ACUTE EFFECTS OF RESISTANCE EXERCISE ON BRAIN-DERIVED NEUROTROPHIC FACTOR IN CHILDREN

https://youtu.be/i6DvFk-gQTo BACKGROUND: Brain-Derived Neurotrophic Factor (BDNF) is a protein classified as a neurotrophin that is known for its positive cognitive effects, brain plasticity, and brain health. Children and adults with obesity and Prader-Willi Syndrome (PWS), a genetic condition for obesity, present lower baseline concentrations of BDNF compared to those who are lean. Acute endurance exercise increases BDNF concentrations in an intensity and duration manner. The purpose of this study was to investigate whether acute resistance exercise increases BDNF blood concentrations and to determine if PWS and/or obesity affect this response. METHODS: 10 children with PWS (10.9 ± 2.7 yrs; 42.9 ± 8.5% body fat), 9 children with non-syndromic obesity (9.4 ± 1.2 yrs; 41.5 ± 4.4% body fat), and 8 children without obesity (9.3 ± 1.4 yrs; 18.4 ± 5.7% body fat) completed a step-up protocol with a weighted vest (6 sets of 10 repetitions on each leg with 1-min rest in between). Blood samples were obtained pre-exercise (PRE), immediately post-exercise (IP), 15 minutes (+15), and 60 minutes (+60) into recovery. RESULTS: The children with PWS (PWS) and non-syndromic obesity (obese) showed a significantly lower BDNF concentration at PRE compared to the children without obesity (lean) (PWS = 17808 ± 3176, obese = 16915 ± 3348, lean = 28874 ± 3551 pg/ml; p = 0.029 for PWS, p = 0.022 for obese). There was no significant increase in BDNF concentrations from exercise in any group. BDNF concentrations at +60 were significantly lower than all other times in PWS (PRE: p = 0.031; IP: p = 0.018; +15: p = 0.027); lower than +15 in obese (p = 0.015); and lower than PRE and IP in lean (PRE: p < 0.001; IP: p = 0.038). There were no significant area under the curve (AUC) differences among the groups. CONCLUSION: As shown before, obesity (syndromic and non-syndromic) was associated with decreased BDNF concentrations at rest. An acute resistance exercise of moderate intensity 12-17 min long did not significantly increase BDNF possibly as the exercise load was not enough to elicit a change or the sample size was not enough to detect an interaction effect. However, since the AUCs were similar between all groups, this suggests that exercise may have a potential effect during recovery from exercise in those with reduced concentrations at baseline.