Polar RS300 X Heart Rate Monitor Watch Review

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Polar RS300 X Heart Rate Monitor Watch Review

To increase the effectiveness and strength of your daily workouts, Polar RS300 Heart Rate Monitor is the name you can trust. RS300X is useful in monitoring not only your heartbeat but also your target zones as well as calories burnt, lap times, the length of exercise and so on. The RS300X is a chest strap monitor, very comfortable to wear and useful in accurate monitoring of your heart rate. With its enormous tracking features and handy alarm bells, it has been rated in the Top Ten Reviews Silver Award amongst all the heart rate monitor reviews.

Polar RS300X Heart Rate Monitor Watch Review is available with all the latest functions at an affordable price. It is very much user-friendly, correct and smart looking watch. Menu functions, as well as a display screen, are also very good. In this monitor, all the desired functions are easily accessible that too without the help of any guide.

It has added a new feature of ‘Polar Index” to correlate your MVO2. To calculate your running distances on the very accurate scale it has been provided with a GPS linking facility. This watch has been specially designed for running and cycling purposes too, and it has come out with a foot strap also.

Watch has been provided a good chest belt with an option to fix transmitter with it. The role of the transmitter is to send cardiac data to wrist unit that is further displayed to you. Average heart rate and length of workout etc. are also measured with this watch. Calorie meter attached with it measures the total number of calories burnt in Kcal. Foot strap has been provided with thorough watch package as well.

The basic function of this is to measure your average speed while running, cumulative time, etc. The GPS technology attached to it helps to measure your running distance in a single go. The storage capacity attached to it is 99 laps.

Multi profile settings provided to it can create various heart rate target zone. With this feature, you can do many sports exercises with one watch on hand. The moment you are out of your target heart rate zone smart alarm feature warns you. Training machines at your gym or home can be easily synced with it. These helps not to watch your hand while exercising on various fitness machine apparatuses.


  • Up to the depth of 50 meters, the Polar RS300X has been provided with a water resistant display. Replaceable battery with a good backlight has also been provided to this monitor along with a zoom display option. Timer attached to it reminds you of the next coming event with a special event countdown feature. It has been set just before your event date.
  • Watch has been provided with a stop watch and an alarm too. During the times of need, the alarm can be snoozed. Format available for the setting of time is in 12 and 24 hours.
  • To integrate your running pace along with length covered watch has a G1 GPS sensor. Model of the foot strap attached to it is S1. Energy expenditure and accumulated burnt calories during the workout is calculated through the feature ‘Polar Own Cal.’ to analyze the total results it also tracks your latest 16 training sessions as well as last 16 weeks of workouts.
  • Display mode includes Heart rate as percentage of maximum heart rate, BPM, and average heart rate of total exercise
  • Track is maintained for your latest 16 training sessions and your last 16 weeks of training
  • It has been provided Visual and audible alarm in target zones: Every time it Informs your heart rate and speed/pace has exceeded the upper limit or has fallen below the lower limit of your target zone during a training session.
  • To provide a reference to base training intensity and measure improvement, it has been provided with Polar OwnIndex Fitness Test which calculates aerobic fitness (comparable to maximal oxygen uptake, VO2max). By providing Polar OwnCal, it depicts the energy you have expended while doing one exercise session. It will also show the kilocalories you accumulated during all the exercise sessions. The OwnCal helps to track both the energy expended and also the accumulated calories for a long time; it helps to achieve both short term and long term goals.
  • Total training time spent in your personal target zone is calculated by the Time in Target Zone feature provided to it. This feature can be used together with the Total Exercise Time to determine the effectiveness of your training program.
  • Number of laps – 99
  • Other features: alarm with snooze, dual time zone & stopwatch
  • Compatibility with Polar FlowLink (available separately)
  • Water resistant up to 50 meters depth.
  • Backlighting, display zoom also attached to it.
  • To keep the motivation level high Event Countdown Timer be referred as it keeps on displaying the number of days left for the next running event of yours (e.g., Berlin 23 days).
  • Very Simple-to-use wrist heart rate monitor/training computer in black as it helps you to train at the right intensity
  • It also provides metrics for heart rate, speed, distance, pace, and calorie burn
  • Track record of your latest 16 training sessions and your last 16 weeks of training
  • Other features include own zone feature for individualized zone training by heart rate or pace, a fitness test, and auto lap splits
  • It also has Polar WearLink+ 31 coded transmitter; compatible with S1 foot pod and G1 GPS Sensor.

Customer Reviews

Another feature that is very popular amongst its customers is that it is an awesome monitor to have given its price tag and the features attached to it.


Due to its sensitive buttons attached to it you have to very careful while operating Polar RS300X.  At the same time, Chest strap attached to it does not contain the same old cloth electrode portion. It has been replaced with the plastic one now. Therefore, it might create a problem with the moisture that could lead to inaccurate heart rate readings.


The Polar RS300X is in totality an exceptional purchase to Monitor the Heart Rate with so many user-friendly features attached to it. The main features include such as the multiple measurements display and the heart rate variability feedback that negate its very small drawbacks issues.

Finally, the RS300X is the more affordable. At the same time, the fact that the GPS system is separate might even make it a good purchase altogether for the users who do not always require the GPS feature. It would keep the option simple and comfortable at the next stage.