In the fall of 2015, under contract with the Bicycle Product Suppliers Association (BPSA), with counsel from a field of recreation management experts, and through a review of existing studies of erosional impacts from trail users, the International Mountain Bicycling Association (IMBA) conducted a scientifically controlled field study designed to measure relative levels of soil displacement and erosion resulting from traditional mountain bicycles, electric mountain bicycles (eMTBs), and traditional off-road motorcycles (i.e. dirt bikes). The observations were compiled in controlled environmental conditions, with each type of bike making multiple passes on separated sections of the same trail within a single test site.