In an eccentric exercise the muscle contracts from a relatively shortened position to a longer position Performed either with gravity or a controlled release of a load/resistance Inner range to outer range.
Both concentric and eccentric exercises have distinct importance in rehabilitation and conditioning programs. Concentric muscle contractions accelerate body segments, whereas eccentric contractions decelerate body segments (e.g., during sudden changes of direction or momentum).
Eccentric contractions also act as a source of shock absorption during high-impact activities. A combination of concentric and eccentric muscle action is evident in numerous tasks of daily living, for example walking up and down inclines, ascending and descending stairs, rising from a chair and sitting back down, or picking up or setting down an object.
Eccentric training is considered an essential component of rehabilitation programs following musculoskeletal injury or surgery and in conditioning programs to reduce the risk of injury or reinjury associated with activities that include high-intensity deceleration, quick changes of direction, or repetitive eccentric muscle contractions.
Eccentric training also is thought to improve sport-related physical performance. The features of eccentric exercise when compared with concentric exercise are, on the positive side, that it is mechanically more efficient and metabolically more efficient, but, on the negative side, it is less resistant to fatigue and may result in DOMS (Delayed-onset muscle soreness (DOMS) a dull, or frequently more severe, aching sensation that follows unaccustomed muscular exertion).
The patient flexes elbows up to 100 degrees and then slowly extends against resistance thus performing a eccentric biceps curl.