A sports scientist conducted an analysis of the relationship between consumption of energy drinks (measured in units consumed daily) and athlete performance in a physical test (measured by test score). He had found that there was a positive relationship between the predictor and the outcome variable. However when he introduced the variable consumption of protein (measured in daily calories obtained from protein) he found that the strength of the original relationship weakened. How might he now summarise the relationship between energy drinks and physical performance?
A) It has an indirect effect mediated by protein intake
B) It has a direct effect mediated by protein intake
C) It has no effect at all
D) It has no significant relationship.

Question

Quizplus · Accepted Answer

The weakening of the relationship after introducing protein intake suggests that protein intake mediates the effect of energy drinks on performance, indicating an indirect effect.

A Sports Scientist Conducted an Analysis of the Relationship Between