In a load testing apparatus, before the load test, three processor elements are combined, without overage or shortage, with a source processor element and a destination processor element as one pair, and the transmission time between the processor elements for each pair is measured. An indicator includes a pair of opposing side walls connected by a pair of opposing end walls, with an opening in the top of the indicator, the opening defined at least in part by a displaceable resilient tab, preferably two positioned on opposite sides of the indicator, attached to one of the side walls or end walls, wherein displacement of the tab enlarges the opening to admit the flange. Methods for supporting growth, accretion of lean body mass, and a healthy body composition in a preterm infant are also provided.