My gym has one of these. They're not the greatest but they do give an indication.
http://www.hce-uk.com/WebRoot/ePagesForSAPlarge/Shops/Healthcare/4DDD/BED2/956A/6759/EFC7/0A0C/05E9/AEF2/BCH049.jpg
@user16171 started
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My gym has one of these.
They're not the greatest but they do give an indication.
http://www.hce-uk.com/WebRoot/ePagesForSAPlarge/Shops/Healthcare/4DDD/BED2/956A/6759/EFC7/0A0C/05E9/AEF2/BCH049.jpg