TY - GEN
T1 - Comparison of biomechanical and anatomical effects following eccentric and concentric exertions
AU - Chourasia, Amrish O.
AU - Sesto, Mary E.
AU - Jung, Youngkyoo
AU - Howery, Robert S.
AU - Radwin, Robert G.
PY - 2005/12/1
Y1 - 2005/12/1
N2 - Work place exertions may include muscle shortening (concentric) or muscle lengthening (eccentric) contractions. This study investigates the upper limb mechanical properties and magnetic resonance images (MRI) of the involved muscles following submaximal eccentric and concentric exertions. Twelve participants were randomly assigned to perform at 30° per second eccentric or concentric forearm supination exertions at 50% isometric maximum voluntary contraction (MVC) for 30 minutes. Measurement of mechanical stiffness, isometric MVC, localized discomfort and MRI supinator: extensor signal intensity ratio was done before, immediately after, 1 hour after and 24 hours after the bout of exercise. A 53% average decrease in mechanical stiffness after 1 hour was observed for the eccentric group (p< 0.05) compared to a 1% average decrease for the concentric group (p> 0.05). Edema, indicative of swelling, was observed 24 hrs after exercise, with an average increase in the MRI supinator: extensor signal intensity ratio of 36% for the eccentric group and less than 10% for the concentric group (p<0.05).
AB - Work place exertions may include muscle shortening (concentric) or muscle lengthening (eccentric) contractions. This study investigates the upper limb mechanical properties and magnetic resonance images (MRI) of the involved muscles following submaximal eccentric and concentric exertions. Twelve participants were randomly assigned to perform at 30° per second eccentric or concentric forearm supination exertions at 50% isometric maximum voluntary contraction (MVC) for 30 minutes. Measurement of mechanical stiffness, isometric MVC, localized discomfort and MRI supinator: extensor signal intensity ratio was done before, immediately after, 1 hour after and 24 hours after the bout of exercise. A 53% average decrease in mechanical stiffness after 1 hour was observed for the eccentric group (p< 0.05) compared to a 1% average decrease for the concentric group (p> 0.05). Edema, indicative of swelling, was observed 24 hrs after exercise, with an average increase in the MRI supinator: extensor signal intensity ratio of 36% for the eccentric group and less than 10% for the concentric group (p<0.05).
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M3 - Conference contribution
AN - SCOPUS:44349094868
SN - 094528926X
SN - 9780945289265
T3 - Proceedings of the Human Factors and Ergonomics Society
SP - 1287
EP - 1291
BT - Proceedings of the Human Factors and Ergonomics Society 49th Annual Meeting, HFES 2005
T2 - 49th Annual Meeting of the Human Factors and Ergonomics Society, HFES 2005
Y2 - 26 September 2005 through 30 September 2005
ER -