This prospective study inclues all parkinsonian syndromes who had a follow-up for OAB. They must have a security delay over five minutes, no severe cognitive, motor or psychiatric disorders. We invite them to drink until a need to void (or equivalent). Bladder filling is measured by bladder scan, then they performe gait tests in a specific place, with calm and no passage : Patient can use their habitual walking device. Speed walk asking is comfortable for the two test. Three ten-meter tests, one double-task ten-meter test, one timed-up-and-go test, one timed raise of the floor (GMT). We repeat the same tests after voiding or self-catheterization. Toilets are just next to the hall where they realize the tests. A clinical examination assesses urinary dysfunction (USP, IPSS), motor score (UPDRS-III, Hoehn and Yahr scale, daily equivalent of levodopa), history of falls and comorbidities.