I just tried out my max hold time and actually got my girlfriend to time me rather than counting in my head like I normally do. To my astonishment I realised my tempo of counting was double that of the watch! So holds I was sure I was going to be progressing on from I realised I was barely competent at. A hold I thought I was sure to get a minute was actually 30secs; I was gutted. Some exercises I may even have to drop back a progression. Since this happened I've downloaded an electronic metronome for my PC and set it to 60 beats a minute. Just thought I'd warn any newbies like me who might make this daft mistake. Anyone interested can download an electronic metronome from here for free:
http://www.nch.com.au/metronome/index.html
Failing that you could buy one, which would be much more portable than a PC, but I work out in my room. Think a cheep one is about 5 quid.