Date Published: October 23, 2017
Publisher: Springer International Publishing
Author(s): Charlotte Buckley, Maria Stokes, Dinesh Samuel.
Grip strength is a reliable predictor of whole body strength in older adults, but muscle characteristics of people with different activity levels have not been studied previously. The present study examined the relationship between grip strength (GS), quadriceps peak torque (QPT), functional endurance, and health-related quality of life (HRQoL) in older female golfers.
Twenty-nine healthy female golfers (mean age 69.1 years, SD 3.4) participated. The ISOCOM and JAMAR dynamometers were used to assess QPT and GS, respectively. Functional endurance tests included 1-min sit-to-stand test (1MSTS), 30-s wall press (30SWP), and 2-min stair climb (2MSC). HRQol was assessed using the SF-36 questionnaire.
Mean GS and QPT were 27.5 ± 4 kg/f and 103.7 ± 25.1 N m, respectively. Mean scores for the 1MSTS, 30SWP, and 2MSC were 31 ± 7.7, 17.4 ± 3.5, and 237.5 ± 48.6 repetitions, respectively. GS was moderately correlated with QPT (r = 0.44), 1MSTS (r = 0.36), and 2MSC (r = 0.36), but had weak correlation with 30SWP (r = 0.003). Moderate correlation was observed between quadriceps peak torque and the 1MSTS (r = 0.50; p = 0.01), 2MSC (r = 0.44; p = 0.02) and 30SWP (r = 0.33). 30SWP and 2MSC had moderate correlations with PF r = 0.41 (p = 0.03) and r = 0.61 (p < 0.0005) and general physical well-being r = 0.47 (p = 0.01) and r = 0.39 (p = 0.04), respectively. Quadriceps strength was more closely associated with functional endurance than grip strength. A single strength measure may not reflect overall muscle characteristics in active older females, and hence, assessment of both upper and lower limb strengths may be appropriate.
The population is ageing and the proportion of people aged over 65 years is projected to increase from 16% of the total population to 24% by 2051 . Skeletal muscle mass depletes with age in both men and women . By the age of 60, a typical person would have already lost 25% of their youth peak strength . Disuse may be an important cause of muscle atrophy and weakness, rather than ageing alone [4–6], and functional loss may be attenuated by frequent physical activity [7, 8]. The promotion of regular exercise is important for encouraging active ageing to maintain general health. This calls for effective ways to measure muscle strength and endurance in active older individuals. There is also a need to characterise musculoskeletal function in active older female golfers using non-invasive measures, which are easily conducted and reproducible.
A summary of grip and quadriceps strength and functional endurance tests can be seen in Table 2. Pearson’s correlation presented in Table 3 showed moderate association between quadriceps peak torque and grip strength in active older females (r = 0.44; p = 0.02).
The present study provides novel data on the relationships between grip strength, quadriceps strength, functional endurance, and HRQoL in active older female golfers between the ages of 65 and 80. The previous literature highlights that grip strength is well correlated with quadriceps strength in healthy adults , confirming that grip strength can be used as a surrogate for quadriceps strength. Handgrip measurements have been widely used in clinical practice to establish sarcopenia over other lower limb measurements . The key reason being, measuring grip strength by handgrip dynamometry is easy to administer, accessible, and cost-effective. Grip strength is associated with a number of health parameters, as well as strength, which suggests an interchangeability of upper and lower limb measurements .
The main limitation of this study was the small sample size. More robust results may have been found if a larger sample was utilized. Another limitation was that the units of measurement used in this study for handgrip and quadriceps strength were not the same; therefore, a ratio of handgrip to quadriceps strength could not be calculated. Quadriceps peak torque measured on the dynamometer may not be used in the community, and therefore, this measurement is less reproducible in a community setting. The 6-min walk test is a useful measure of endurance and could be considered for future studies. The order of testing was not randomised. However, in the present study, this was not possible due to the requirements of the other studies being conducted. The lack of data on muscle mass is recognised as a limitation of this study, although muscle strength is known to be highly correlated with muscle size . The absence of a comparative group of sedentary older adults is another important limitation, which should be addressed in future studies. The cross-sectional nature of this study does not enable the cause and effect to be studied but indicates measures that could be used in a prospective study in novice golfers compared with non-golfing controls.
Functional endurance was more closely related to quadriceps strength than grip strength. It is recommended that when assessing strength and endurance in an active older population a whole body approach to testing may be taken. By assessing quadriceps strength, handgrip strength, and functional endurance, more specific detection of upper and lower extremity strength decline can be achieved. This allows for specific muscle groups to be targeted that may be declining in strength. In the present study, the musculoskeletal function in active older female golfers was characterised. Playing golf after the age of 65 years might be valuable in preserving strength, endurance, and health-related quality of life in active older females.