-----Original Message-----
From: garmin_forerunner_305@... [mailto:garmin_forerunner_305@...]On Behalf Of David Cochrane
Sent: 16 June 2008 16:14
To: garmin_forerunner_305@...
Subject: Re: [garmin_forerunner_305] altitude & distance

Ed - suspect that there's a pretty simple explanation for that.....

Here's my "ex RN navigating" feeling on it - GPS measures distance by calculating frequency shifts between different  satellite clock signals and effectively measuring movement across an imaginary great circle that equally bisects the globe at all angles, ie the equator (this is where nautical miles come from). Because you're trogging up and down vertically with very little great circle between your routes, your horizontal movement isn't that great - you really need something with an inertial movement capability (measuring shifts away from a datum or standard point) to accurately tell you how far you've travelled up hill and down dale so that movement across the globe is really irrelevant. I'd suggest the Polar RS800SD as a SUPERB product for this - I loved mine but needed Mac compatability which is why i ended up on the Forerunner. You can also add a GPS sensor to the RS800SD if you really want that functionality. 

Hope this helps.

Dave

On 16 Jun 2008, at 09:51, Ed Dowding wrote:

That's.. annoying.

So whilst running around the mountains doing altitude training, not 
only is it harder work because there's less oxygen, but it also 
registers me as going less far!

Sigh.

Ed

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On 16 Jun 2008, at 10:44, Tris wrote:

> Hi
>
> No, it doesn't
>
> Regards
>
> Tristan
> www.heartratemonitor.co.uk
>
>
>
> -----Original Message-----
> From: garmin_forerunner_305@yahoogroups.co.uk[mailto:garmin_forerunner_305@yahoogroups.co.uk 
> ]On Behalf Of Ed Dowding
> Posted At: 13 June 2008 22:45
> Posted To: Info@BHIP
> Conversation: [garmin_forerunner_305] altitude & distance
> Subject: [garmin_forerunner_305] altitude & distance
>
>
>
> Does the garmin take account of changes in altitude when measuring
> distance, or calculating calories?
>
> Ed
>
> 70% of our clients use their PAs to find them new business, thereby
> covering costs and generating extra income.
>
> Intelligent and versatile personal assistants
> www.onlinepersonalassistant.com
>
> ***
> Ed Dowding
> ed@onlinepersonalas <mailto:ed%40onlinepersonalassistant.com> 
> sistant.com
>
> +44 (0)207 193 2999
> +44 (0)7775 79 18 14
> Skype: eddowding
>
>
>
>
>