I started lifting weights (again) and accurately tracking my progress (I bought a “cheap” workout and weight loss plan, which requires a lot of data so you can see your progress (or regress)). When bench pressing and doing squats on the (Cybex) Smith Machine I had assumed that the bar weighed 45 pounds like a free bar does and added it to the total weight. It wasn’t until my most recent session (finished about 30 minutes ago) that I realized that the bar doesn’t in fact weigh 45 pounds…but weighs anywhere from 7 to 30 pounds, according to what I saw from a quick search. I should have realized that it wasn’t 45 pounds because it felt pretty light. Google says that the average weight tends to be about 15 pounds, but I have no idea.
I was also using the (Cybex) overhead should press machine and saw that the plates past 50 pounds went in 15 pound increments. Then I noticed the additional weight at the top, disabled by a pin. When I lowered it down on to the stack there was no number on it. Was it 5 pounds? 7.5 pounds? 10 pounds? Who knows?
How are people supposed to know how much weight they’re lifting if things aren’t numbered properly? They have these huge stickers that say everything, but they can’t put “bar weighs 15 lbs” on it?
I agree with wanting to know the empty weight for machines. For my leg press at home, I forgot to weigh the sled/carriage before fully assembling the machine. So I did the next best, which was to measure the uphill force of the carriage at its 45 degrees, using a cable that pulls uphill and dangles vertically off the top of the machine. I then progressively loaded the cable with plates until it started to move the carriage.
The force uphill is sqrt(2) of the carriage weight, so I multiply the plates by 1.41 to arrive at the empty weight. This is only useful when I compare to the leg press at the office gym, though.
That is some ingenuity! Smart move.
I am lucky that I have been working with a trainer for a couple years, and she knows this info for every piece of equipment in my gym. It will get harder as I taper off working with her.