Author(s): MOŠKON MAROLT, S., IHAN, A., STROJNIK, V., TOMAŽIN, K., Institution: UNIVERSITY OF LJUBLJANA, FACULTY OF SPORTS, Country: SLOVENIA, Abstract-ID: 2192

INTRODUCTION:
Brain derived neurotrophic factor (BDNF) is a key mediator of exercise induced neuroplasticity and cognitive enhancement (1). Serum (total measurable) and plasma (freely-circulating) BDNF reflect different physiological sources, yet it is unclear whether resistance loading strategies elicit distinct compartment specific responses. Traditional resistance exercise (TRE) increases BDNF, but whether accentuated eccentric loading provides additional neurotrophic or cognitive benefits remains unknown. Accentuated eccentric exercise (AECC), using supramaximal eccentric loads, imposes greater mechanical tension and neural drive than TRE (2) suggesting it may enhance BDNF signaling and executive functions. This study compared the acute effects of TRE (80% 1RM) and AECC (80% concentric, 110% eccentric) on BDNF and Stroop performance in young adults.
METHODS:
Sixteen healthy, moderately active young male adults completed three protocols in randomized order, at least 7 days apart: control (seated rest), TRE (80% 1RM), and AECC (80% concentric, 110% eccentric). Each exercise session included bench press, leg press, and lat pulldown (4 sets to failure, 2 min rest). Executive functions were assessed using the Stroop test before and 15 min after each protocol. Serum and plasma BDNF were measured at baseline, 5 min, 1 h, and 3 h post protocol using ELISA. Two-way ANOVA and Friedman test with Wilcoxon signed ranks test were performed separately for the Stroop test, serum and plasma BDNF. Statistical significance was set at p<0.05.
RESULTS:
Serum BDNF increased 5 min after TRE (+30%, p < 0.001) and AECC (+34%, p = 0.013), with no change in control. At 1 h post, serum BDNF declined after TRE (-11%, p = 0.012) but remained stable after AECC compared to 5 min post. At 3 h post, serum BDNF was slightly above baseline in both exercise protocols (p > 0.05). Plasma BDNF increased 5 min post TRE (+126%, p < 0.001), AECC (+127%, p < 0.005), and control (p = 0.049). Only TRE and AECC maintained elevated plasma BDNF at 1 h (TRE: +60%, p = 0.010; AECC: +48%, both p = 0.039), while control returned to baseline. Stroop Word and Color performance improved after all protocols (all p < 0.01), with the largest improvements after AECC (Word: +7%, Color: +10%, both p < 0.001). Executive functions (Color-Word) improved only after exercise (TRE: +10%; AECC +9%; p < 0.001), not control.
CONCLUSION:
AECC elicited a more sustained BDNF response than TRE, maintaining elevated serum and plasma concentrations up to 1–3 h post exercise. Executive function improved only after exercise, supporting a link between resistance induced BDNF elevation and cognitive enhancement. These findings suggest that eccentric accentuated loading may optimize acute neurotrophic signaling and highlight the value of assessing both serum and plasma BDNF to capture compartment specific kinetics. Further research should examine whether chronic AECC training yields long term neurocognitive benefits.
[1] Bathina 2015/ [2] Wagle 2017