Sarcopenia Is Negatively Related to High Gravitational Impacts Achieved From Day-to-day Physical Activity

Abstract

BackgroundSarcopenia has been associated with reduced physical activity (PA). We aimed to determine if sarcopenia, and specific components of muscle size, function, and physical performance, are associated with high impacts achieved during habitual PA, as these are related to bone strength in community-dwelling older women.MethodsParticipants were older women from the Cohort of Skeletal Health in Bristol and Avon. We defined sarcopenia using the EWGSOP criteria. Lower limb peak muscle power and force were assessed using Jumping Mechanography (JM). High vertical impacts were assessed by tri-axial accelerometry (at least 1.5g above gravity). Cross-sectional associations were analyzed by linear regression, adjusting for age, height and weight (or fat mass for models including appendicular lean mass index), comorbidities, smoking, alcohol, and Index of Multiple Deprivation.ResultsOur analyses included 380 participants, with mean age 76.7 (SD 3.0) years; 242 (64%) also completed JM. In age-adjusted analysis, a negative relationship was observed between severity of sarcopenia and high, but not medium or low, impacts (p = .03 for trend). Regarding components of sarcopenia underlying this relationship, multivariable analyses revealed that gait speed (β 1.47 [95% CI 1.14, 1.89], [β-1] reflects the proportionate increase in high impacts per SD increase in exposure) and peak force (1.40 [1.07, 1.84]) were independently associated with high impacts.ConclusionsOlder women with sarcopenia experienced fewer bone-strengthening high impacts than those with presarcopenia or without sarcopenia. To increase bone strengthening activity in older women, interventions need to improve both lower limb muscle force and walking speed.

Lean mass and lower limb muscle function in relation to hip strength, geometry and fracture risk indices in community-dwelling older women

“…We recently demonstrated the feasibility and acceptability of using jumping mechanography to assess lower limb muscle function in a sample of community-dwelling women aged over 70 years old after first excluding women with significant frailty based on their Short Physical Performance Battery (SPPB) score [ 11 ]. We subsequently used jumping mechanography estimates to identify lower limb peak muscle force as well as gait speed as two independent predictors of osteogenic impacts in this age group [ 12 ].…”

Age-Related Declines in Lower Limb Muscle Function are Similar in Power and Endurance Athletes of Both Sexes: A Longitudinal Study of Master Athletes

“…Given sex differences in use of elastic energy [ 21 ] and body composition it is also conceivable that male and female responses to power events and related training may differ. In addition, older women tend to undertake less vigorous physical activity, known to be beneficial for muscle function[ 22 ], than older men [ 23 ]. Therefore, whilst absolute training volume was similar in athletes of both sexes, this may represent a greater departure from habitual activity levels in female than male athletes.…”

Accelerating Accelerometer Research in Aging

“…Accelerometers provide an opportunity, with minimal additional participant burden, to examine physical activity beyond these simple metrics. In this issue, researchers used accelerometers to examine physical activity patterns, looking closely at "how" physical activity is accrued over the course of the day (7,8), gait and balance (9), and how the mechanical forces of activity such as vertical impacts experienced during activity (10,11).…”

“…Expanding on previous literature showing that vertical impact (the force applied in the upward or downward direction due to activity) is positively associated with bone mineral density (18,19), two studies, one by Hartley and colleagues and the other by Elhakeem and colleagues, used a hip-worn accelerometer to measure vertical impacts over 7 days among community-dwelling older women to examine the association of vertical impact intensity with sarcopenia and body composition (10,11). Both Elhakeem and colleagues and Hartley and colleagues observed that high-intensity impacts, but not lower-or moderate-intensity impacts, were associated with sarcopenia and body composition (10,11).…”

“…Both Elhakeem and colleagues and Hartley and colleagues observed that high-intensity impacts, but not lower-or moderate-intensity impacts, were associated with sarcopenia and body composition (10,11). Measuring impacts in a free-living environment during usual activities may provide a more complete picture of a participants' activity than a laboratory-based physical function test such as jumping force.…”