title: Leg strength, preferred walking speed, and daily step activity in adults with incomplete spinal cord injuries.
abstract: BACKGROUND
  The reduction in physical activity that accompanies spinal cord injury (SCI) contributes to the development of secondary health concerns. Research has explored potential strategies to enhance the recovery of walking and lessen the impact of physical disability following SCI, but further work is needed to identify determinants of community walking activity in this population.
  
  
  OBJECTIVE
  To quantify relationships among lower extremity strength (LES), preferred walking speed (PWS), and daily step activity (DSA) in adults with incomplete SCI (iSCI) and determine the extent to which LES and PWS predict DSA in persons with iSCI.
  
  
  METHODS
  Participants were 21 adults (age range, 21 to 62 years; AIS levels C and D) with iSCI. Maximal values of hip abduction, flexion, and extension, knee flexion and extension, and ankle dorsiflexion and plantar flexion were measured using handheld dynamometry and were summed to determine LES. PWS was calculated using a photoelectric cell-based timing system, and participants were fitted with activity monitors to measure DSA in a natural setting.
  
  
  RESULTS
  Statistically significant (P <; .05) correlations of moderate to high magnitude (.74 to .87) were observed among LES, PWS, and DSA. Multiple regression analysis revealed that LES and PWS accounted for 83% (adjusted R2) of the variation in DSA (P <; .001).
  
  
  CONCLUSIONS
  A significant proportion of the explained variance in DSA can be predicted from knowledge of LES and PWS in adults with iSCI. These findings suggest that future efforts to improve community walking behavior following SCI should be directed toward increasing LES and PWS.
authors.affiliation: Department of Health and Human Performance, Middle Tennessee State University , Murfreesboro, Tennessee.
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Stevens
authors.forename: Dana K
authors.initials: DK
authors.lastname: Fuller
authors.forename: Don W
authors.initials: DW
authors.lastname: Morgan
keywords: daily step activity; incomplete spinal cord injury; lower extremity strength; walking; walking speed