A single layer flexible foam includes the reaction product of an (A) isocyanate component and a (B) isocyanate-reactive component. The isocyanate component and the isocyanate-reactive component react in the presence of a (C) polyurethane gel. The polyurethane gel has a viscosity of from about 3,000 to about 12,000 cps at 25° C. and includes the reaction product of a polyol component and a second isocyanate component which react at an isocyanate index of from about 10 to about 70. The flexible foam also includes a plurality of agglomerated gel substrates that are formed from the polyurethane gel and that are dispersed in the flexible foam. The flexible foam is formed using a method including the steps of providing (A), providing (B), providing (C), and combining (C) with (A) and (B), such that (A) and (B) react in the presence of (C) to form the flexible foam.