Ageing is increasing at an alarming rate. Subsequently morbidities in the elderly account for a tremendous proportion of government health budgets. Ageing is associated with a sub-clinical elevation in inflammatory markers termed inflamm-ageing. The majority of chronic diseases in the elderly have an inflammatory component to them and most are driven by increased inflammation. The requirement for interventions to improve health outcomes and reduce inflammation in the elderly are desperately needed. Inflamm-ageing is driven by increased obesity (adiposity), immune-senescence and physical inactivity. Physical activity represents a cheap and easy to implement method of reducing systemic inflammation in the elderly, however after the age of 40 years there is a sharp decline in time spent doing physical activity. The major reasoning behind this is a lack of free time and unwillingness to waste it. Recent paradigms in exercise prescription have shown that high intensity interval training (HIIT), which consists of ~20min exercise per week compared to guidelines of 150mins/week, can elicit similar metabolic and cardiovascular improvements as typical endurance training. To date no study has assessed the effects of HIIT in the elderly. We have conducted a preliminary assessment of inflammation and immunity in younger (20-60yo) participants and shown dramatic improvements. It is therefore conceivable and the purpose of this project to investigate the impact of HIIT in elderly healthy and unhealthy individuals.