Running Economy and joint stiffness

Well, this is possible, but so is the existence of aliens we suppose. But this article MAY have more of a dialogue on the faulty strategies of the long and short flexors and extensors as a combined strategy for gait stability and purchase of the foot on the ground. Postural sway may necessitate a toe clench strategy, for example, which could force a toe hammer strategy and thus more long flexor/short extensor tone of the digit muscles. This in itself could alter MPJ passive stiffness over time and may not correlate with any of the study findings below.

Findings by Hok Sum Man et al:
MPJ passive stiffness in sitting position is highly correlated to leg stiffness in running.
•MPJ passive stiffness in sitting position is moderately correlate to vertical stiffness in running.
•MPJ passive stiffness in either sitting and standing position is not correlated to running efficiency.

http://www.gaitposture.com/article/S0966-6362(16)30123-0/abstract?platform=hootsuite