Comparison of Handgrip and Leg Extension Strength in Predicting Slow Gait Speed in Older Adults

M.S. Fragala, D.E. Alley, M.D. Shardell, T.B. Harris, R.R. McLean, D.P. Kiel, P.M. Cawthon, T.T.L. Dam, L. Ferrucci, J.M. Guralnik, S.B. Kritchevsky, M.T. Vassileva, V. Gudnason, G. Eiriksdottir, A. Koster, A. Newman, K. Siggeirsdottir, S. Satterfield, S.A. Studenski, A.M. Kenny

J Am Geriatr Soc. 2016;64:144–150

This study aimed at comparing the power of handgrip strength with that of leg extension strength to predict slow walking.  

For this purpose leg strength, handgrip strength, and gait speed of 6,766 men and women, aged 67 to 93, were measured. Strength cutpoints associated with slow gait speed were developed using classification and regression tree analyses and compared using ordinary least squares regression models.

The cutpoints of lower extremity strength associated with slow gait speed were 154.6 N-m in men and 89.9 N-m in women for isometric leg extension strength and 94.5 N-m in men and 62.3 N-m in women for isokinetic leg extension strength. Weakness defined according to handgrip strength (odds ratios (OR) = 1.99 to 4.33, c-statistics = 0.53 to 0.67) or leg strength (ORs = 2.52 to 5.77; c-statistics = 0.61 to 0.66) was strongly related to odds of slow gait speed. Lower extremity strength contributed 1% to 16% of the variance and handgrip strength contributed 3% to 17% of the variance in the prediction of gait speed depending on sex and mode of strength assessment.

 

Comment: Handgrip strength may be an adequate measure to predict physical function in clinical settings. These date provide support for selecting grip strength as a measure of strength in developing a clinical definition of sarcopenia. Leg extension strength is only a slightly better predictor of slow gait speed. Thus, results support performing a preliminary strength assessment using the handgrip strength dynamometer, although more-intricate measures of muscle-specific lower extremity strength may be used for follow-up testing. Alternatively, because gait measures are relatively easy to perform in the office setting, and because strength measures explain only a small percentage of the variance in gait speed, it may be more useful to measure gait speed directly. Slow gait speed might then prompt a search for contributing causes such as muscle weakness. Nevertheless, these results will be useful in the development of consensus diagnostic criteria for sarcopenia from a muscle specific perspective.