<prompt> In a child with exercise induced asthma, which is done ?Prophylaxis with steroidsProphylaxis with mast cell stabilizersProphylaxis with theophylineBreathing excercise  <response>: Exercise induced asthma occurs in genetially susceptible indivduals with hyperactive airways because of loss of water and heat from the respiratory tract following exercise.Water loss induces mucosal hyperosmolarity and stimulates mediator release from mast cells. Ref : Essential paediatrics,O.P.Ghai,7 th edition pg no:359,361 