As one who is new to endurance sports, I spend time researching diet & exercise,
and how best to optimize performance. I would suggest one
should experiment with pre and post workout diets, and by all means eat
"real food" not refined carbs. Your diet should not be any different from the rest
of the day. Eating unhealthy food before engaging in any exercise can cause additional stress on the body, i.e. high insulin levels, lower blood sugar levels, etc., which doesn't lead to improvement in one's physical fitness. Timing? Again, experiment and sense what your body can handle. I typically don't have a meal within an hour of running, but might have a homemade energy bar within 15 minutes of working out....just to ward off hunger pangs.