The leg muscles of a sprinter would differ from a marathon runner in that . The leg muscles of a sprinter would differ from a marathon runner in that . per gram, the sprinter's muscles would have more mitochondria than the marathon runner's muscles the marathon runner's muscles would have a greater rate of contraction than the sprinter's muscles per gram, the marathon runner's muscles would contain more myoglobin than the sprinter's muscles per gram, the sprinter's muscles would use more oxygen than the marathon runner's muscles