Reliability and effects of muscular pretension on isometric strength of older adults

There were two objectives to this study: (a) to determine the reliability of measuring isometric maximum torque (MT) and maximum rate of torque development (MRTD) of the knee extensor and flexor muscles and (b) to assess the effects of different muscular pretensions on MT and MRTD of older adults. Maximum strength of 35 untrained healthy older adults (aged 66.9?±?6.6 years; height 1.72?±?0.07 m; weight 75.2?±?9.6 kg) was measured. Strength measurement was performed with the Dr. Wolff ISO Check using a piezo-electric force transducer. MT intra-day coefficient of variation (CV) was between 3.30 and 12.40 % for both measurement sessions. Intraclass correlation coefficients (ICC) ranging from 0.71 to 0.99 showed good relative reliability. MT test–retest reliability (between sessions 1 and 2) of knee extension reached a CV between 7.10 and 9.30 % and high ICC values. The measurement of the knee flexion achieved an acceptable CV (9.40 %) at 40 % muscular pretension. MRTD was negatively influenced by muscular pretension (p <0.05). In conclusion, MT could be measured reliably over different trials using isometric strength measurement. The test–retest reliability was acceptable at knee extension with 10 to 40 % muscular pretension and with 40 % muscular pretension at knee flexion. A higher muscular pretension has no impact on MT but decreases MRTD in older adults.     

Force steadiness in the lower extremities as an independent predictor of functional performance in older women

The relationship between isometric force control and functional performance is unknown. Submaximal steadiness and accuracy were measured during a constant force-matching task at 50% of maximal isometric voluntary contraction (MVC) of the knee extensors in 19 older women (70-89 years). Other variables included MVC, rate of torque development, and EMG activity. Functional performance was assessed during maximal performance of walking endurance, chair rising, and stair climbing. Isometric steadiness (but not accuracy) was found to independently predict chair-rise time and stair-climbing power and explained more variance in these tasks than any other variable. Walking endurance was related to muscle strength but not steadiness. These results suggest that steadiness is an independent predictor of brief, stressful functional-performance tasks in older women with mild functional impairment. Thus, improving steadiness might help reduce functional limitations or disability in older adults.     

Comparison of heart-rate and blood-pressure increases during isokinetic eccentric versus isometric exercise in older adults

The authors compared heart-rate and blood-pressure responses to typical isometric (ISO) and isokinetic (90 degrees /s) eccentric (ECC) resistance-training protocols in older adults. Twenty healthy older adults (74 +/- 5 years old) performed randomly ordered ISO and isokinetic ECC exercise (3 sets of 10 repetitions) at a target intensity of 100 % of their peak ISO torque value. Heart rate and systolic (SBP) and diastolic (DBP) blood pressures were recorded continuously, and mean arterial pressure (MAP) and rate-pressure product (RPP) were calculated. ECC peak torque (139 +/- 33 N. m) was significantly greater than ISO peak torque (115 +/- 26 N. m; p <.001). All variables increased significantly (p <.001) during both ISO and ECC exercise. Changes in SBP, DBP, MAP, and RPP were significantly greater during ISO exercise than during ECC exercise (p <.001). Clinically, an isokinetic ECC exercise program enables older adults to work at the same torque output with less cardiovascular stress than ISO exercise.     

Effects of strength and power training on neuromuscular variables in older adults

The purpose of this study was to compare the neuromuscular adaptations produced by strength-training (ST) and power-training (PT) regimens in older individuals. Participants were balanced by quadriceps cross-sectional area (CSA) and leg-press 1-repetition maximum and randomly assigned to an ST group (n = 14; 63.6 ± 4.0 yr, 79.7 ± 17.2 kg, and 163.9 ± 9.8 cm), a PT group (n = 16; 64.9 ± 3.9 yr, 63.9 ± 11.9 kg, and 157.4 ± 7.7 cm), or a control group (n = 13; 63.0 ± 4.0 yr, 67.2 ± 10.8 kg, and 159.8 ± 6.8 cm). ST and PT were equally effective in increasing (a) maximum dynamic and isometric strength (p < .05), (b) increasing quadriceps muscle CSA (p < .05), and (c) decreasing electrical mechanical delay of the vastus lateralis muscle (p < .05). There were no significant changes in neuromuscular activation after training. The novel finding of the current study is that PT seems to be an attractive alternative to regular ST to maintain and improve muscle mass.     

Reliability of normalisation methods for EMG analysis of neck muscles

Acceptable reliability of normalisation contractions in electromyography (EMG) is paramount for testing conducted over a number of days or if normal laboratory strength testing equipment is unavailable. This study examined the reliability of maximal voluntary isometric contractions (MVIC) and sub-maximal (60%) isometric contractions for use in neck muscle EMG studies. Surface EMG was recorded bilaterally from eight sites around the neck at C4/5 level from five healthy male subjects. Subjects performed MVIC and sub-maximal normalisation contractions using an isokinetic dynamometer (ID) and a portable cable dynamometer with attached strain gauge (PCD) in addition to a MVIC against a manual resistance (MR). Subjects were tested in flexion, extension, left and right lateral bending and were retested by the same tester within a two-week period. Intra class correlation co-efficients (ICC) were calculated for each testing method and contraction direction and a mean ICC was calculated across all contraction directions. All normalisation methods produced excellent within-day reliability (mean ICC >0.80) but only the MVICs using the ID and PCD had acceptable reliability when assessed between-days. This study confirmed the validity of using MVICs elicited using the ID and PCD as reliable reference contractions for the normalisation of neck EMG.     

The motor-learning process of older adults in eccentric bicycle ergometer training

This study describes the motor-learning process of older individuals during the course of a training intervention on a motor-driven eccentric bicycle ergometer. Seventeen women and 16 men (64 ± 6 yr) took part in a 10-wk training program. Uniformity of force production and consistency of timing were used to describe their motor performance. The results suggested that participants improved the coefficient of variation of peak force during the intervention (measured at the 2nd, 4th, 6th, 8th, 10th, 12th, and the 18th training sessions). They reached a fairly constant level of motor performance around the 12th training session (5 wk). Age and sex affected improvements in the early phases of the learning process to an extent, but the differences diminished by the end of the intervention. These results suggest that the force control of continuous eccentric muscle contractions improves as a result of training in older adults.     

Physical variation in low-load work - physiological effects during exposure & recovery

Trends in industry are leaning towards jobs that are more stereotyped at lower workloads. Physical variation is a potential ergonomic intervention. However, little is known of physiological response to different kinds of variation. To investigate this issue, three kinds of isometric contraction patterns with the same mean amplitude, cycle time, and duty cycle were compared. Fatigue responses were measured by multiple biomechanical and physiological approaches. In exercise, sustained and intermittent contractions with zero force had a greater number of statistically significant differences in fatigue responses. Intermittent contractions with amplitude ? and 1? of mean force had effects intermediate but close to the sustained contraction. In recovery, sustained contractions led to decreased twitch forces 24 hours post-exercise whereas both intermittent contractions recovered within 60 minutes. This suggests that time varying forces, even without complete muscular rest, may be a useful intervention to reduce local and perceived fatigue in workers performing low-load tasks.     

Reliability of isokinetic and isometric knee-extensor force in older women

Because of the need for efficient, consistent strength measurements, the test-retest reliability of concentric, isometric, and eccentric strength; concentric work; and concentric power was determined in older women without a familiarization session. The reliability of measures derived from a single peak score were compared with those derived from an averaged score. On 2 occasions 25 older women with a mean age of 72 +/- 6 years performed 3 submaximal knee extensions and 5 maximal contractions on an isokinetic dynamometer at 90 degrees/s (CON), 0 degrees/s, and -90 degrees/s on both lower limbs. Statistical analyses for peak and averaged values (best 3 contractions of 5) exhibited good relative reliability (ICCs > .88), except for CON power. Typical error as a coefficient of variation and ratio limits of agreement for peak and averaged score values were larger than desired, with CON power scores demonstrating unacceptable error ranges. Although relative reliability of this 1-session assessment protocol was acceptable, further research is needed to determine whether additional practice trials could enhance absolute reliability.     

Functional benefit of power training for older adults

Aging leads to significant losses in muscle mass, strength, and the ability to independently perform activities of daily living (ADL). Typically, standard resistance training (RT) has been used to reduce these losses in function by maintaining or even increasing muscle strength in older adults. Increasing strength does not necessarily, however, result in an increase in the ability to perform ADL. There is now research suggesting that muscle power is more closely associated with the performance of ADL than muscle strength is, so training for muscle power might lead to more beneficial results in functional performance. This review of studies investigating the effect of training on ADL performance in older adults indicated that standard RT is effective in increasing strength in older adults, but power training that contains high-velocity contractions might be a more optimal means of training older adults when the emphasis is on increasing the performance of ADL.     

The effects of physical therapists' guidance on improvement in a strength-training program for the frail elderly

Elderly participants experiencing difficulty in chair rising and with a maximum knee-extensor torque below 87.5 N . m were randomized to different versions of a strength-training program for the knee-extensors: to a high-guidance group (HG; two group sessions supervised by a physical therapist and one unsupervised home session per week, n = 17), a medium-guidance group (MG; one supervised group session and two unsupervised home sessions per week, n = 16), or a control group (C; no exercise, n = 16). Maximal isometric knee strength increased more in HG than in C (p = .03) and with increasing guidance (p = .03). The effect was mainly the result of participants with low initial strength. Walking speed increased more for HG than for C (p = .02) and than for MG (p = .06). No statistically significant improvements were seen on other functional tests. In summary, the study shows a trend toward better results with more supervision, but more and larger studies are needed to confirm this.     

The Multisurface Obstacle Test for Older Adults (MSOT): development and reliability of a novel test for older adults

Locomotion is an essential component of independence and well-being at old age. Performance deficits in the gait of older adults most often become evident on multisurface and varying terrains. Research results substantiate that falls occur in everyday movement situations that are characterized by instability. A test track, the Multisurface Obstacle Test for Older Adults (MSOT), was developed to diagnose individual performance. The 10-m track consists of different obstacles and varying surfaces, which represent everyday movement situations in a compact way. Twenty-nine untrained, healthy older adults (11 men, 18 women) were tested on three different days at 1-week intervals in a test–retest design by the same conductor. Mean age of the participants was 68.8?±?5.3 years with a mean body mass index of 24.4?±?2.5 kg/m². The measured outcome variable was the required time (seconds) on the MSOT. The feasibility for the tested sample of untrained older adults was very good. The MSOT was undertaken safely by the participants, and no falls occurred. The range of the mean for time was between 8.12?±?1.53 s and 9.00?±?1.62 s. Regarding intertrial reliability, mean differences (MD) of ?3.39 to ?5.52 % and coefficients of variation (CV) of 2.72 to 4.19 % between the first and second trials and MD of ?0.69 to ?0.85 % and CV of 2.57 to 4.54 % over the three test sessions were observed. The correlation coefficients between the sessions were .92–.98. There were significant differences (p?<?.05) between the first and second trials of each session and between the first and second sessions. The smallest detectable differences (SDD) revealed that a small improvement is enough to detect changes in performance in the MSOT. Selecting tasks from real-life situations of older adults contributes to substantiate practical usability of the MSOT. The measured time on the MSOT showed high relative and absolute reliability in the target group of older adults between 60 and 80 years.     

An integrated dementia intervention for Korean older adults

Called dotage in Korea, dementia is primarily characterized by cognitive impairments. Secondary manifestations include mental-emotional problems, including depression. This study was designed to examine the effects of an integrated dementia intervention for Korean older adults. The intervention is composed of cognitive stimulation training, exercise, music, art, and horticultural therapy. Participants included 38 older adults with mild dementia. Twenty were assigned to the experimental group and 18 to the control group. Participants in the experimental group attended 18 program sessions. Significant differences were found postintervention between the two groups in measures of cognitive function, depression levels, and mental-emotional health. The findings indicate that this integrated dementia intervention can be applied to help older adults with mild dementia.     

Does yoga engender fitness in older adults? A critical review

Interest in yoga is growing, especially among older adults. This review critically summarizes the current literature to investigate whether physical fitness and function benefits are engendered through the practice of yoga in older adults. A comprehensive search yielded 507 studies; 10 studies with 544 participants (69.6 ± 6.3 yr, 71% female) were included. Large variability in yoga styles and measurement outcomes make it challenging to interpret results across studies. Studies reported moderate improvements for gait (ES = 0.54, 0.80), balance (ES = 0.25-1.61), upper/lower body flexibility (ES = 0.25, 0.70), lower body strength (ES = 0.51), and weight loss (ES = 0.73, 0.99).Yoga may engender improvements in some components of fitness in older adults. However, more evidence is needed to determine its effectiveness as an alternative exercise to promote fitness in older adults. Further investigation into yoga as an exercise activity for older adults is warranted.     

Designing a “Think-Along Dwelling” for People With Dementia: A Co-Creation Project Between Health Care and the Building Services Sector

Ageing-in-place is the preferred way of living for older individuals in an ageing society. It can be facilitated through architectural and technological solutions in the home environment. Dementia poses additional challenges when designing, constructing, or retrofitting housing facilities that support ageing-in-place. Older adults with dementia and their partners ask for living environments that support independence, compensate for declining and vitality, and lower the burden of family care. This study reports the design process of a demonstration home for people with dementia through performing a literature review and focus group sessions. This design incorporates modifications in terms of architecture, interior design, the indoor environment, and technological solutions. Current design guidelines are frequently based on small-scale studies, and, therefore, more systematic field research should be performed to provide further evidence for the efficacy of solutions. The dwellings of people with dementia are used to investigate the many aspects of supportive living environments for older adults with dementia and as educational and training settings for professionals from the fields of nursing, construction, and building services engineering.     

The Lichtenberg Financial Decision Screening Scale (LFDSS): A new tool for assessing financial decision making and preventing financial exploitation

ABSTRACT

One of the challenges in preventing the financial exploitation of older adults is that neither criminal justice nor noncriminal justice professionals are equipped to detect capacity deficits. Because decision-making capacity is a cornerstone assessment in cases of financial exploitation, effective instruments for measuring this capacity are essential. We introduce a new screening scale for financial decision making that can be administered to older adults. To explore the scale’s implementation and assess construct validity, we conducted a pilot study of 29 older adults seen by APS (Adult Protective Services) workers and 79 seen by other professionals. Case examples are included.     

Survivor Feedback on a Safety Decision Aid Smartphone Application for College-Age Women in Abusive Relationships

College-age women are at high risk for dating violence and tend to seek services at rates lower than older adults. Young women are more likely to look to their peers or to technology as a forum for accessing safety resources. This study explores a prototype smart phone application (“app”) that is a safety decision aid for female survivors of dating violence. The app is intended to assist young women to assess the danger in their abusive relationship, set priorities for safety, and develop a personalized safety plan. Through focus group sessions and individual interviews, 38 female college students in 4 states (Arizona, Maryland, Missouri, and Oregon) who self-identified as survivors of abusive relationships reviewed and provided feedback on the usefulness, understandability, appropriateness, and comprehensiveness of the app. The focus group sessions and interviews were transcribed and analyzed. Participants were positive about the potential of the app to provide personalized information about abusive dating relationships and appropriate resources in a private, safe, and nonjudgmental manner. Detailed feedback from survivors and recommendations for further development of the app are discussed.     

Self-regulatory strength depletion and muscle-endurance performance: a test of the limited-strength model in older adults

Self-regulation consumes a form of strength or energy. The authors investigated aftereffects of self-regulation depletion on muscle-endurance performance in older adults. Participants (N = 61, mean age = 71) were randomized to a self-regulation-depletion or control group and completed 2 muscle-endurance performance tasks involving isometric handgrip squeezing that were separated by a cognitive-depletion task. The depletion group showed greater deterioration of muscle-endurance performance than controls, F(1, 59) = 7.31, p = .009. Results are comparable to those of younger adults in a similar study and support Baumeister et al.'s limited-strength model. Self-regulation may contribute to central-nervous-system fatigue; however, biological processes may allow aging muscle to offset depletion of self-regulatory resources affecting muscle-endurance performance.     

Effects of multicomponent training on functional fitness in older adults

The purpose of this study was to evaluate the effects of a 9-week supervised multicomponent exercise program on functional fitness and body composition in independent older adults. Forty-two adults age 60-86 years were randomly assigned to an exercise or a control group and were evaluated before and after training. The training program consisted of 3 sessions of walking, strengthening, and flexibility exercises per week. The multicomponent training program resulted in significant (p < .005) improvements on the chair stand, arm curl, 6-min walk, and up-and-go tests. The findings of this study indicate that a 9-week training program increased upper and lower body strength, aerobic endurance, and agility/dynamic balance in older adults. The most affected components of functional fitness were lower body strength and aerobic endurance. There was no effect of the 9-week training on body composition.     

The effects of high- and moderate-resistance training on muscle function in the elderly

The purpose of this study was to investigate the effects of a 12-week resistance-training program on muscle strength and mass in older adults. Thirty-three inactive participants (60-74 years old) were assigned to 1 of 3 groups: high-resistance training (HT), moderate-resistance training (MT), and control. After the training period, both HT and MT significantly increased 1-RM body strength, the peak torque of knee extensors and flexors, and the midthigh cross-sectional area of the total muscle. In addition, both HT and MT significantly decreased the abdominal circumference. HT was more effective in increasing 1-RM strength, muscle mass, and peak knee-flexor torque than was MT. These data suggest that muscle strength and mass can be improved in the elderly with both high- and moderate-intensity resistance training, but high-resistance training can lead to greater strength gains and hypertrophy than can moderate-resistance training.