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06 Dec 2004  -  Finland

Polar S725 cycling heart rate monitor

Polar's S725 heart rate monitor is intended specifically for cyclists, combining a multitude of HR measuring tools with a number of useful on the bike functions and some pretty handy analysis software.



Finnish company Polar Electro was founded in 1977 and can be considered largely responsible for the boom in the use of Heart Rate Monitors for measuring athletes' performance. The company now operates in 50 countries and employs 1400 people, with net sales of €144 million (2002).

Despite the rise of affordable power measuring devices in recent years (Polar makes one of these), just measuring your heart rate both during and post exercise can still be very informative. As our fitness panel will tell you, there are many things that can affect your heart rate, such as weather conditions, training duration, nerves, illness and food, but armed with this knowledge and a bit of experience of how your body works, you can certainly use a heart rate monitor to your advantage when training.

Case in point: I had a nasty virus at the beginning of the year which kept me off the bike for 10 days. Doctors also recommended that I don't train "hard" for an additional four weeks until the virus had completely gone, otherwise there was a risk of dropping dead from a heart attack. I have to say that I wasn't particularly enthused by that happening. To me, not training hard meant not going anywhere near my red zone, and fortunately I had just received a beta model of Polar's new S725 cycling heart rate monitor. So I followed the advice and was able to ride at a low to medium intensity for a month.

Now, many months down the track, I'm writing this review, and while I might feel like death warmed up on some occasions, at least that's just a feeling and not the reality. Did Polar Electro save my life? Well, it didn't stop me from stupidly riding in the snow...

The test unit

I tested a beta model of the Polar S725, which back in February, 2004 was not yet available to the general public. The wrist unit is a fairly solid piece of equipment: the large LCD display is encased in polycarbonate and glass fibre with a slightly gimmicky carbon fibre weave finish. There are four function buttons (two on each side of the unit) and one large red button which is the start/stop button. The wrist strap is made of polyurethane with a stainless steel buckle. It is 30m water resistant (which in wristwatch water resistance terms means you can get it wet, but not go swimming in it) and takes a CR2354 battery, which Polar claims will last two years if used for two hours a day, every day.

The chest transmitter is made of polyamide, takes a CR2025 battery which will last an average of one year if used every day for two hours, according to Polar. The transmitter is also 30m water resistant. The chest strap is made of a combination of polyurethane, polyester, polyamide, nylon and natural rubber, and is designed to be comfortable without creating any problems for data transmission to the wrist unit.

The Polar S725 also came with a cordless speed sensor, constructed of polyamide and mounted to the front fork via two plastic cable ties. There was a handlebar mount for the wrist unit that also attached by means of a couple of cable ties. The Polar S725 can be used with Polar's chainstay mounted power sensor, but that wasn't supplied with this unit.

For communication with a personal computer/laptop, this beta unit came with Polar's infra-red (IR) interface for a USB port. However, the Polar S-series Toolkit software hadn't been tweaked to interface correctly with this device. Fortunately, the wrist unit's IR sensor could communicate with the IR port on the back of my laptop, so I could download all the data and analyse it via the S-series Toolkit software. Another option is to download the data to a Nokia 5140 mobile phone (Finland rules, OK?). You are then given a summary of the session and can send it to a PC, Polar's Personal Trainer web service or another mobile phone.

Recommended retail price: US$350

Total weight: 170g

Wrist unit: Polycarbonate/glass

Transmitter and chest strap: Polyamide, polyurethane, polyester, polyamide, nylon and natural rubber

Speed sensor: Polyamide

Colour: Black/carbon weave