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Childhood growth-restriction can lead to lasting developmental changes, increasing susceptibility to chronic diseases and neurodegenerative conditions in adulthood. High-intensity interval training (HIIT) elevates brain-derived neurotrophic factor (Bdnf) levels more effectively than moderate intensity continuous exercise, supporting neuroplasticity. Building on these findings, this study aimed to determine whether HIIT could enhance neuroplasticity-related protein expression in the brains of PNGR mice. FVB mouse pups born to normal-protein and low-protein-fed dams were cross-fostered at postnatal day (PN) 1 to establish two groups: postnatally growth-restricted mice (PNGR) and control mice (CON). At PN 21, all pups were weaned onto a normal protein diet and assigned to either a high-intensity interval training group (TRD) or a sedentary group (SED). At PN 45, a maximal exercise performance test was conducted to determine HIIT intensities. Based on these results, mice performed treadmill HIIT 5 days per week for 4 weeks, with alternating intervals of 8 minutes at 85% and 2 minutes at 50% of maximal exercise capacity, totaling 60 minutes per session. At PN 73, all mice were euthanized, and cerebrum tissue was collected for western blot analysis of Bdnf, Tropomyosin receptor kinase B (TrkB), Growth-associated protein 43 (Gap-43), and synaptophysin protein expression. Despite significant body mass reductions observed in both CON and PNGR groups following HIIT, neuroplasticity-related protein expression did not increase in PNGR mice. The PNGR group exhibited consistently lower TrkB and reduced Bdnf and Gap-43 levels compared to CON mice, indicating a limited neuroplastic response to exercise. Contrary to expectations, HIIT did not elevate neuroplasticity markers in PNGR mice, highlighting the lasting impact of early-life growth restriction on brain plasticity and suggesting the need for alternative interventions. Show less

The effects of different exercise intensities on cognitive outcomes and brain-derived neurotrophic factor (BDNF) concentrations in adolescents with overweight/obesity are not yet fully elucidated. This study aimed: (a) to compare the prevalence of responders to cognitive function and BDNF concentration in adolescents with overweight/obesity participating in a 12-week intervention with high-intensity interval training (HIIT) or moderate-intensity continuous training (MICT), and (b) to analyze whether cardiorespiratory fitness (CRF) can explain differences in inter-individual variability between responders and non-responders. Adolescents with overweight/obesity were assigned to HIIT (n = 15), MICT (n = 14), or CG (n = 24). Anthropometrics, body composition, CRF, basal BDNF, and cognitive performance (Trial Making Test (TMT) and Stroop Test (ST)) were evaluated pre- and post-intervention. Training was performed on stationary bikes (3×/week for 12 weeks). The prevalence of responders in ST and TMT was higher in the HIIT group than in CG (93-62%, p = 0.029; 67-33%, p = 0.043), with no differences in MICT. No group differences were found for BDNF responders (HIIT:73%-MICT:71%-CG:46%, p = 0.263). ST and TMT responders had greater CRF improvements than non-responders. HIIT elicited a higher prevalence of cognitive responders than CG. CRF improvements may partially explain individual variability in responsiveness to cognitive outcomes. This is the first study to examine and compare inter-individual variability in cognitive function and BDNF levels following MICT and HIIT interventions in adolescents with overweight/obesity; Exercise intensity and improvements in cardiorespiratory fitness are key factors for optimizing the cognitive effects of interventions in youth with overweight; Twelve weeks of supervised HIIT and MICT training led to increased rates of cognitive responders among adolescents with overweight/obesity. Show less

Attention-deficit/hyperactivity disorder (ADHD) is a common neurodevelopmental condition marked by inattention, hyperactivity, and impulsivity. This narrative review examines the effects of various exercise modalities on ADHD symptoms, based on recent meta-analyses and randomized controlled trials with a focus on children and adolescents published between 2015 and 2025. Exercise modalities categorized as aerobic, open-skill, closed-skill, high-intensity interval training (HIIT), and cognitively demanding activities were examined in recent meta-analyses and clinical trials. Closed-skill exercises like swimming and yoga reduced hyperactivity and impulsivity, while open-skill sports improved attention. HIIT and cognitively engaging tasks enhanced executive function and increased neurochemicals such as BDNF and catecholamines. HIIT shows promise when intensity is individualized and recovery is adequate. Preliminary mechanistic links include catecholamine and BDNF modulation; PI3K-pathways remain hypothesis-generating. Although optimal exercise parameters remain to be determined, accumulating evidence supports the role of structured physical activity as a feasible and effective adjunct to conventional treatment. While many programs involved ~2-3 sessions/week for ≥30 min, heterogeneity in protocols and study quality precludes universal prescriptions. Future trials should report adherence, ADHD-specific outcomes, and risk-of-bias controls. Show less