2019-02-072019-02-072018https://eresearch.qmu.ac.uk/handle/20.500.12289/9262Background – Nutritional supplementation has become a justified method to aid athletic sports performance. Recent research into micronutrients, minerals and vitamins has revealed appealing effects on sports and exercise performance. Magnesium is a critical mineral found within the body, playing vital roles, which are fundamental to the body at both rest and during exercise. Research has therefore implicated Magnesium as a potential ergogenic aid to sports performance, however the literature is conflicting and involves only top-level male athletes. In addition, individual’s habitual magnesium intake has been highlighted as a probable contributing factor in the minerals potential for improving sports performance. Method – The study was a randomized, cross over, single blind, placebo controlled 22 day repeated measures design. A total of 10 participants were recruited to take part in the current study. Gender was split equally including 5 Males and 5 Females. After completion of a 4-day diet diary, participants completed baseline measurements consisting of a salivary magnesium assay, bioelectrical impedance analysis and a 5km ergometer cycle time trial. On completion of baseline measurements, participants began supplementation in two separate groups receiving either magnesium or placebo in parallel until a cross over after a washout period. Results – Results concluded that Mean cycle time trial scores after magnesium supplementation when compared with baseline were significantly faster (p=0.006). In addition, time trial scores after magnesium were slight but significantly faster over placebo (p=0.023). In relation to BIA analysis, mean phase angle improved amongst subjects showing a 4.4% increase from baseline as well as a 1.6% increase from placebo. Both male and female participants were consuming less than the dailyrecommended 306mg/d 286mg/d respectively. Lastly, statistical analysis showed no significance between groups during salivary magnesium analysis. Conclusion - In sum magnesium supplementation has the potential to improve sports performance in individuals, especially amongst those who have a pre-existing deficiency. However, a combination of confounding factors impact the power and validity of the results therefore no conclusive statements can be made about magnesium’s ability to effect individual’s capacity in sports performance.Thesis