ALEXANDRIA, Va., March 17 -- United States Patent no. 12,576,311, issued on March 17, was assigned to Tonal Systems Inc. (San Francisco).

"Collaborative exercise" was invented by David Azaria (San Francisco), Sumner Browning Paine (San Francisco), Justin Ziccardi (San Francisco) and Sarah Wilson Lewis (San Francisco).

According to the abstract* released by the U.S. Patent & Trademark Office: "Load data is received from a first exercise machine. An updated resistance for a second exercise machine is determined based on the load data received from the first exercise machine. A request to update a resistance associated with the second exercise machine is provided to the second exercise machine. The second exercise machine updates the resista...