Targeting excess body weight means you need to eat nutritious food, in the right quantity, for your height, age, and weight. This is a juggling act and will continually need to be altered. Unfortunately, people do race, and diet has come to mean deprivation. Deprivation is unhealthy and will never lead to a healthy sustainable weight loss. Use and follow this acronym for diet.
As I sat near the finish line with no medal around my neck, I still loved watching people complete it... and it made me want to do try it again. So don't be scared to attempt that marathon or half marathon on your bucket list because failure is only failure if you don't get out there and attempt it.