Dataset Information

Muscle Performance Changes with Age in Active Women.

ABSTRACT: The purpose of this study was to examine age-related differences in muscle performance in women divided into young (YW, 20-39 years, n = 29) middle-aged (MAW, 40-59 years, n = 33), and older (OW, ≥60 years, n = 40) age groups. Hand grip strength, vertical jump performance, and knee extensor (KE) strength (0 deg/s, 60 deg/s, and 240 deg/s), speed of movement (SoM; at 1 Nm, 20%, 40%, and 60% isometric strength), and endurance (30-repetition test at 60 degs/s and 240 deg/s) were assessed. Computed tomography-acquired muscle cross-sectional area (mCSA) was measured and included to determine specific strength (KE strength/mCSA). Hand grip strength was similar across groups, while jump performance declined with age (YW and MAW > OW, p < 0.001). KE strength declined significantly with age (all conditions p < 0.01), while specific strength was similar across groups. SoM was significantly higher for YW and MAW compared to OW (both p < 0.01). An age × velocity interaction revealed YW KE endurance was similar between conditions, whereas MAW and OW displayed significantly better endurance during the 60 deg/s condition. OW displayed impaired KE endurance at 240 deg/s (vs. YW and MAW, p < 0.01) but improved at 60 deg/s (vs. YW, p < 0.01). Dynamic torque decline increased with age (YW < OW, p = 0.03) and was associated with intramuscular adipose tissue (r = 0.21, p = 0.04). Performance declines were most evident among OW, but few performance deficits had emerged in MAW. Interestingly, strength declines disappeared after normalizing to mCSA and endurance appears to be velocity-dependent.

SUBMITTER: Miller RM

PROVIDER: S-EPMC8122865 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Muscle Performance Changes with Age in Active Women.

Miller Ryan M RM Freitas Eduardo D S EDS Heishman Aaron D AD Peak Keldon M KM Buchanan Samuel R SR Kellawan J Mikhail JM Pereira Hugo M HM Bemben Debra A DA Bemben Michael G MG

International journal of environmental research and public health 20210423 9

The purpose of this study was to examine age-related differences in muscle performance in women divided into young (YW, 20-39 years, <i>n</i> = 29) middle-aged (MAW, 40-59 years, <i>n</i> = 33), and older (OW, ≥60 years, <i>n</i> = 40) age groups.<h4>Methods</h4>Hand grip strength, vertical jump performance, and knee extensor (KE) strength (0 deg/s, 60 deg/s, and 240 deg/s), speed of movement (SoM; at 1 Nm, 20%, 40%, and 60% isometric strength), and endurance (30-repetition test at 60 degs/s and ...[more]

PMID: 33922474

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Dataset Information

Muscle Performance Changes with Age in Active Women.

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Muscle Performance Changes with Age in Active Women.

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