Polar RCX3 Polar Running Index

A good way of improving stride length is to undertake specific strength work, like running hills, running in

soft sand, or running up steps. A six-week training period including strength work should result in

noticeable improvements in stride length, and if combined with some faster leg speed work (such as short

strides at best 5km pace), noticeable improvements should be seen in overall speed, as well.

*Optional s3+ stride sensor required.

Polar Running Index

Running Index offers an easy way to monitor performance changes. Performance (how fast/easily you run

at a given pace) is directly influenced by aerobic fitness (VO2max) and training economy (how efficient your

body is at running), and Running Index is a measurement of this influence. By recording your Running

Index over time, you can monitor progress. Improvement means that running at a given pace requires less

of an effort, or that your pace is faster at a given level of exertion. The Running Index feature calculates

such improvements. Running Index also gives you daily information on your running performance level

which may vary from day to day.

Benefits of Running Index:

• emphasizes the positive effects of good training sessions and resting days.

• monitors fitness and performance development at different heart rate levels - not only during maximal

performance.

• you can determine your optimal running speed by comparing running indexes from different kinds of

training sessions.

• stresses progress through better running technique and fitness level.

Running Index is calculated during every training session when heart rate and the s3+ stride sensor or G3/

G5 GPS sensor* signal is recorded, and when the following requirements apply:

• speed should be 6 km/h / 3,75 mi/h or faster and duration 12 minutes minimum.

• heart rate should be at least 40% of your HRR (heart rate reserve). Heart rate reserve is the difference

between maximum heart rate (HRmax), and resting heart rate (HRrest)

Example:

A person with HRmax190 bpm and HRrest 60 bpm

40% (190-60) + 60 = 112 bpm (heart rate should be at least 112 bpm)

Make sure that the stride sensor is calibrated. Calculation begins when you start recording the session.

During the session, you may stop once at traffic lights, for example, without interrupting the calculation.

In the end, your training computer displays a Running Index value and stores the result in the Training

files section. Compare your result to the table below.Using the software, you can monitor and analyze

your progress in Running Index values against time and different running speeds. Or compare values from