Celebrating its 15th year in the city, the Airtel Delhi Half Marathon was flagged off by Union Minister for Sports, Kiren Rijiju on Sunday from Jawaharlal Nehru Stadium.Following a countdown, Rijiju fired a pistol in the air to begin the run.The number of registrations for all categories in the 15th edition of the Airtel Delhi Half Marathon (ADHM) has soared to an all-time high of 40,633 participants, organisers said.The Great Delhi Run has registered an unprecedented 16,962 runners while the half marathon witnessed a spike of 11 per cent with 13,115 participants.The 10k run registrations witnessed a jump of 77 per cent to 8,553. The senior citizen run received 1430 registrations, while the champions with a disability will have 573 inspiring individuals defying all odds to complete the distance.The IAAF Gold Label race has prize money of USD 275,000.In the Indian elite line-up, the 2014 and 2011 winner, Suresh Kumar Patel, will lead the men's line-up. In his most recent appearance for