Matrix Matters: Yolk-Driven Effects for Exercise Recovery

The three acute dietary interventions are as follows: • Whole eggs (WE): e.g., 3 whole eggs (volume will be standardised across participants to provide 18 g protein from eggs), prepared as a standardised omelette with vegetables, toast and 300ml of water and no added fat. • Egg whites (EW): egg-white equivalent to match protein target (e.g., ~250–300 mL liquid whites standardised to provide 18 g of protein), prepared in the same recipe format as above with vegetable oil added to match fat content above. • Whey protein (WP): flavoured shake providing the same protein dose along with toast as above with water provided to match fluid intake above and vegetable oil added to match fat across conditions. As well as the treatment arms described here, participants will also complete a standardised exercise protocol as the Exercise Induced Muscle Damage (EIMD) intervention. This exercise is comprised of 30 sets of 10 reps of maximal eccentric leg extensions on an isokinetic dynamometer. Intensity is defined as maximal on each repetition. This exercise intervention is to be administered and supervised by members of the research team with extensive prior experience in similar exercise interventions (Dr Urwin, Dr Convit, Dr Hamilton). The dietary interventions will commence immediately following the conclusion of the EIMD, and all food is to be consumed within a 30 minute period. The 30 minute ingestion period also applies to the subsequent days within each treatment (i.e. the three days following EIMD). The dietary intervention is to be designed by a dietitian within our team (Dr Convit), and delivered by members of the research team with extensive experience in acute feeding studies (Dr Convit, Dr Urwin). Adherence to the first meal is confirmed by the research team. Adherence to subsequent days is confirmed by the participants. Each trial is separated by a 14 day washout period. With limb alternation, washout between limb repeats is equal to a minimum of 31 days (two 14 days washouts, plus the 3 day intervention on the alternate limb). For a sub set of participants (n = 10, equal numbers M and F), we will we will perform amino-acid profiling (liquid chromatography-tandem mass spectrometry; LC-MS/MS) and fatty-acid profiling (GC-MS) at baseline (pre-meal) and every 10-20mins for the 3 h post-meal window during each period. This involves collection of venous blood samples via cannulation at the prescribed intervals, during which time participants stay seated and complete sedentary activities only (such as reading, watching TV). Cannulation and sample collection is to be completed by phlebotomy trained and experienced members of the research team (Dr Urwin, Dr Convit). Venous blood samples collected will be centrifuged to collect plasma, which will be frozen for later analysis. This sub set of participants is selected as the first 5 male and the first 5 female participants to ensure adherence to the planned sample size.