Spirit XT185 Owner's Manual page 18

STRENGTH
This program has a gradual progression of resistance up to 100% of maximum effort that is sustained
for 25% of workout duration. This will help build strength and muscular endurance in the lower body
and glutes. A brief cool down follows. Incline: There is a quick climb to a moderate, sustained elevation
that lasts the majority of the workout length.
INTERVAL
This program takes you through high levels of intensity followed by recovery periods of low intensity.
This program utilizes and develops your Fast Twitch muscle fibers which are used when
performing tasks that are intense and short in duration. These deplete your oxygen level and spike
your heart rate, followed by periods of recovery and heart rate drop to replenish oxygen. Your
cardiovascular system gets programmed to use oxygen more efficiently. Incline: This program will
spike similar to the speed profile, but in different segments (columns); this means that all of your
lower extremity muscles will be equally challenged throughout this program. The incline alternates
between 25 & 65 % of maximum elevation