My experieneces with the Polar RS800CX and the Suunto T6D

I own a Polar RS800CX that has served me very well for more than a year, averaging more than 2 hrs of use every day. Changing the battery in the wrist unit was quite a challenge. The seal is too tight to pry loose with a coin. So I used my Exacto to scrape lose the salt caked in the case-cap crevice and then resorted to a 12 in. long screwdriver with a quarter inch head to unscrew the cap. The notch soon wore out, so I cried Uncle and the good folks at Polar sent me a harder case replacement. The strap snapped off the wrist monitor and again Polar sent me a replacement but let me figure out how to get it on. It was easier than doing a Rubik's cube but I now believe that Nordic folks like to hand you little riddles by way of saying hello.

I also came upon FirstBeat Athlete, a standalone analysis software that can read .hrm files directly from the RS800CX. That, got me hooked on two new measures, Excess Post exercise Oxygen Consumption (EPOC) and intensity of training -the so called Training Effect. The brute force way to determine EPOC would have you lay supine in a chamber after a workout and measure the (excess) amount of oxygen you breathe in until you return to your base metabolic rate (and stop panting). Turns out that EPOC can be inferred from heart rate data and other basic biometrics and FirstBeat Athlete has productized this.

My current weekly routine consists of one long weekend run, one session of interval running, and another to nudge my lactate threshold (VO2_LT) forward. I can estimate VO2 from my heart rate reading especially once I calibrated against a  sub-maximal VO2 treadmill test. Interval running is easily tracked based on speed and duration. The 10 to 15 mile weekend runs, which I prize very much, leaves me adrift quantitatively. What is my axis of exertion? Calories burned, time spent, distance covered, cadence, steady state heart rate are easily tracked individually. But, is there a measure that tracks how runners deplete as they tackle terrain and elevation with their speed and gait? I think the answer is EPOC. Knowing your past EPOC scores, you can more deliberately throttle your long runs, whether it is to stay in familiar territory or break new ground. In particular, you can start to reduce your EPOC even while running by lowering your pace just a bit and can even pace yourself to hold EPOC steady.

The Polar RS800CX can not display EPOC in real time but the Suunto T6D will display EPOC in real time.  The Suunto T6D presents a new set of riddles. The D in T6D stands for dual heart rate transmitters, one of which digitally pairs with the wrist unit and the other one broadcasts and hopefully various exercise equipment can track and display heart rate data on their usually larger screens. You can always finagle this by wearing two heart rate belts, especially if you have an old one lying around. My experience with the T6D has been disappointing, unless I am running very close to the front, LifeFitness  treadmill displays at my gym latch on to some other person's monitor or blank out.

I bought the sleek looking T6D Black Flame. I regret it now because the faint dot matrix style yellow on black characters don't show very well except in broad day light. The menu system is more intuitive than the Polar but it is best to tinker with it till you get it right rather than try to read about it. There are better instructions on the Suunto website than in the fat multi-language instruction booklet that you receive with the unit.

The Suunto foot pod pairs quickly with the T6D wrist unit. Pairing or repairing the Polar foot pod with the RS800CX takes more attempts. But the accuracy of my Suunto unit is worse. With the treadmill set to 2 mph, the Suunto shows 2 mph, when the treadmill cranks up to 3.5 mph and I break into a light jog, the Suunto meanders around 5.6 mph. When I am running  at 7 mph on the treadmill, the T6D shows about 7.8 mph but at 8 mph there is no discrepancy. So the deviation is non linear. I am not sure if a simple scale factor, which is all you can set on the wrist unit, can correct this. Maybe the Suunto foot pod is more sensitive to irregular gait. The Polar foot pod has always been in perfect agreement with the treadmill readout. The Polar foot pod also senses stride length and running cadence (steps per minute) which the Suunto foot pod does not.

The start/stop button on the left starts a session but does not  actually end a session. That button functions as a pause/resume button once you have started the recording. To end a session you first hit the start/stop button to pause and then hold down (not just tap) the button marked "lap" on the right. The lap button also acts as a traditional lap marker. So to stop, first pause and then hold down lap long.

The USB data sync works like a charm once you have the Moveslink software installed. To get to it you go to the Movescount website and click on a tab, currently called "Connect to Movescount", then you click on a button labeled get Moveslink Software and the rest is a breeze. The Movescount website is the best part of the Suunto experience. It is a classic social networking site with everything you would expect. I have missed this sort of interactive space and enjoy very much the ability to network with others whose bodies respond to exercise similar to mine.

I wish the the analog heart rate transmitter and the foot pod, were more robust. Yet, the activation of the Movescount community adds a new dimension that makes the investment very worthwhile for me. If data enriched social networking is important for you, then Suunto will appeal to you. If exercise is a solitary pursuit and accuracy and robustbness are more important then the Polar will appeal to you. I get to wear both!