Will smaller field names improve performance?

I have a flat document with 44 fields. One index has 120577177 documents. When our aggregation returns from es the size of the json is around 14-20mb. When doing load testing a query depending on the date range will take 7 - 30 seconds to run(Hitting elasticsearch api directly). Will reducing the field names improve performance, either on the aggregation or shuttle the data from elastic search to my java app?

Thanks,

Jonny

What query do you run exactly?