Background: Horse racing is a weight category sport in which jockeys must chronically maintain a low body mass to compete, over a protracted season. The need to relentlessly align body mass with racing limits appears to encourage the use of short-term and potentially dangerous acute weight loss strategies. The purpose of this study was to investigate and assess the dietary habits of Irish Jockeys using established methods as well as incorporating novel sensing technologies. Methods: The primary aim was achieved through two separate but related studies. Study one: Dietary intake was assessed in 18 professional Irish Jockeys (11 Flat and 7 National Hunt) over a typical racing week, using a standard 7-day food diary. Study Two: There are limitations associated with the traditional methods of dietary assessment therefore a new innovative method of dietary assessment using novel sensing technologies, the Microsoft SenseCam, a wearable camera, was evaluated. The SenseCam was worn by 17 trainee jockeys in tandem with keeping a standard 1-day food diary to increase the accuracy of the dietary assessment. For the purposes of comparison, the study was then broadened to two further populations, elite Gaelic footballers and a group of healthy active University Students to evaluate potential differences across populations. Results: In study one the dietary analysis showed mean daily energy intake (1803±564 kcal) was low in both Flat and National Hunt groups alike and appeared to provide insufficient availability of energy for sustainment of usual daily and metabolic processes. Carbohydrate intake (3.7 ±1.3g.kg-1) was below recommendations for athletes, whilst protein levels (1.3 ± 0.5. kg-1) were within recommended amounts for athletes. In general the levels fell short of the recommendations for athletes partaking in weight category sports. Jockeys consumed well below (0-2) the recommended five daily servings of fruit and vegetables set by the World Health Organization. Study two showed that by using the SenseCam in tandem with the 1-day food diary a more accurate dietary assessment could be gleaned. Mean total calorie intake using the food diary alone compared to the combination of the food diary and SenseCam were 2349±827.9 vs 2631±893.4 kcal, 2600±521.9 vs 3191±770.2 kcal and 2237±318.5 vs 2487±404.6 kcal for the trainee jockeys, Gaelic footballers and University students respectively. This represented a difference of 10.7% (p≤0.001); 17.7% (p≤0.001); and 10.1% (p≤0.01) among measurements methods for trainee jockeys, Gaelic footballers, and university students, respectively. The SenseCam allowed the dietitian to pick up on foods consumed but not documented in the food diary. It also allowed identification of brand types and portions size making the overall dietary assessment more accurate. Conclusions: Results from this research suggest that due to the chronically energy restricted lifestyle associated which Irish professional jockey, this may place them at risk of compromised long term health. By using novel sensing technologies it may be possible to more accurately assess dietary intake in this population, in order to assist in the education and provision of more accurate dietary advice in the future.