I was just thinking (daydreaming) about setting up a system where your lifting generates electricity for your home. I don't know how much electricity could be generated, but here are a couple ideas I had. Like a grandfather clock can run for so ling by having heavy weights pulling down on a chain that is geared so that the descent is slow and percise.
Well using that idea, you could have a type of hopper which holds weights. You could detatch the hopper from the chain and slide it to the top, then re-attach the hopper to the chain and load it with heavy rocks or plates or whatever. I mean if you built it sturdy enough, how many 45lb plates could you load in that thing over an hour or 30 minutes? Quite a few i'd guess. Then over the next 24 hours the wieght filler hopper would pull down on the chain which is geared to an electric generator and electricity is produced for 24 hours.
24 hours is an arbitrary figure, Ideally you would have a series of these so there is no down time in electric production. Say you have 2 devices running, 48 hours per cycle, start one, then load another then next day, now you have 2 running, then reload the first one the next day, you would have about 30 minutes a day of running on one only. Again, I have no idea what type of electrical generation you could get from this, but I'll be doing the math on it over the next couple of months.
For the type of weight we ar talking here, say you could load a plate in 5 seconds. Thats 12 per minute. 360 for 30 minutes. Thats 16,200Lbs loaded into those hoppers. With proper gearing I think you could get a fair amount of electrical generation. I'm not saying you could go off the grid with this, but why not save money while you workout instead of paying a gym membership to do it.
Better Yet would be to have a 2 story one with a ramp in between, Then have huge hoppers with 100b sandbags. load 200 sandbags per hopper, Nice strongman type workout, cut your electric bill, win/win.