Springtime brings a second peak for colds, with erratic temperatures irritating your airwaves and seasonal allergies making many of us more prone to infections. But you don’t have to fall victim to this seasonal assault. Yoga’s holistic sister science, Ayurveda, has long identified spring as a peak time of susceptibility to illness, but it also suggests some simple changes to your lifestyle so that you can bolster your physiology against unwelcome visitors this season.