• High tech titanium casing for unsurpassed lightness and strength.
• OwnIndex™ - determines your fitness level in less than 5 minutes at rest using the unique Polar Fitness test.
• OwnZone™ Advanced - provides two levels of automatic intensity guidance with blinking and sounding alarms
• OwnCal™ - automatically shows your calorie usage
• Exercise Reminder - three days after the last exercise session displays a gentle text message every full hour
• You and I - user profiles for 2 persons - switch with a push of a button. Complete files for each user.
• Last exercise file - shows each user his/her exercise date, exercise time, time in the zone, Average Heart Rate, Fat consumption estimate, calories burned, total calories burned, total exercise time and OwnIndex
• In-zone indicator - A bullet appears for each 15 minutes in your Target Zone
• Heart rate monitoring
• Heart Rate Limits
• Heart touch - a hands-free way to activate the backlight
• Watch, alarm, calendar, weekday indicator and stopwatch functions
• Water resistant to 100 meters.
• Coded wireless transmitter that prevents cross-talk with other monitors

Nothing inspires you more into action than be able to see concrete results. As a active exerciser, the Polar M91ti Heart Rate Monitor lets you know exactly how effective your exercise program is.

For instance, the OwnIndex  feature lets you know your current physical condition simply by performing a quick Polar fitness test lasting a mere 5 minutes while at rest. The result, OwnIndex, predicts your maximal oxygen uptake, otherwise known as your maximal aerobic power (VO2max), a common indicator of one's aerobic fitness, from heart rate variability at rest, age, height, weight, sex and physical activity level during the past six months.

By knowing your current physical condition, you'll know how hard or often you should exercise to stay fit. And as you workout over the weeks, you'll be able to see the progress simply by taking the Polar Fitness Test again. To help you during your training, OwnZone Advanced  lets you train in both a lower intensity OwnZone Low for easy days or for weight management, and a higher intensity OwnZone High for deeper aerobic conditioning.

If weight management is your goal, the OwnCal  feature of the Polar M91ti shows you the calories burned during the workout. In these products even the percentage of the calories burned from fat rather than carbohydrates is calculated. While Exercise Reminders keep you motivated on your regular fitness program three days after your last exercise session. And if you still need justification to invest in a Polar M91ti Heart Rate Monitor, consider getting one to share with a friend. With the feature You and I, which stores the user profiles and exercise data for two people, both you and your friend can take advantage of the personalized features and measurements with one single button press.