To demonstrate how to calculate ANOVA with repeated measures, we will analyze
a hypothetical study. A graduate student studying motor behavior was interested in
the decrease in balance ability that bicycle racers experience as their fatigue from
the race increases. To measure this, the researcher placed a racing bicycle on a
roller ergometer. The bicycle's front and rear wheels were placed on the tops of
cylindrical rollers so that as the wheels turned, the rollers turned and the rider was
able to ride in place (figure 10.1 ).
A 4-inch-wide stripe was painted in the middle of the front roller, and the rider
was required to keep the front wheel on the stripe. The rear rollers were connected
to a braking system to provide resistance to the rear wheel of the bike. Balance was
indicated by wobble in the front wheel and was measured by counting the number
of times per minute that the front wheel of the bike strayed off the 4" stripe.
As resistance on the rear wheels increased, physiological fatigue increased, and
it became more and more difficult to maintain the front wheel on the stripe. Subjects
rode the bicycle for 15 minutes, divided into five 3-minute periods for the
purpose of collecting data. Data were collected on the number of balance errors