| Split belt treadmills were originally designed to help | | | | Patients work on leg muscle development and range |
| stroke victims learn to walk again. They were | | | | of motion, swing phase duration of the leg and foot |
| introduced as part of the rehab process after | | | | clearance. |
| researchers discovered that the body contained | | | | Force Sensing Treadmill (One Belt in Front of |
| separate nerve networks directing the movements | | | | Another) |
| of each leg. There is another device researchers are | | | | Another innovative design is the force sensing |
| using to study and improve the human gait and that's | | | | treadmill which is used in scientific studies as a gait |
| called the force sensing treadmill. Let's take a quick | | | | analysis system to measure the force of footfalls |
| look at each: | | | | separately and accurately. Developed for the U.S. |
| Split Belt (Side-by-Side) | | | | Army at its Research Institute of Environmental |
| Scientists have found that our legs can be taught to | | | | Medicine, researchers can determine the pressure |
| function almost independently of each other. This | | | | each foot is exerting while walking or running. |
| discovery has lead to putting test subjects on split | | | | The Force Sensing Treadmill, built by Advanced |
| belt treadmills in which one side of the belt moves at | | | | Mechanical Technology Inc. of Watertown, Mass., |
| a different speed than the other. Or, one side can | | | | positions two belts on the front and back of the |
| move one foot back while the other moves forward. | | | | deck rather than side by side. Again, it resembles a |
| Using this machine, stroke patients, and others with | | | | regular treadmill but if you look closely it has a break |
| incomplete spinal cord or brain injuries are having their | | | | between the two belts. Each force platform is |
| brains "re-wire" themselves to mimic normal leg | | | | attached to a common chassis. The belts move |
| control. | | | | around their perspective rollers at the same speed |
| Decades ago, doctors thought that the brain could | | | | while sensors collect data when each foot strikes the |
| not learn again once function was lost. Yet recent | | | | belt during a walk or run. Like a regular treadmill, |
| research has proven that the brain has the ability to | | | | speeds up to 11 mph are possible and it even has an |
| acquire new skills and knowledge through repetition | | | | incline ramp up to 25 percent. |
| and instruction. Doctors have now learned that the | | | | Now that the torque of the footfalls can be |
| right circuitry for walking still may exist in the | | | | measured and analyzed separately, researchers are |
| damaged brains of many patients. This dormant | | | | able to study the gait biomechanics. The subject |
| system can be challenged by movements of the legs | | | | walks normally on the belts and would feel no |
| on the split belt treadmills to reawaken the old gait. | | | | difference from walking on a regular treadmill. The |
| How it works: Your brain constantly and automatically | | | | force sensing treadmill then records 3-D forces and |
| tries to adjust your skeletal structure to keep you | | | | torques on each foot during the durations when |
| upright. The ability to teach the brain to learn through | | | | either foot is in contact with the belt. Since both feet |
| repeating motor skills is the phenomena known as | | | | never strike the same belt at the same time, the |
| neuroplasticity. In this case, it's related to reorganizing | | | | force strike can be measured more accurately. |
| neuro pathways to achieve lower body movement. | | | | Thousands of data points per second are recorded |
| The central nervous system is retrained to adopt | | | | by the platform as well as video cameras for analysis. |
| walking motions - at least during the time spent on | | | | The split belt treadmills and the specialized force |
| the treadmill and for a short time afterward. | | | | sensing treadmill are at the forefront of biomechanical |
| Treadmills have long been used in therapy and | | | | technology. Relearning coordination and advancing |
| conditioning of rehab patients. Relearning coordination | | | | locomotor skills are just the beginning of what these |
| as a result of a few sessions with these split belt | | | | researchers hope to achieve with these machines. |
| treadmills are at the heart of the methodology. | | | | |