Exercise intensity and glycaemic control : the role of redox status and redox-sensitive protein kinase signalling in humans

Physical inactivity and obesity are associated with elevated systemic oxidative stress and the activation of JNK, p38 MAPK, NF-κB, and protein kinase C (PKC) signalling pathways in skeletal muscle. Sustained activation of these stress and mitogen activated protein kinase (SAPK) pathways are associated with impaired glycaemic control, and the development and progression of cardiometabolic disease. Paradoxically, acute exercise also increases oxidative stress and SAPK signalling, yet glycaemic control and skeletal muscle function are enhanced. Research now supports a role for the transient induction of oxidative stress and associated activation of SAPK signalling in the physiological response and adaptation to acute exercise and exercise training. High-intensity interval exercise (HIIE) is a potent exercise stimulus for the improvement of metabolic health and skeletal muscle adaption, however the effect of HIIE on oxidative stress and SAPK signalling is unclear. The aims of this thesis were to explore the effect of HIIE on glycaemic control, exercise-induced oxidative stress, and skeletal muscle SAPK signalling, in a series of independent but related studies.