary exercise testing to get maximal oxygen uptake (V̇O2peak). Visit 2 included cognitive functions assessment. RESULTS:Thirty-nine patients completed the study (LP: n=20, NLP: n=19), with no observed changes in cognitive performances after the training intervention in either group. IGF-1 concentration decreased in both groups (time-effect: p<0.001), while BDNF concentration increased (time-effect: p<0.05) without interaction (p=0.17 and p=0.65, respectively), and cathepsin-B did not change after the intervention (p>0.05). Associations were found between ΔV̇O2peak and ΔBDNF (R2=0.18, p=0.04), and ΔIGF-1 and Δ short-term/working memory (R2=0.17, p=0.01) in the pooled sample, with Δ IGF-1 and ΔBDNF accounting for 10% of the variance in Δ short-term/working memory. In the LP group, associations were found between ΔV̇O2peak and ΔBDNF (R2=0.45, p=0.02), ΔBDNF and Δ short-term/working memory (R2=0.62, p=0.004), ΔIGF-1 and Δ short-term/working memory (R2=0.31, p=0.01), and Δ IGF-1 and Δ executive function (R2=0.22, p=0.04). CONCLUSION:This finding highlights the potential importance of monitoring and targeting BDNF and IGF-1 concentration as potential biomarkers for improving short-term and working memory in the population with CAD.