How to set up live heart-rate zones in your gym

Pulz8 displays each athlete's heart rate and training zone on a shared screen. To use it for group sessions, you need a compatible browser, Bluetooth heart-rate sensors and a display. This guide explains how to check your equipment, configure athlete profiles and introduce the board into your classes.

Equipment and browser requirements

Check the following before your first session:

• A computer or Android device with Chrome or Edge and Bluetooth. Use Windows, macOS, ChromeOS or Android. Pulz8 uses Web Bluetooth to connect to sensors. This connection is not supported in Safari or Firefox, or in standard browsers on iPhone and iPad.
• Compatible heart-rate sensors. Chest straps, armbands and watches must broadcast heart rate through the standard Bluetooth Low Energy heart-rate service. Compatible models are available from Polar, Garmin, Wahoo, Coospo and other manufacturers. Check the specific model rather than relying on the brand name. Sensors that support only ANT+ cannot connect.
• A TV or external display for group sessions. Connect your computer to the display, for example using HDMI. Each athlete's tile shows heart rate in beats per minute, percentage of maximum heart rate and the current zone.

Pulz8 runs in the browser without a separate installation. You can also add it to your desktop or Android home screen for quicker access.

Test your sensors before purchasing more

Test any sensors your gym or members already own. On the Pulz8 home page, select Test your device and choose a sensor in the browser's Bluetooth picker. The check connects to the sensor, confirms a live signal and disconnects. It does not display or save heart-rate readings. Pair the sensor again in Pulz8 to use it during a session.

If the check fails, verify the following:

1. The sensor is active and nearby. Put on the chest strap and moisten its electrodes according to the manufacturer's instructions. Check the battery and make sure Bluetooth is enabled.
2. A connection is available. Some sensors limit simultaneous Bluetooth connections. Disconnect the sensor from other apps or devices, then try again.
3. The sensor supports Bluetooth heart-rate broadcasting. ANT+ support alone is insufficient. Check the manufacturer's specifications for your model.

Check Bluetooth capacity for your class size

As a planning estimate, allow for approximately 7 to 10 simultaneous sensor connections per Bluetooth adapter. Actual capacity depends on the adapter and your setup. Test all the sensors you intend to use at the same time before the first class. A successful check of one sensor does not confirm capacity for the whole group.

The tiles resize to fit the display. Live readings reach the browser over Bluetooth, while saving a session requires an internet connection. Check both sensor connections and internet access before recording.

Set each athlete's maximum heart rate

By default, Pulz8 calculates zones as percentages of each athlete's maximum heart rate:

• Z1 Warm Up, gray: 50–60%
• Z2 Easy, blue: 60–70%
• Z3 Aerobic, green: 70–80%
• Z4 Threshold, orange: 80–90%
• Z5 Maximum, red: 90% and above

If no measured maximum is entered, Pulz8 uses 220 minus age. This is an estimate, not an individual measurement. Research on age-predicted maximum heart rate shows why an age-based formula should be treated as a starting point.

For example, the formula gives a 45-year-old athlete a maximum of 175 beats per minute. At 150 beats per minute, the board would show approximately 86%, placing them in Z4. If their measured maximum is 188, the same reading is approximately 79.8%, placing them in Z3. An underestimated maximum can make the displayed zone higher, but it does not shift every reading by a full zone.

Review the profile settings if the displayed zone seems inconsistent with the athlete's effort. Check the sensor signal as well. The highest reading in an ordinary session is not necessarily the athlete's true maximum. Pulz8 also supports zones based on heart-rate reserve for athletes with a known resting heart rate.

Assign sensors to athlete profiles

Link each sensor to the correct athlete. Pulz8 stores the assignment along with the athlete's maximum heart rate and zones, so it can be reused in later sessions. If your gym shares sensors, label them and check assignments whenever a sensor changes users.

Record and review a session

Select Start session to begin recording. After the session ends, the saved results include duration, average and peak heart rate, time in each zone and a heart-rate chart with the athlete's zone bands. The group view lets you compare athletes side by side and review how the recorded intensity matched the session plan.

A first-week plan for coaches

1. Introduce the board. Run a familiar class and explain what the tiles and colors show. Give members time to become comfortable with the display.
2. Verify readings and profiles. Check sensor contact, connections and profile settings when readings appear unexpected. Do not change maximum heart rate solely to produce a preferred color.
3. Introduce one zone target. Choose a suitable block, such as four minutes in Z3, and explain the target to the group. Use the board alongside feedback on perceived effort.
4. Review a recorded session together. Show the time-in-zone breakdown and discuss how it relates to the planned training load.

Pricing and next steps

Pulz8 is free for individuals. A gym pays €49 per month (or €490 per year) for the whole gym, regardless of the number of athletes. This price does not remove the Bluetooth connection limits described above.

You can explore the demo board without registering or book a 15-minute setup call. Before your first class, test your sensors together, verify athlete assignments and confirm internet access for saving the session.

Heart-rate data helps you monitor training intensity. It does not replace medical advice. If you have a heart condition or concerns about exercising, consult a physician before starting a training program.