5
Forerunner
®
205/305 Owner’s Manual
a
ppendIx
See the next page to learn about
the benefits of training in each
heart rate zone.
How can I determine my
heart rate zones?
If you know your maximum heart
rate, you can enter it and allow
the Forerunner to calculate your
Zone % of Max.
Heart Rate
Perceived Exertion
Benefits
1
50%–60% Relaxed, easy pace;
rhythmic breathing
Beginning-level aerobic
training; reduces stress
2
60%–70%
Pace comfortable;
slightly deeper breathing,
conversation possible
Basic cardiovascular
training; good recovery
pace
3
70%–80%
Pace moderate;
more difficult to hold
conversation
Improved aerobic
capacity; optimal
cardiovascular training
4
80%–90%
Pace fast and a bit
uncomfortable;
breathing forceful
Improved anaerobic
capacity and threshold;
improved speed
5
90%–
100%
Pace a sprinting effort,
unsustainable for long period
of time; labored breathing
Anaerobic and
muscular endurance;
increased power