within-day energy expenditure
with·in-day en·er·gy ex·pen·di·ture(with-in'dā en'ĕr-jē ek-spen'di-chŭr)
A sports nutrition concept that incorporates time as the missing element in determining when someone needs additional nutrients. Proper nutrient timing takes into account the consumption of energy substrates in ideal proportions and the timing between eating, exercise, and physical performance. According to some researchers, when the right substrates are present at the ideal times, superior performance results.