A researcher wanted to assess the effects of Diet and Exercises
on weight loss in 10 sedentary males.
The participants were enrolled in four trials: (1) no diet and no exercises;
(2) diet only; (3) exercises only; and (4) diet and exercises combined.
Each participant performed all four trials. The order of the trials was
counterbalanced and sufficient time was allowed between trials to allow any
effects of previous trials to have dissipated (i.e., a "wash out" period).
Each trial lasted nine weeks and the weight loss score was measured at the
beginning of each trial (t1), at the midpoint of each trial (t2) and at the
end of each trial (t3).
Three-way repeated measures ANOVA can be performed in order to determine
whether there is interaction between diet, exercises and time on the weight
loss score.