The United States http://imagefapbeta.in.net/ www.imagefab.com  The study, led by Dr Josephine Booth, from Dundee, and Prof John Reilly, from Strathclyde, said that increasing activity levels among boys and girls to a recommended hour “would translate to predicted increases of academic attainment of almost one GCSE grade (eg. an increase from a grade C in English to a grade B)”.