Race runners: There are three key things to get right before a long run, whether it is a training run or the main event itself. Firstly, be hydrated, especially if the weather is warm and taking on water during the run is difficult.
Second, be replete with energy. The night before an endurance activity should include a balanced main meal (there isn't a great need to hugely 'carb load' unless you want to add a little fat to yourself!) and at least 2 hours before the activity itself a meal that contains slow-release carbs may be ideal. Whole oats porridge is my go-to for this.
Thirdly, warm up appropriately. Walk, jog, increase blood flow to the muscles being used in the activity and gradually increase intensity during the warm-up. On the start line, single leg calf raises prep the calves for the hard work they're about to be asked to do and may reduce injury risk.
New runners out for a short run: Focus on a thorough warm-up, just as the race runners would. That may be 1 minute of air squats before leaving the house to warm up all lower body musculature or maybe 20 of the dreaded burpees! Build up from either a fast walk or light jog into your steady running pace gradually. Don't rush into doing high intensity intervals or sprints as the risk of injury will increase. Post-run, take on water and consider a short cooldown routine which may include static stretching. The Echelon Fit App contains a selection of ideal workouts.