Final answer:
To assess the impact of exercise on adult weight loss, one must control dietary intake, exercise intensity and type, sleep patterns, stress levels, and baseline physical activity levels in an experiment.
Step-by-step explanation:
To understand how exercise affects weight loss in adults, one must control several variables in an experiment. The key variables to control include dietary intake, as dietary habits can significantly influence weight loss outcomes. Participants should consume a standardized diet or have their caloric intake monitored to ensure that weight loss.
Another variable to control is the intensity and type of exercise since different intensities and modalities can affect energy expenditure differently. Sleep patterns should also be controlled, as sleep can impact hormones that regulate appetite and metabolism.
Lastly, keeping the participants' baseline physical activity levels in check will help attribute any weight changes solely to the exercise intervention in the study. By controlling these factors, researchers can more accurately assess the relationship between exercise and weight loss in adults.