The aim of the present study was to understand if sport improves attention symptoms, social competency, and cognitive functions in children with attention deficit and hyperactivity disorder (ADHD). The present study was designed as a 6-week, prospective trial, including 12 sessions of education/sports therapy. 13 ADHD children participated in a 90-min athletic activity (sports-cADHD) twice a week, while 15 ADHD children received education on behavior control (edu-cADHD). During the 6-week treatment period, the sports-cADHD group showed greater improvements in DuPaul's ADHD Rating Scale scores, parent and teacher version (K-ARS-PT), compared to those of the edu-sADHD group. The cognitive functions assessed with the digit symbol and Trail-Making Test part B (TMT B) were improved in the sports-cADHD group, while the cognitive functions observed in the edu-sADHD group were not significantly changed. The cooperativeness scores in the sports-cADHD group were greatly increased compared to those of the edu-sADHD group. The results demonstrated a positive correlation with sports and improvement in attention symptoms, cognitive symptoms and social skills. The results of the present study suggest that therapy in the form of athletic activity may increase social competency in children with ADHD, as demonstrated by improved cognitive functions.

Stretchable energy storage devices are of great interest because of their potential applications in body-friendly, skin-like, wearable devices. However, stretchable batteries are very challenging to fabricate. The electrodes must have a degree of stretchability because the active materials occupy most of the volume, and the separator and packaging should also be stretchable. Here, an all-component stretchable lithium-ion battery was realized by leveraging the structural stretchability of re-entrant micro-honeycomb graphene−carbon nanotube (CNT)/active material composite electrodes and a physically cross-linked gel electrolyte, without using an inactive elastomeric substrate or matrix. Active materials interconnected via the entangled CNT and graphene sheets provided a mechanically stable porous network framework, and the inwardly protruding framework in the re-entrant honeycomb structure allowed for structural stretching during deformation. The composite network consisting solely of binder-free, highly conductive materials provided superior electron transfer, and vertically aligned microchannels enabled facile ion transport. Additionally, the physically cross-linked gel electrolyte increased the mechanical stability upon deformation of the electrodes and was effective as a stretchable separator. The resulting stretchable battery showed a high areal capacity of 5.05 mAh•cm −2 , superior electrochemical performance up to 50% strain under repeated (up to 500) stretch−release cycles, and long-term stability of 95.7% after 100 cycles in air conditions.

Stretchable energy storage systems are essential for the realization of implantable and epidermal electronics. However, high-performance stretchable supercapacitors have received less attention because currently available processing techniques and material structures are too limited to overcome the trade-off relationship among electrical conductivity, ion-accessible surface area, and stretchability of electrodes. Herein, we introduce novel 2D reentrant cellular structures of porous graphene/CNT networks for omnidirectionally stretchable supercapacitor electrodes. Reentrant structures, with inwardly protruded frameworks in porous networks, were fabricated by the radial compression of vertically aligned honeycomb-like rGO/CNT networks, which were prepared by a directional crystallization method. Unlike typical porous graphene structures, the reentrant structure provided structure-assisted stretchability, such as accordion and origami structures, to otherwise unstretchable materials. The 2D reentrant structures of graphene/CNT networks maintained excellent electrical conductivities under biaxial stretching conditions and showed a slightly negative or near-zero Poisson's ratio over a wide strain range because of their structural uniqueness. For practical applications, we fabricated all-solid-state supercapacitors based on 2D auxetic structures. A radial compression process up to 1/10 densified the electrode, significantly increasing the areal and volumetric capacitances of the electrodes. Additionally, vertically aligned graphene/CNT networks provided a plentiful surface area and induced sufficient ion transport pathways for the electrodes. Therefore, they exhibited high gravimetric and areal capacitance values of 152.4 F g and 2.9 F cm, respectively, and had an excellent retention ratio of 88% under a biaxial strain of 100%. Auxetic cellular and vertically aligned structures provide a new strategy for the preparation of robust platforms for stretchable energy storage electrodes.