If you're thinking speed equates to weight in shoes, it can and does influence but if that's your worry, you're either extremely fast that you podium races and ounces equal seconds or you might think brands are the greatest. At least for me that's line of thinking is more a cyclist who praises their 3k-8k carbon fiber bikes and does little to no effort in training, but fuck it I look good. Feet and knee care are a good thing to have in mind.  Static and dynamic stretching before and after runs, using a wobble board or resistant bands for stretching to strengthen your core. A lot of core exercises will greatly work on your speed if that's what you want. Learning good form and maintaining form make for an easier run on your body in general. There's a saying and I know I'm butchering the phrase, but you get endurance from your long runs and your speed on the track. Meaning a high interval training once in awhile will boost speed.  I hope that clarifies your question.