24 ANT+ SensorsFitness goalsKnowing your heart rate zones can helpyou measure and improve your fitnessby understanding and applying theseprinciples.• Your heart rate is a good measure ofexercise intensity.• Training in certain heart rate zonescan help you improve cardiovascularcapacity and strength.• Knowing your heart rate zones canprevent you from overtraining and candecrease your risk of injury.If you know your maximum heart rate, youcan use the table (page 49) to determinethe best heart rate zone for your fitnessobjectives.If you do not know your maximum heartrate, use one of the calculators availableon the Internet. Some gyms and healthcenters can provide a test that measuresmaximum heart rate.More Heart rate Options• Heart rate alerts (page 9)• Heart rate zone calculations(page 49)• Heart rate data fields (page 36)• Heart rate troubleshooting(page 48)Foot PodYour Forerunner is compatible with thefoot pod. You can use the foot pod to senddata to your Forerunner when trainingindoors, when your GPS signal is weak, orwhen you lose satellite signals. The footpod is on standby and ready to send dataas soon as you install it or start moving.You must pair the foot pod with yourForerunner (page 22).When the battery is low, a messageappears on your Forerunner.Approximately five hours of battery liferemain.Choosing Your Speed SourceIf you plan to train outdoors, you can setthe Forerunner to use foot pod data tocalculate pace rather than using GPS.1 Select MODE > Settings > runSettings > Foot Pod > Yes.2 Select Speed Source > Foot Pod.