electronic body fat readings?

[motive]

my gym has one of these where you enter the height and weight, type of build and age... it comes up with a bf% after you grip it for abotu 10 seconds. doesnt seem like it could be accurate but whats your opinions on these

 

[jonny21]

bio-electrical impedence. Too dependant on hydration levels. It'll give you a good general idea.

 

[IainDaniel]

Garbage.