The Forerunner 45 personalizes how you train. Learn how your body responds to: exercise, rest and sleep. The Elevate optical heart rate monitor takes your pulse straight off your wrist, no need for a chest strap. 

• Built-in activity modes for biking (outdoor), running (outdoor) and walking, with more activities unlockable through free the Connect app, like elliptical training, biking (indoor), running (indoor) stair stepping, yoga and more.
• A powerful, internal antenna connects to 3 different satellite constellations, GPS, GLONASS and Galileo. Multiple networks, combined with satellite position caching, give you a fast connection and a strong GPS signal wherever you are.
• Internet Live Tracking during activities.
• V3 low-profile Elevate™ optical heart rate monitor provides reliable constant heart rate data and allows you to train without a chest strap.
• Broadcast of your HR over ANT .
• VO2 max data lets you see how efficiently your body uses oxygen.
• Incident detection: in case of accident, the unit sends a signal through your phone to your emergency contacts.
• Assistance mode sends out a predefined message (through your phone), to you emergency contacts so they can keep an eye on you.
• Body Battery™ mode monitors what drains your energy (exercise) and recharges your energy (rest, food, etc.), you get a better idea of how, and when to train.
• Garmin Coach provides free, personalized training plans through Garmin Connect.
• Stress level score monitors heart rate variability while inactive to produce a stress score, and helps guide you to reduce stress.
• Move bar reminds you to move after being stationary for too long.
• On board sleep tracking mode monitors total sleep hours and restful sleep.
• Smart notifications (emails, texts, alerts and more) come in via Bluetooth connection to your smartphone.
• Automatically sync your data to a paired smartphone running the free Garmin Connect app.
• Connects with ANT and Bluetooth Smart, from foot pods, to speed and cadence pods (not power meters or Varia lights).
• Connect IQ support allows you to download custom watch faces.
• Intuitive 5-button interface works with and without gloves and in all weather conditions.
• Always-on, colour display is bright and clear in any conditions.
• Internal memory stores up to 200 hours of activities. Garmin Connect will store all of your activity data.
• Battery lasts up to 13 hours in GPS mode or up to 7 days in watch mode.