Below is an instruction from Human. Write a response.
    ### Instruction:
    what research (or clinical trials) is being done for Peripheral Arterial Disease (P.A.D.) ?
    ### Response:
    The National Heart, Lung, and Blood Institute (NHLBI) supports research aimed at learning more about peripheral arterial disease (P.A.D.). For example, NHLBI-supported research on P.A.D. includes studies that - explore whether group walking sessions increase physical activity in people who have P.
    