Abstract
The loss of the ability to cycle after disease onset, the so-called “bicycle sign”, has been proposed as a new red flag for atypical parkinsonism. However, actual environments or situations for bicycling differ from one country to another, raising the question of whether “bicycle sign” could be universally applicable. The present study suggested that “bicycle sign” could contribute to earlier and better differential diagnosis of parkinsonism in a hilly country like Japan.