A model for glucose metabolism during exercise is developed for use in an automated insulin delivery device. Key changes that occur in the body during exercise are an increase and redistribution of blood flow, increased glucose uptake, and increased glucose production by the liver. A model of glucose and insulin metabolism for exercise intensity less than or equal to 60 percent VO^max₂ and duration of less than or equal to 90 minutes has been constructed. The model-generated glucose profiles are consistent with physiological behavior over this time period based on comparisons with literature data.