Exercise treadmills
Over 100 years ago, there was an US patent of treadmill "training machine" (#1,064,968) issued on June 17, 1913.[8]
The forerunner of exercise treadmills was designed to diagnose heart and lung disease, and was invented by Dr. Robert Bruce and Wayne Quinton at the University of Washington in 1952.[9][10] Dr. Kenneth H. Cooper's research on the benefits of aerobic exercise, published in 1968, provided a medical argument to support the commercial development of the home treadmill and exercise bike.