Cross adaptation is the process of inducing physiological adaptation utilising one environmental stressor (e.g. heat) prior to exposure in another environmental stressor (e.g. hypoxia) resulting in attenuated disruption to homeostasis relative to the unadapted state. Further to this, data has begun to examine the impact of combined stressors e.g. heat and hypoxia, on adaptation. Cross-, and combined adaptation between environmental stressors may be induced at rest, or during exercise in both terrestrial environments (as a cross acclimatisation model) as well as artificial environments (e.g. a cross acclimation model). Irrespective of the method induction, the underpinning adaptations are derived from cellular and molecular pathways with adaptations at this level being described as “Cross Tolerance”. This presentation will outline our current understanding of mechanisms and applications pertaining to cross-, and combined adaptation and the relevant pathways of cross tolerance, in exercise and health physiology.