Toddlers tend to have an abundance of energy. To put that energy to good use a fitness instructor creates a Toddler Fitness class. In this class the participants have to do everything the fitness instructor’s energetic toddler daughter does.
To compare the number of calories burned in Toddler Fitness versus the standard fitness class 40 volunteers are recruited. The volunteers are assigned at random to participate in Toddler Fitness or the standard fitness class. Each participant wears a calorie counting fitness watch. At the end of the class the calories burned by each participant is recorded and the average number of calories burned is calculated for each class.

After the classes ended, the instructor learned that the mean number of calories burned by the participants in Toddler Fitness was significantly greater than the mean number of calories burned by the participants in the standard fitness class.

Which of the following is the most appropriate conclusion?