Original article
Is Stair Climb Power a Clinically Relevant Measure of Leg Power Impairments in At-Risk Older Adults?

https://doi.org/10.1016/j.apmr.2007.02.004Get rights and content

Abstract

Bean JF, Kiely DK, LaRose S, Alian J, Frontera WR. Is stair climb power a clinically relevant measure of leg power impairments in at-risk older adults?

Objective

To test the clinical relevance of the stair climb power test (SCPT) as a measure of leg power impairments in mobility-limited older adults.

Design

Cross-sectional analysis of baseline data from participants within a randomized controlled trial.

Setting

Rehabilitation research gym.

Participants

Community-dwelling older adults (N=138; mean age, 75.4y) with mobility limitations as defined by the Short Physical Performance Battery (SPPB).

Interventions

Not applicable.

Main Outcome Measures

Leg power measures included the SCPT and double leg press power measured at 40% (DLP40) and 70% (DLP70) of the 1 repetition maximum. Mobility performance tests included the SPPB and its 3 components: gait speed, chair stand time, and standing balance.

Results

Stair climb power per kilogram (SCP/kg) had correlations of moderate strength (r=.47, r=.52) with DLP40/kg and DLP70/kg, respectively. All 3 leg power measures correlated with each of the mobility performance measures with the exception of DLP40/kg (r=.11, P=.27) and DLP70/kg (r=.11, P=.18) with standing balance. Magnitudes of association, as described by the Pearson correlation coefficient, did not differ substantively among the separate power measures as they related to SPPB performance overall. Separate adjusted multivariate models evaluating the relationship between leg power and SPPB performance were all statistically significant and described equivalent amounts of the total variance (R2) in SPPB performance (SCP/kg, R2=.30; DLP40, R2=.32; DLP70, R2=.31). Analyses of the components of the SPPB show that the SCPT had stronger associations than the other leg power impairment measures with models predicting chair stand (SCP/kg, R2=.25; DLP40, R2=.12; DLP70, R2=.13), whereas both types of leg press power testing had stronger associations with models predicting gait speed (SCP/kg, R2=.16; DLP40, R2=.34; DLP70, R2=.34). Stair climb power was the only power measure that was a significant component of models predicting standing balance (SCP/kg R2=.20).

Conclusions

The SCPT is a clinically relevant measure of leg power impairments. It is associated with more complex modes of testing leg power impairments and is meaningfully associated with mobility performance, making it suitable for clinical settings in which impairment-mobility relationships are of interest.

Section snippets

Methods

This study was a cross-sectional analysis of baseline data from a randomized controlled trial of exercise among mobility-limited older adults.

Results

Participants had a mean age of 75.4 years and were predominately women (69%), predominantly white (85%) (15% black), and overweight, with a mean body mass index of 27.5kg/cm2 (table 1). On average, participants reported 5.6 chronic medical conditions and were prescribed 4.3 medications. Participants had a mean SPPB of 8.7, which has been characterized as mobility limitations of moderate severity.25 Consistent with this, performance measures included the following mean values: gait speed of

Discussion

Our investigation is the first to attempt to formally evaluate the SCPT as a potential measure of lower-extremity power and a predictor of important outcomes of mobility performance. The major finding of our study is that models using the SCPT predict approximately one third of SPPB performance, which is comparable with that predicted by leg power measured using pneumatic isotonic resistance machines. In addressing the 3 components of the SPPB, compared with both DLP40 and DLP70, the SCPT had a

Conclusions

Our study has shown that the associations between the SCPT and the SPPB are sufficiently strong to consider the SCPT a relevant clinical measure of leg muscle power impairments. The true test of the feasibility of the SCPT as an impairment measure would be the evaluation of its use within clinical settings that use mobility performance testing as a means of screening for those at risk for disability. Most clinicians caring for older adults do not have access to lab-based power measures. We

References (32)

  • M.F. Folstein et al.

    “Mini-mental state.”A practical method for grading the cognitive state of patients for the clinician

    Psychiatr Res

    (1975)
  • W.J. Evans

    Exercise strategies should be designed to increase muscle power

    J Gerontol A Biol Sci Med Sci

    (2000)
  • J. Bean et al.

    The relationship between leg power and physical performance in mobility-limited elders

    J Am Geriatr Soc

    (2002)
  • J.F. Bean et al.

    A comparison of leg power and leg strength within the InCHIANTI Study: which influences mobility more?

    J Gerontol A Biol Sci Med Sci

    (2003)
  • Y. Liao et al.

    Recent changes in the health status of the older U.S. population: findings from the 1984 and 1994 supplement on aging

    J Am Geriatr Soc

    (2001)
  • S. Studenski et al.

    Physical performance measures in the clinical setting

    J Am Geriatr Soc

    (2003)
  • J.M. Guralnik et al.

    Lower extremity function and subsequent disability: consistency across studies, predictive models, and value of gait speed alone compared with the Short Physical Performance Battery

    J Gerontol A Biol Sci Med Sci

    (2000)
  • J.M. Guralnik et al.

    Lower extremity function over age of 70 years as a predictor of subsequent disability

    N Engl J Med

    (1995)
  • C. Cavazzini et al.

    Screening for poor performance of lower extremity in primary care: the Camucia Project

    Aging Clin Exp Res

    (2004)
  • K. Hakkinen et al.

    Changes in electromyographic activity, muscle fibre and force production characteristics during heavy resistance/power strength training in middle-aged and older men and women

    Acta Physiol Scand

    (2001)
  • T.A. Miszko et al.

    Effect of strength and power training on physical function in community-dwelling older adults

    J Gerontol A Biol Sci Med Sci

    (2003)
  • R.A. Fielding et al.

    High velocity power training increases skeletal muscle strength and power in community-dwelling older women

    J Am Geriatr Soc

    (2002)
  • J. Bean et al.

    Weighted stair climbing in mobility limited elders: a pilot study

    J Am Geriatr Soc

    (2002)
  • J.F. Bean et al.

    Increased Velocity Exercise Specific to Task (InVEST) training: a pilot study exploring effects on leg power, balance, and mobility in community-dwelling older women

    J Am Geriatr Soc

    (2004)
  • E.J. Bassey et al.

    A new method for measuring power output in a single leg extension: feasibility, reliability, and validity

    Eur J Appl Physiol

    (1990)
  • R.H. Whipple et al.

    The relationship of knee and ankle weakness to falls in nursing home residents: an isokinetic study

    J Am Geriatr

    (1987)
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