I am an ignoramous when it comes to understanding electricity. I am thinking about getting 2 110v treadmills (one for me and my wife) for our basement and I am concerned about the ability of the wiring to handle the load from them. The basement seems to be wired with two different lines and each has a 15 amp fuse. If I plug each mill into a different line, will it each line be able to handle the load or do I have to change the wiring?
Each TM needs to be on its own circuit if you intend to use them at the same time. If those lines go back to your fuse box and each feeds its own separate 15A fuse, you should be OK plugging one TM into each line. A 20A breaker would be better as you'd then have a little headroom for other items on the same line (fan, stereo, TV, lights etc.) while running. Some of the larger TMs aren't going to give you much headroom for auxiliary gear when the TM's cranking away.
Basically, the greatest demand for current will occur when you first turn the unit on and it comes up to speed. Steady state current draw will back off. How old is the wiring? Do you really have fuses? If it's really old you might want to have someone check it. (I am reminded of a friend whose old house had open wire with ceramic knobs and the cloth insulation was so fragile you couldn't even breathe on it.)