Are cable machine squats easier to do than squats on a Smith machine? I'm able to do about 220 pounds on the cables, but I'm doubtful whether I'll be able to replicate the results on a Smith machine. In terms of physics, I don't really see why they would be - both are assisted to some degree, but it seems to me that cables would actually provide less assistance since they are not rigid. Any ideas?
This depends on the equipment that you are using. Smith machines friction levels vary greatly and so do cable machines (along with their weight read-outs). In general Smith squats should be harder. Also I would never substitute regular squats with these and I would never recommend anyone to do Smith machine squats unless they were advanced. It isn't a normal range of motion and can cause back, hip, knee problems.
Things to take into consideration:
- If the cable machine you use more than one pulley wheel, then your not lifting the full weight (see Wikipedia).
- Unless you manage to get the cable almost vertical, you are not displacing the weight as much on a cable machine and so not producing the same amount of work (see more wikipedia).
- Don't forget to count the weight of the bar on the Smith machine!
So you are probably right that the weight you can squat on a cable machine is likely to be more than on a Smith machine.