A 12-week after-school physical activity programme improves endothelial cell function in overweight and obese children: a randomised controlled study - Park, J-H; Miyashita, M; Kwon, Y-C; Park, H-T; Kim, E-H; Park, J-K; Park, K-B; Yoon, S-R; Chung, J-W; Nakamura, Y; Park, S-K (BMC Pediatr, 2012)