Affiliations: [a] Division of Physical Therapy, Department of Orthopaedics and Rehabilitation, School of Medicine, University of Miami, 5915 Ponce de Leon Blv., Plumer Building, 5th Floor, Coral Gables, FL, 33146 USA | [b] Department of Physical Therapy, College of Staten Island, CUNY, Staten Island, NY, USA | [c] Occupational Industrial Orthopaedic Center, Hospital for Joint Diseases, New York University, 63 Downing St. New York, NY 10014, USA
Note: [*] Corresponding author.
Abstract: This study examined the effect of previous contraction condition on subsequent eccentric power production in the elbow flexor muscles in 20 healthy volunteers (10 males, 10 females). Power production was determined during constant velocity eccentric loading at 60°/s when preceded by: condition 1 passive elbow flexion; condition 2 maximal concentric contraction of the elbow flexor muscles; or condition 3 maximal isometric contraction of the elbow flexors. Comparison of eccentric power production under the different conditions was conducted using a repeated measures ANOVA. Results indicated that a continuum exists between conditions such that eccentric power production when preceded by condition 1 is < power production when preceded by condition 2, is < power production when preceded by condition 3. Implications are that contraction condition previous to eccentric loading allows various levels of tension transfer in the series elastic and the contractile components producing different levels of torque during the ensuing eccentric loading of the muscle. Techniques utilizing combinations of movement to enhancing muscle contraction should be examined critically with regard to order of movement and contraction conditions.
