ISCD, 2012;
Jumping Mechanography and Classic Muscle Function Tests Effects of Age and Gender
Year: 2012
Fidler E, Buehring B, Libber J, Checovich M, Krueger D, Binkley N
University of Wisconsin Osteoporosis Clinical Center and Research Program, Madison , WI
Abstract
Background:Sarcopenia is a risk factor for falls and fractures. As muscle function predicts disability and mortality better than muscle mass, recent consensus sarcopenia definitions include measures of both muscle mass and function. Clinical trials of sarcopenia prevention/treatment require sensitive quantitative tools to evaluate muscle function; jumping mechanography (JM) is likely to be one such tool. However, prior to use of JM in prospective trials, it is necessary to evaluate comparability with existing functional tests in
men and women. As such, the purpose of this study was to evaluate the impact of gender and age on classic muscle function tests and JM. We hypothesized that JM parameters of muscle function would be lower in older adults and in women and correlate with classic tests.
Methods:
Community dwelling individuals age 70+ performed muscle function tests including JM, the short physical performance battery (SPPB) and grip strength. JM measures force and calculates body weight corrected peak power and jump height. Appendicular
lean mass (ALM) was measured using a GE Lunar iDXA. T-tests and multivariate regression analyses were performed.
Results:
Participants included 49 females and 48 males (mean age 80.7 years, range 70 – 95). Gender differences were present with men having higher grip strength [mean (SD) 32.4 (7.4) vs. 18.3 (4.7) kg], jump height [mean (SD) 20.0 (5.2) vs. 15.2 (4.8) cm], jump power
[mean (SD) 22.7 (4.3) vs. 18.4 (4.4) W/kg] and ALM/ht2 [mean (SD) 7.75 (0.9) vs. 6.19 (0.8) kg/m2; all comparisons p<0.0001]. Age was negatively associated with performance in grip strength, total SPPB, jump height and jump power (p<0.05) with a trend in timed chair
rise and gait speed (p=0.06). No age correlation was observed in ALM/ht2.
Conclusion:
In this cohort, men performed better than women in tests of muscle strength, but not in tests assessing speed and balance. Muscle function was poorer in older adults irrespective of gender for most tests. JM parameters may integrate both strength and power. To improve utility of JM as a sarcopenia research tool, it would be helpful to establish normative ranges.
GID: 3005; Last update: 22.06.2012
