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Not only have I lost the chest strap to my beloved HAC4 cycle computer, but the TANITA scales have given up the ghost this weekend. So, I can't record my HR zones as I train and I can't track my weight loss. Hell, the HAC4 is one of my favourite gadgets, I used my own software to import data into my training log software.

So I spent Saturday trying to decide what to do about my cycle computer, given the HAC4 is discontinued and getting a belt is quite a challenge (I wish you could 'watch' on ebay for stuff being listed). I narrowed it down to the Garmin Edge 305 versus the Polar S725X. The Garmin came out top for ease of use and innovation with the mapping software like memory map. But when it came down to it I'm looking for a cycle and run heart rate monitor not a GPS tool. The Garmin has limited battery life and limited data capture according to most reviews I've read, so I bought the Polar and am waiting for it to arrive. I went for the cadence and usb IR interface but stopped short of the unbelievably expensive power kit (£200 for a few wireless sensors!?).

Went to Argos in Guildford this afternoon and bought some replacement TANITA scales. Argos might be a little chavvy but their prices are good and they have a strong range of body fat scales. Managed to get some scales that measure total body water as well as fat percentage for £50, that's half the price I paid for the old ones, although they aren't glass which was a waste of money to be honest -- how often do you even notice your scales let alone admire their aesthetics. Bah humbug.

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To explain the math here are his words;

I posted a comment on you Blog post on optimising the Wbal model. I've done some more thinking and I defn think it can be done without visiting the previous samples as the Skiba formula can be decomposed further, i.e. From your blog I believe the integral part of the equation is:

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