Strength enhancement with limited range closed kinetic chain isokinetic exercise of the upper extremity

Background: Specificity plays an important role in the design of strength training protocols. One of the paramount factors is the range of motion (ROM). Objective: To explore limited range of motion (ROM) strength training using a closed chain upper extremity push pull motion. Range specific effects and transferability (strength gains outside the trained ROM) were investigated. Method: 45 healthy women (18-50 ± 4.2) randomly assigned to one of three groups: Full ROM group, Limited ROM group, Control group. Training and testing were conducted using a closed chain attachment of an isokinetic dynamometer, at a constant linear velocity of 12.22 cm/s (corresponding to the dynamometer angular velocity of 60°/sec) and a second condition of 36.67 cm/s (corresponding to the dynamometer angular velocity of 180°/sec). Training lasted 6 weeks X 2 days per week, through either full or limited ROM, representing a middle segment of the linear displacement of the handle through the full ROM. Peak force and work data were evaluated. Results: Significant gains in peak force and work values at full ROM and all sub ranges were noted for both training groups. Transferability of strength was demonstrated for limited ROM training, whereas specificity could be demonstrated only under the condition of range X velocity interaction. Conclusion: Our findings support the use of limited ROM training in the upper extremity and are in agreement with previous data regarding the knee extensors. Limited ROM training may be used early on in upper extremity rehabilitation. Particularly, the suggested protocol may be safely applied to scapular rehabilitation.