Research on children with ADHD has suggested that playing outside in a green area can help to control the condition but a lot of the evidence is anecdotal and there has been little systematic comparison with other activities. Researchers from the University of Illinois took children on three different walks: one in a park, one in a city centre and one in a suburban area. The walks were the same for all the children, none of them were on medication and they all walked with the same adult. At the end of the walks they were given a test - reciting a series of numbers backwards - designed to measure their level of attention. This particular test does not improve with practice and none of the testers knew which child had been on which walk. The walk in the park was found to be more effective than the other walks at improving concentration and its effect was as good as, if not better than, medication.
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