GLOSSARY

Energy Deficit Reference Table

Arithmetic examples of daily balance; energy expenditure adapts and short-term scale change is not identical to tissue-energy change.

Energy Deficit means that expenditure exceeds intake over the interval considered, reducing stored body energy overall. The tissue composition and performance consequences depend on the athlete and circumstances.

For example, an athlete's scale weight can rise after restoring carbohydrate despite no convincing evidence of fat gain. Review glycogen, fluid and the longer-term intake and expenditure pattern before labeling the change a sustained surplus. The energy model remains useful when the changing material and time interval are identified correctly.

Over a defined interval, a difference between metabolizable energy intake and energy expenditure changes stored body energy. This principle does not imply that daily scale weight directly reveals energy balance. Water, glycogen and gut contents also contribute to body mass. Intake and expenditure influence each other through behavior and physiology, so projecting the same daily deficit indefinitely creates unrealistic predictions. Interpret the energy equation together with its timescale and the composition of the tissues changing.

Total expenditure includes energy needed at rest, the thermic effect of food and physical activity. Planned exercise is only part of activity expenditure. Work, walking and spontaneous movement can also matter. When an estimate already includes a component, adding it again double counts energy. Establish whether an exercise value is gross or net of resting expenditure, and use the same convention when comparing days or combining wearable estimates with a daily energy model.