The effects of tobacco smoking and exercise on cerebro-vascular responses and systemic inflammation: the influence of smoking status and history

Tobacco use is significant contributor to preventable mortality accounting for 15% of all deaths within Australia and despite the well-known risk posed by tobacco smoking, 12% of the population are daily smokers. Tobacco smoking affects multiple organ systems and ultimately increases the risk of cardiovascular disease, cancers, chronic obstructive pulmonary disease, diabetes, autoimmune disease and neurodegenerative diseases. Some of the most notable health consequences from smoking arise from changes to the immune system and inflammatory process, however it has been suggested that microcirculation, hemodynamics and autonomic regulation may play crucial roles in the development of smoking associated disease states.Contrary to the development of smoke-induced pathological states, regular exercise protects against all-cause mortality and is reported to improve respiratory, immune, inflammatory and hematological parameters. Even a single bout of exercise is suggested to induce an immune-inflammatory influx resulting in the creation of an anti-inflammatory environment, additionally, acute exercise exerts favourable outcomes on autonomic function and cerebral microcirculation. Given that disease development is often associated with long-term smoking, it is important to determine the outcomes to both smoking and exercise in those with shorter and longer smoking histories respectively. Further, the outcomes of pre-exercise smoke exposure these populations remain elusive, as it is unknown whether smoking may compromise the acute exercise response and thus impede any beneficial effects in smoking populations. Therefore, the aims of this thesis were two-fold; firstly, to examine the effect of smoking status (ie. smoker v non-smoker) on the acute immune-inflammatory, autonomic and cerebral oxygenation responses to acute smoking and exercise. A second aim was to examine the effect of age, and therefore smoking history (ie. younger v middle-aged smokers) on the aforementioned responses.