ISSA Trainer Practice Exam 2025 – Complete Study Resource

A calorie is defined as a unit of energy. This means it measures the amount of energy that food provides when consumed, as well as the energy expended by the body during physical activities and metabolic processes. Understanding that calories represent energy is fundamental in fields related to nutrition, exercise, and weight management, as it allows individuals to comprehend how much energy they are taking in versus how much they are using.

In the context of metabolic processes, calories play a crucial role, as the body requires a certain number of calories to function properly. For example, the basal metabolic rate (BMR) refers to the number of calories the body needs at rest to maintain basic physiological functions.

The other options do not correctly define a calorie. A unit of weight refers to measures like grams or pounds, a unit of temperature involves degrees (Celsius, Fahrenheit), and a unit of volume includes measurements like liters or gallons. Each of these categories pertains to different physical concepts that are distinct from the idea of energy measurement provided by calories.