Eccentric ergometry: increases in locomotor muscle size and strength at low training intensities

Abstract

Lengthening (eccentric) muscle contractions are characterized by several unusual properties that may result in unique skeletal muscle adaptations. In particular, high forces are produced with very little energy demand. Eccentrically trained muscles gain strength, but the specific nature of fiber size and composition is poorly known. This study assesses the structural and functional changes that occur to normal locomotor muscle after chronic eccentric ergometry at training intensities, measured as oxygen uptake, that do not influence the muscle when exercised concentrically. Male subjects trained on either eccentric or concentric cycle ergometers for 8 wk at a training intensity starting at 54% and ending at 65% of their peak heart rates. The isometric leg strength increased significantly in the eccentrically trained group by 36%, as did the cross-sectional area of the muscle fiber by 52%, but the muscle ultrastructure remained unchanged. There were no changes in either fiber size, composition, or isometric strength in the concentrically trained group. The responses of muscle to eccentric training appear to be similar to resistance training.

Preservation of eccentric strength in older adults: Evidence, mechanisms and implications for training and rehabilitation

“…Evidence from studies during the last decade suggest that high-intensity resistance training incorporating eccentric contractions can offer some advantages over more traditional training strategies to increase muscle strength and mass in older adults (Hortobagyi and De Vita., 2000;LaStayo et al, 2003a;Onambele et al, 2008;Reeves et al, 2009). The high metabolic efficiency (LaStayo et al, 2000) and faster adaptations observed with eccentric training (Hortobagyi et al, 1996) make it especially appealing in clinical situations after periods of immobilization or in the most debilitated old individuals (Hortobagyi and De Vita, 2000).…”

“…For example, some authors suggest that the high efficiency of eccentric contractions (i.e. intense muscle work is achieved at a lower metabolic expense) (LaStayo et al, 2000) renders them a powerful tool for restoring muscle strength in people with a limited capacity to train at high intensities such as older adults (Hortobagyi and De Vita, 2000;LaStayo et al, 2003a) and patients with chronic conditions (Dibble et al, 2006;Engardt et al, 1995;Marcus et al, 2008;Rooyackers et al, 2003). Furthermore, although the exact magnitude of this preservation has not yet been quantified, it is reasonable to surmise that this reserve of eccentric strength could be beneficial for the undertaking of resistance-training programs in people with reduced levels of muscle force (Roig et al, 2008a).…”

Η Επίδραση Της Έκκεντρης Προπόνησης Σε Δείκτες Μυϊκής Βλάβης Και Οξειδωτικού Στρες

“…Πράγματι, έχει αναφερθεί ότι η έκκεντρη μορφή άσκησης επιφέρει μεγαλύτερες αλλαγές σε σχέση με την αντίστοιχη ομόκεντρη άσκηση στην μυϊκή δύναμη (Farthing & Chilibeck, 2003;Hortobagyi, et al, 1996;LaStayo, Pierotti, Pifer, Hoppeler, & Lindstedt, 2000;Lastayo, Reich, Urquhart, Hoppeler, & Lindstedt, 1999;Paschalis, Nikolaidis, Giakas, et al, 2010;Steiner, et al, 2004). Επιπλέον, έχει αναφερθεί από έρευνες ότι η έκκεντρη άσκηση επιφέρει μεγαλύτερη μυϊκή υπερτροφία σε σχέση με την ομόκεντρη άσκηση (Farthing & Chilibeck, 2003;LaStayo, et al, 2000).…”

“…Επιπλέον, έχει αναφερθεί από έρευνες ότι η έκκεντρη άσκηση επιφέρει μεγαλύτερη μυϊκή υπερτροφία σε σχέση με την ομόκεντρη άσκηση (Farthing & Chilibeck, 2003;LaStayo, et al, 2000).…”

“…Πιο συγκεκριμένα, η έκκεντρη προπόνηση αύξησε την ενεργειακή δαπάνη ηρεμίας, αύξησε την οξείδωση λιπιδίων και βελτίωσε το λιπιδαιμικό προφίλ σε μεγαλύτερο βαθμό σε σχέση με την αντίστοιχη ομόκεντρη προπόνηση. Επιπλέον, αύξησε περισσότερο και τη μέγιστη ισομετρική ροπή σε σχέση με την ομόκεντρη προπόνηση, γεγονός που έχει αναφερθεί και από άλλες έρευνες (Farthing & Chilibeck, 2003;Hortobagyi, et al, 1996;LaStayo, et al, 2000).…”