Courtesy of WOWSA, Huntington Beach, California.

Some open water swimmers place a few extra gel packs in their swimsuits during competitive races, but not all.
But if a feeding is missed at a feeding pontoon along the race course, the extra gel pack or two certainly comes in handy.
What are gel packs made of?
Gel packs are small, easy-to-use, individual squeeze packages that contain simple and complex carbohydrates, antioxidants and amino acids in order to provide an energy boost during a race. Single-serving pouches are sold in a variety of sizes, shapes and flavors, and can be easily digested while open water swimming.
See also: Research on Energy Gel Packs For Open Water Swimmers and Triathletes