A method and a system for determining an individual energy expenditure are described. In some embodiments, an energy expenditure can be calculated based on a combination of biometrics, heart rate and work rate. In some embodiments, a relative drag associated with the user can be calculated based on a group formation size, a group formation shape, participant velocities, weather, air density, and participant body surface areas. In some embodiments, a load adjustment factor can be determined based on the relative drag. In some embodiments, an adjusted energy expenditure can be determined based on the load adjustment factor.