And the countless academic references also cited in the paper you claim supports you.
The authors
contend that the reported differences are due to less than perfect TM's, yet their own data does not support that.
FTM vs. overground measurements.
We compared the FTM signals with the established methodology of a
traditional runway-mounted force platform. We had a single subject run at 3 m/s on the FTM and across our force-platform runway. A comparison of the average values (from 10 steps) for various force magnitudes from the FTM vs. overground revealed only small differences caused by normal variation. The average peak vertical force (Fz) values were 1.78 vs. 1.83 3 BWt
for the impact peak and 2.47 vs. 2.44 3 BWt for the active peak. The average peak braking (Fy) forces were 20.30 vs. 20.35 3 BWt, and the average propulsive peaks were 0.21 vs. 0.20 3 BWt. A comparison of a
typical running stride for the FTM vs. overground force-platform records is shown in Fig. 4. The signals obtained with the FTM were
quite similar to those obtained overground. Because some stride-to-stride variability occurs, the traces were not identical.
All of these values concurred with those in the literature (21).
In other words, there is indeed a difference.
DISCUSSION
From a purely mechanical perspective, steady-speed walking or running on an adequate motorized treadmill is identical to overground walking and running; the only difference is the frame of reference for each situation (23). Locomotion on a treadmill with inadequate power or momentum (i.e., no flywheel) does indeed differ from overground locomotion.
However, on a treadmill with an adequate motor and flywheel, where the belt speed does not vary, the kinematics (21), ground-reaction forces (19), and metabolic cost (2) of locomotion are nearly indistinguishable from over-
ground locomotion. As detailed above, our motor and flywheel appear to be adequate in maintaining a constant tread speed.
Others papers report a metabolic difference of 10%. The authors did not measure that, but make statements like "appears to be" and "nearly indistinguishable from" overground locomotion.
This experiment also compares a TM and fixed platform and concluded they are not the same.
http://jap.physiology.org/content/early/2007/11/29/japplphysiol.01380.2006.full.pdf
And this is a contradiction...
In Fig. 5, we show a typical force recording from the FTM for the same subject walking at 1.25 m/s. When humans walk, both feet are on the ground for at least art of the stride cycle.
Want to tell me how the belt would not cause the runners feet to move with the belt during the time that both feet are on the belt?
The rather odd mistake of not balancing the flywheel, claiming the device is a reference and an improvement upon other designs, even though turning on the motor produces 80N readings, suggests they may be Carteers at heart.
I would consider that 80N to be evidence of a total failure.
Because Carteers have always said that a runner on a treadmill is
exactly same as a runner on the road at
wind speed. The latter is said to explain the "tailwind" that will be felt if traveling with the belt. There is no mention of a tailwind in any of the references.
Now that there are references that contradict, you and JB are now back-pedaling.
Your "equivalence" is not the guaranteed assumption derived from the very simple-minded version of Galilean Equivalence that considers only IFOR and velocity, that it is claimed to be. Opponents have always said that for that claim to hold, all forces and energies must be the same. The runner says they are not.
