-Robert, Temprado, & Berton, 2011 ). For a static force task with visual feedback, older adults exhibit greater force fluctuations with less complexity than do young adults ( Challis, 2006 ; Kennedy & Christou, 2011 ) due to ineffective use of visual information for force gradation ( Chen, Lin, Lin, Hu, & Hwang
Yi-Ching Chen, I-Chen Lin, Yen-Ting Lin, Wei-Min Huang, Chien-Chun Huang and Ing-Shiou Hwang
Pai-Yun Cheng, Hsiao-Feng Chieh, Chien-Ju Lin, Hsiu-Yun Hsu, Jia-Jin J. Chen, Li-Chieh Kuo and Fong-Chin Su
-extremity functions ( Liu et al., 2017 ; Shiffman, 1992 ). Muscle strength will be restrained by the number and mechanical properties of motor units ( Carmeli, Patish, & Coleman, 2003 ), and reduced sensory inputs might affect the sensorimotor coordination and force control of older adults ( Cole, 1991 ). Decreasing
Kelsey Lucca, David Gire, Rachel Horton and Jessica A. Sommerville
key elements of cognition, affect, and motor behavior. To illustrate, imagine locking your keys inside a car. To get them out, you might draw on motor abilities and exert high levels of force in trying to pry the door open. You might recruit cognitive resources and contemplate the most strategic way
Hilde Lohne-Seiler, Monica K. Torstveit and Sigmund A. Anderssen
The aim was to determine whether strength training with machines vs. functional strength training at 80% of one-repetition maximum improves muscle strength and power among the elderly. Sixty-three subjects (69.9 ± 4.1 yr) were randomized to a high-power strength group (HPSG), a functional strength group (FSG), or a nonrandomized control group (CG). Data were collected using a force platform and linear encoder. The training dose was 2 times/wk, 3 sets × 8 reps, for 11 wk. There were no differences in effect between HPSG and FSG concerning sit-to-stand power, box-lift power, and bench-press maximum force. Leg-press maximum force improved in HPSG (19.8%) and FSG (19.7%) compared with CG (4.3%; p = .026). Bench-press power improved in HPSG (25.1%) compared with FSG (0.5%, p = .02) and CG (2%, p = .04). Except for bench-press power there were no differences in the effect of the training interventions on functional power and maximal body strength.
James R. Chagdes, Joshua J. Liddy, Amanda J. Arnold, Laura J. Claxton and Jeffrey M. Haddad
Background Posture and Balance Assessments in Developmental Research The maturation of posture and balance is often examined by collecting center of pressure (CoP) data from research-grade force plates. The CoP time series is then used to calculate a variety of time-dependent and time
Caroline W. Stegink Jansen, Bruce R. Niebuhr, Daniel J. Coussirat, Dana Hawthorne, Laura Moreno and Melissa Phillip
This cross-sectional study aimed to assess the impact of age and gender on 4 measures of grip and pinch force of well elderly community dwellers and to provide normative values. The hypotheses were that age and gender affect pinch and grip force and that these 2 factors might interact. Hand strength of 224 seniors 65–92 years old was tested. Grip and pinch force decreased in successively older age groups past 65 years. Men’s grip force exceeded that of women in all age groups. Men’s hand-force decline was steeper than that of women over successive age groups, suggesting that gender differences in force decreased with age. Trends were the same for all 4 types of grip- and pinch-force measurement but were most clearly visible in grip and key-pinch force. Norms were provided for seniors age 65–85+ years in 5-yr increments.
Kathleen Williams, Kathleen Haywood and Ann VanSant
Older adults were tested to clarify findings of an earlier examination of movement responses to shifting task requirements (Williams et al., 1993). Eleven participants (average age = 77 years) were evaluated on form and velocity as they performed overarm throws for force and accuracy. Significant gender and force-accuracy differences occurred for resultant velocity. Although no statistically significant differences occurred for force-accuracy comparisons of movement form, there were trends toward change in most movement components. Additionally, many individuals displayed change in one or more components as they shifted from force to accuracy throws. Results of this study point to the importance of examining developmental status and task requirements simultaneously.
Kathleen Williams, Kathleen Haywood and Ann VanSant
Older adults threw tennis balls for force and accuracy to examine their adaptability to different task demands. Twenty-one (13 women, 8 men) participants were videotaped as they performed five force and five accuracy throws. The developmental level of each throw was determined; resultant ball velocities also were examined. Roberton’s (1977, 1978) movement components were used in the former analysis. The typical pattern of gender differences occurred for both movement component and velocity measures. Men performed at higher levels than women. Only minor force versus accuracy differences were found in the movement patterns used by either men or women; none of these differences were significant. Clear task differences occurred for ball velocities. Men’s forceful throws were faster than those for accuracy; women’s throws did not differ for the two tasks. The generally lower developmental level of women’s throws accounted for gender differences in velocity. Insufficient task differences may explain the lack of clear contrast in movement patterns.
AmirAli Jafarnezhadgero, Morteza Madadi-Shad, Christopher McCrum and Kiros Karamanidis
Human lower limbs contribute to locomotion in multiple ways; acting as springs, as force absorbing dampers, or as actuators ( Brown, O’Donovan, Hasselquist, Corner, & Schiffman, 2016 ; Raynor, Yi, Abernethy, & Jong, 2002 ). The progression of ground reaction forces (GRF) through the lower limbs
Gregory W. Heath, Ross C. Brownson, Judy Kruger, Rebecca Miles, Kenneth E. Powell, Leigh T. Ramsey and the Task Force on Community Preventive Services
Although a number of environmental and policy interventions to promote physical activity are being widely used, there is sparse systematic information on the most effective approaches to guide population-wide interventions.
We reviewed studies that addressed the following environmental and policy strategies to promote physical activity: community-scale urban design and land use policies and practices to increase physical activity; street-scale urban design and land use policies to increase physical activity; and transportation and travel policies and practices. These systematic reviews were based on the methods of the independent Task Force on Community Preventive Services. Exposure variables were classified according to the types of infrastructures/policies present in each study. Measures of physical activity behavior were used to assess effectiveness.
Two interventions were effective in promoting physical activity (community-scale and street-scale urban design and land use policies and practices). Additional information about applicability, other effects, and barriers to implementation are provided for these interventions. Evidence is insufficient to assess transportation policy and practices to promote physical activity.
Because community- and street-scale urban design and land-use policies and practices met the Community Guide criteria for being effective physical activity interventions, implementing these policies and practices at the community-level should be a priority of public health practitioners and community decision makers.