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Updated: Jul 18, 2026

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
Changes in the soleus stretch reflex at different pedaling frequencies and crank loads during pedaling
Birgit Larsen1, Michael Voight, Michael J Grey
1Center for Sensory-Motor Interaction (SMI), Dept of Health Science and Technology, Aaborg University, Aalborg, Denmark.
Abstract:
The influence of pedaling frequency and crank load on the sensitivity of the soleus short latency stretch reflex (SLR) was examined in nine healthy subjects during pedaling by the use of a custom-built robotic actuator. The SLR decreased successively in downstroke when pedaling frequency increased from 20 to 40 and 60 revolutions per minute at a constant crank load (p = .005). The SLR was unchanged at crank load increases of 2.6 or 5.1 Nm at a constant pedaling frequency (p > .05). Accordingly, it was shown that increased muscle activation level as a consequence of added crank load and increased movement speed does not increase the sensitivity of the soleus SLR.
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