"They were everywhere," Volquez said.
Volquez threw one pitch in the fifth inning of Sunday's loss before being removed from the game.
On Monday, Volquez said that he had felt fine warming up and in the first two innings. In the third inning, though, he started to feel some cramping in his legs. Later on, that cramping extended to his calves, hamstrings and his left oblique.
"I was pretty sore," he said. "In that fourth inning, it was pretty bad."
Volquez allowed two runs on six hits in four-plus innings. He didn't factor in the decision and finishes his first season with the Padres with an 11-11 record and a 4.14 ERA in 32 starts.
"I was pitching against one of the best pitchers in the game [Giants' starter Tim Lincecum] and I wanted to stay out there and compete," Volquez said. "It was our last home game, and I wanted to stay in there for the fans."