Grandma's Marathon has been run each year in June since 1977 in Duluth, MN. It is ranked in the top 20 marathons and in 1993 was ranked the ninth largest and fourth fastest in the United States. As Grandma's Marathon continues to grow each year, so do concerns for the runners' safety. A half marathon was added in 1991 and earlier race times have been implemented to make the race safer for the runners. During the years of 1989-1995, data from the medical tent, weather bureau, and race booklets were analyzed using odds ratios to predict factors associated with a need for medical assistance. The odds of needing assistance were almost two times higher before implementing the half marathon and the odds of needing assistance decreased with earlier start times. Except for 1994 when the race was later, the percent of finishers seeking medical attention has decreased each year, a fact that we feel is a direct result of these race changes. Thus, the addition a half marathon and earlier start times can help decrease the number of people needing medical assistance.