These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Segmental reflex organization in endurance-trained athletes and untrained subjects.
    Author: Koceja DM, Kamen G.
    Journal: Med Sci Sports Exerc; 1992 Feb; 24(2):235-41. PubMed ID: 1549013.
    Abstract:
    In an effort to investigate the effects of training on spinal reflex pathways in humans, we measured the isometric force-time curve of the patellar (PTR) and Achilles (ATR) tendon-tap reflex in 12 endurance-trained (ET) athletes and 12 control (C) subjects. We also conditioned the tendon jerk with a contralateral or ipsilateral tendon-tap stimulus, to ascertain the effects of segmental inputs on crossed-spinal reflex activity. The conditioning stimulus preceded the test reflex by 25, 40, 55, 70, 85, 100, 115, 130, or 145 ms. The results demonstrated significant differences in control reflexes and conditioned reflexes between the two groups. A contralateral patellar tendon-tap produced a significantly greater excitatory effect to the contralateral quadriceps motoneurons for the ET group, whereas a contra- or ipsilateral conditioning caused a significantly greater inhibitory effect to the triceps surae motoneurons for the ET athletes. These results demonstrate that motoneuron excitability changes can be produced as a result of ipsi- and contralateral segmental inputs, and raise the possibility that trained athletes demonstrate different reflex recovery profiles. Several neurophysiological mechanisms are proposed to contribute to these changes.
    [Abstract] [Full Text] [Related] [New Search]