A well-functioning body's immune system is an indispensable factor for being healthy and efficient. Since the immune system is largely dependent on our habits and lifestyle, we can influence it and strengthen it in a targeted manner. How this is possible through regular exercise with corresponding regeneration, healthy nutrition, effective stress management and restful sleep is explained using scientific findings and concrete examples. With this knowledge, you will be enabled to strengthen your defense system in a targeted manner, to build up protective health factors and, if necessary, to reduce existing risk factors. Make it healthy and fit through all seasons!