Intake of omega-3 (n-3) polyunsaturated fatty acids (PUFAs) has been identified as potentially beneficial for athletes (Philpott et al., 2019). Based on current evidence, n-3 PUFA supplementation may improve athlete endurance capacity and aid recovery from exercise. In contrast, there is insufficient evidence from studies in athletic populations to support the claim that n-3 PUFA supplementation facilitates muscle growth during resistance training or preserves muscle mass during catabolic scenarios such as energy restriction or immobilisation (Philpott et al., 2019). However, one recent study has shown benefits in an immobilisation model in young active females (McGlory et al 2019), suggesting potential sex differences in muscle responses to omega-3 ingestion. Moreover, the wider effects of ingesting foods rich in n-3 PUFAs, such as seafood products, rather than n-3 PUFA supplementation, on adaptation/recovery from exercise needs further evaluation. Considering that fish offers a protein source rich in essential micronutrients and vitamins in addition to being a unique source of n-3 PUFA (Carboni et al., 2019; de Roos et al, 2017) it could prove beneficial. Current dietary recommendations include the consumption of one (Scotland) or two (UK) portions of fish or seafood per week, of which one should be oily. However, many people do not reach the national recommendation for total fish intake, especially young people. Combined with significant differences in amount of n-3 PUFAs in seafood products (de Roos et al., 2017) there is a need to evaluate the impact of fish intake in a comprehensive manner. The focus on a healthy sustainable diet is of interest to both the general population and those in the sports community, particularly since seafood consumption would align with a food first approach to sport nutrition guidance.
The initial aim of this PhD project is to characterise seafood consumption and supplement use in an athlete cohort (elite to recreational), exploring links to athletic performance and recovery. Beginning with a cross sectional approach, applying in depth dietary and physical assessments, and analysing levels of biochemical and metabolic markers, such as fatty acid composition and vitamin D status within blood, the project will then progress onto a pilot dietary intervention study. The intervention study will examine responses to exercise, alongside n-3 fatty acid incorporation into skeletal muscle cell membranes, in young or older athletes identified to have low omega-3 status. Responses to exercise will assess acute physiological and performance-based metrics such as neuromuscular function, strength, speed, power, and aerobic endurance, but will also aim to establish whether biochemical alterations correlate with improvements in muscle performance over a 12-week study period. The dietary intervention will assess the effect(s) of increased seafood consumption, in contrast to n-3 PUFA supplementation alone, or control group, on adaptations to exercise over the 12-week intervention. This interdisciplinary PhD project will generate key knowledge and skills ranging from seafood nutritional quality to human nutrition and metabolism, within the context of exercise physiology and sports sciences. The project will also be pertinent to the older population, to guide retention of physical capabilities in later life.