In terms of saving energy, bicycling and walking are far more efficient means of transportation than is travel by automobile. for example, when riding at 14.5 mi/h, a cyclist uses food energy at a rate of about 400 kcal/h above what he would use if he were merely sitting still. (in exercise physiology, power is often measured in kcal/h rather than in watts. here, 1 kcal = 1 nutritionist's calorie = 4,186 j.) walking at 2.89 mi/h requires about 220 kcal/h. it is interesting to compare these values with the energy consumption required for travel by car. gasoline yields about 1.30 ✕ 108 j/gal. find the fuel economy in equivalent miles per gallon for a person bicycling.