Gluten-free seems to be the latest sports nutrition buzzword. Gluten is a protein in wheat, rye and barley that must be avoided by people with celiac disease
Whether you choose to listen to music or not, put your safety first! Make sure the music is not loud (consider wearing only one ear bud). It should not compromise your hearing and overly distract you to your surroundings.
Usually breathing is a natural process, but sometimes the physical effort of running may lend itself to quicker, more shallow breathing.
Although there are many other techniques to get motivated, it is important that you choose ones that work for you. Running a marathon is physically and mentally challenging, so you need to train your mind as well as your body.
When training for a marathon, the last thing you want is your equipment to distract you or slow you down. The right equipment can make all the difference.