Measuring heart rate is the most affordable way to have a measure of the effort made. For this reason, the use of a heart rate monitor to have a reference for the intensity level of our pedal strokes continues to be popular. However, its use has had the historical toll of the need to use the chest strap, which is unbearable for many. Now, optical sensors seem to be the alternative.

Since the mid-1980s, when the first portable heart rate measurement devices began to appear, heart rates became a useful tool for knowing the intensity of the effort made during sports activities, including cycling.

As the years went by, this way of quantifying intensity became cheaper and miniaturized until it was available not only to competitive athletes, as was the case in its beginnings, but to practically any athlete.

Despite the democratization of power meters in cycling, pulses are still widely used. Even those who use power as a reference continue to consult heart rate as a reference for how training impacts the body and how the body assimilates efforts.

However, all this did not end with one of the essential elements for measurement, the chest strap capable of detecting the electrical impulses produced by the heart and transforming this information into beats per minute data that were transmitted to the watch or cycle computer to display them. on the screen.

A gadget that many have always found to be tremendously uncomfortable when doing physical activity despite the fact that current models have fully adaptable elastic straps and do not need to be as tight to fulfill their function as was the case with the original models.

Apart from the aspect of comfort, the straps and their sensors have always suffered from poor durability due to their clear exposure to sweat generated by physical activity that ended up surpassing any seal and damaging the electronics, no matter how much care we took. with them.

A few years ago, with the spread of smart watches and sports models designed specifically for running or triathlon, optical heart rate measurement began to be introduced. A system based on an LED that passes through the skin, illuminating the blood vessels so that a sensor is capable of detecting the volume variation in them that occurs with each heartbeat. Technology that is also used to measure oxygen saturation in the blood.

Although this type of measurement is widely used in the field of medicine, at the sports level in its beginnings it posed quite a few problems of precision, in many cases yielding erratic information in the initial models as it depended on various factors, from the tone of the skin, if placed on an area with hair or sweat produced during exercise. Also the placement of the sensor, which had to be very close to the skin to obtain reliable readings.

Over the years, these sensors have evolved, appearing, in addition to those present in sports watches that obtain their data directly from the wrist, bracelet-type sensors replacing traditional pulse bands.

It has also been improving the precision of the sensors to make them less sensitive to the conditions we mentioned before, using different light frequencies in their LEDs and using more advanced signal interpretation software.

Currently, most optical sensors are capable of achieving a precision very close to that offered by traditional tapes, which, for most uses, is usually sufficient. Only those who carry out more specific training might miss greater precision when performing intervals, but, let’s face it, this type of cyclist is probably already using power measurement for their training.

This is why optical sensors are gradually relegating traditional chest straps in the market. In fact, in brands like Wahoo, their chest straps have been out of stock for a long time, with no signs of them being back in stock. be available.

Apart from all the models of sports watches and smartwatches on the market, several brands have launched bracelet-type sensors that, through the usual ANT+ or Bluetooth connections, we can link with our cycle computer to have heart rate data. These are some of the most popular.

Polar Verity Sense

It has 6 LEDs for greater precision as well as three operating modes that add to the normal reading, a pool operating mode and another recording mode in internal memory in which the data is stored to be downloaded later. It only uses Bluetooth transmission so it may not be compatible with all cycle computers. All this in a device that weighs just 5 g and has a price of €99.

Wahoo Tickr Fit

This band is designed to be placed on the forearm rather than as a bracelet in the bicep area, perhaps a less practical placement for cycling. It has a rechargeable battery that provides up to 30 hours of battery life and a price of €79.99.

HR Choirs

Minimalist design with a sensor housing that prevents any external light so that the measurement cannot be interfered with for this reason. It only has Bluetooth data transmission, which we will have to take into account when establishing compatibility with our cycle computer. It has a price of €79.

TwoNav Arm Heart Rate Sensor

Designed to be placed on the forearm, it has ANT+ and Bluetooth transmission so it is compatible with practically all devices on the market. It has a price of €47.20