I'm working on a trial and would really like some suggestions on how to analyse my data.
The study is a randomised crossover trial. I am interested in glucose response to three different lengths of an exercise. Each invididual will undergo one of three different lengths of exercise per lab day (0, 30 and 60 minutes). There are 6 measurement periods: pre exposure, post exposure time 1, 2, 3, 4 & 5.
Data is assumed to be normal
Dependent continuous: glucose
Independent categorical: exercise length (0, 30 and 60 minutes)
I have a two questions: #1 Would repeated measures (within subjects) anova be appropriate in this case? Or is linear mixed model more appropriate?
#2 However, I also plan analysing by age (older and younger adults) as I want to know if the age of participants effects the outcome. Would this case mean that I could use age as a covariate and therefore use ANCOVA? Or maybe something else?
Thanks in advance