Tackling 26.2 miles is a long way to run. Respect the distance and prepare for it. Confidence comes from being prepared.
Pace The best way to run your fastest possible race is by starting out at the pace you can maintain the entire race. So run the first mile at the pace you expect to average for the whole marathon. You can't put running time in the bank. You will end up losing more time in the end than what you gained by being "ahead of schedule" in the beginning. No matter how strong your will is, the metabolic condition caused by running too fast too early will force you to slow down during subsequent stages of the race.
While it may feel easy, especially in the marathon, to run the first mile of your race at the same pace as the last, your patience will pay huge dividends during that last mile. Ideally, the second half of your race should be equal to or slightly faster than the first half. This requires accurate knowledge of your fitness level, confidence to stick to your plan when others have taken the early pace out too fast, and a good dose of self-restraint. Your workouts are invaluable for providing you with knowledge of your fitness level and for predicting your average race pace.
Research has shown that fatigue can be delayed if simple carbohydrates (e.g., glucose and sucrose) are consumed during exercise. The carbohydrates should be easily digestible so they are absorbed quickly into the blood. Carry Gu packs or other gels or pick them up at an aid station and start ingesting them before you feel fatigued.
Despite all the recent attention given to hyponatremia (a decreased blood sodium content due to drinking too much water), the opposite problem—dehydration—is a much bigger issue. Water is vital for many chemical reactions that occur inside our cells, including the production of energy. When you sweat, you lose body water that can affect cellular processes. Also, your blood volume decreases and becomes thicker if you don't replace fluids. The result is a lower stroke volume, cardiac output and, ultimately, a decreased oxygen delivery to your muscles. Your running performance starts to decline with only a 2 to 3 percent loss of body mass due to fluid loss.
It's much easier to tuck in behind someone and let him/her pull you along than it is to maintain the pace on your own, so let other people do the work for as long as possible, especially if it's windy. The oxygen cost of running (and therefore the perception of effort) increases when you run into a headwind. Let someone break the wind for you.
When you run for long periods of time, you can get chafed in places you don't want to get chafed, which can make the marathon miserable. Apply BodyGlide or Vaseline before the race to any place that will be rubbed up against, such as inner thighs, nipples, and below your armpits.
Although the urge to go to the bathroom is often suppressed while running to conserve water, nervousness and anxiety often intensify that urge, so take care of business before the race.
Rehearse The day of the marathon is not the time to do anything different. Do at least some of your long runs in the same clothes and shoes you plan to wear for the marathon. Don't buy new shoes to wear in the race. Rehearse everything—shorts, socks, shoes, what you plan to carry on you, etc. Leave nothing to chance. Practice drinking water from a cup while running. Divide
It can be overwhelming to think of running 26.2 miles all at once. So divide the marathon into smaller segments. Focus on each 5K or even each mile at a time. If you're aiming for a specific time goal, focus on attaining that goal at each 5K checkpoint.