Glycogen-depletion patterns with isometric and isokinetic exercise in patients after leg injury.

Abstract

1. The glycogen-depletion patterns were studies as a measure of muscle-fibre recruitment in patients after leg injuries (fractures, ligament injuries). Intermittent isometric and dynamic isokinetic knee extension were performed with 30 and 50% of the maximal isometric torque of the injured leg. In a third group isokinetic and dynamic exercise with weights were compared by using maximal effort procedures. 2. The 30% maximal voluntary contraction programme, which corresponded to 16% of maximal voluntary contraction of the non-injured leg, resulted in glycogen depletion of type I fibres, which was significant only in the isometric exercise. In the 50% maximal voluntary contraction programme (41% of maximal voluntary contraction of the non-injured leg) depletion of type II fibres dominated and was significant with isometric exercises. In the maximal effort programmes there was a significant depletion of type II fibres. 3. Subjects with a relatively large reduction in strength or a small number of type I fibres demonstrated more depletion of these fibres than other subjects. 4. In patients with moderately reduced muscle strength and muscle fibre atrophy static or dynamic exercises using at least 50% of the actual maximal voluntary contraction can thus be used to recruit and train type II fibres.

• Authors: B Hultén, P Renström, G Grimby
• Journal: Clinical science (London, England : 1979) (Clin Sci (Lond)) Vol. 61 Issue 1 Pg. 35-42 (Jul 1981) ISSN: 0143-5221 [Print] England
• PMID: 7249554 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Glycogen

Topics

• Adolescent
• Adult
• Exercise Therapy
• Female
• Glycogen (metabolism)
• Humans
• Isometric Contraction
• Leg Injuries (metabolism, therapy)
• Male
• Middle Aged
• Muscle Contraction
• Muscles (metabolism)
• Muscular Atrophy (metabolism)