Muscle Pain Markers Induced by Eccentric Contraction
. [PGE.sub.2] increases in skeletal muscle during dynamic exercise, but it does not increase during static exercise .
The greater force production with less energy involvement would produce less stress on muscles, thereby reducing nutrient and oxygen requirement during an eccentric contraction
as compared to a concentric contraction.
When entering the mid-stance phase, the plantar flexors were transformed from eccentric contraction
(doing negative work) into concentric contraction (doing positive work) and pushed the body into the swing phase.
These periods of high torque and power absorption occur when the knee is flexing; thus, a large, eccentric contraction
of knee extensors is required to prevent leg buckling.
In a research on eccentric and concentric contraction groups, increased CK was observed only in the eccentric contraction
of the quadriceps (Q) muscles during landings is vital for energy absorption (4, 19, 20); however, large Q forces have the potential to stress and increase injury risk to knee joint ligaments.
A hamstring injury most commonly occurs during an eccentric contraction
. This is simply an eccentric contraction
, the muscles fibers contracting while being lengthened (as a pose to a concentric contraction when the muscle fibers shorten when contracting).
Biomechanical assessment shows that LE is primarily caused by excessive ECRB eccentric contraction
causing a microtraumatic tear in the common extensor tendon origin (Figure 2).
A rupture occurs during eccentric contraction
- when the calf muscle contracts but the toes are curling up.
(1) These injuries usually occur in males in their fourth to sixth decade of life and are the result of a sudden, forceful eccentric contraction
of the biceps muscle.
After a slight pause with continued tension, the spotter pulls back slowly--again, with great care--while the lifter gives enough resistance to ensure an even, gradual eccentric contraction
to the starting position.
Activities that require muscles to forcefully contract while they are lengthening such as running downhill, going downstairs, or lowering a weight (eccentric contraction
) seem to result in the most pain.