Handgrip strength, quadriceps muscle power, and optimal shortening velocity roles in maintaining functional abilities in older adults living in a long-term care home: a 1-year follow-up study

Feasibility and Reliability of Quadriceps Muscle Power and Optimal Movement Velocity Measurements in Different Populations of Subjects

This study aimed to assess the feasibility and reliability of quadriceps maximal short-term power (Pmax) and corresponding optimal movement velocity (υopt-velocity at which the power reaches a maximum value) measurements in different populations of subjects. Five groups of subjects, fifty participants in each group, took part in the study: students; patients of the cardiac rehabilitation program; patients after stroke; older adults; and subjects of different ages who performed repetitive measurements with two different bicycles. The correlations calculated for the pairs of scores ranged from 0.93 to 0.99 for Pmax and from 0.86 to 0.96 for υopt (all with p < 0.001). Intraclass Correlations Coefficients (ICCs) varied from 0.93 to 0.98 for Pmax and from 0.86 to 0.95 for υopt. The standard error of measurement (SEM) varied from 16.9 to 21.4 W for Pmax and from 2.91 to 5.54 rotations(rot)/min for υopt. The coefficients of variation (CVs or SEM%) for Pmax and υopt in the stroke group were 10.6% and 11.4%, respectively; all other CVs were clearly lower than 10%. The minimal detectable change (MDC) varied from 46.6 to 59.3 W for Pmax and from 8.07 to 15.4 rot/min for υopt. MDC% varied from 9.53% to 29.3% for Pmax and from 8.19% to 31.7% for υopt, and was the highest in the stroke group. Therefore, the precision of measurements of Pmax and υopt was confirmed by very good indices of absolute and relative reliability. The proposed methodology is precise, safe, not time-consuming and feasible in older subjects and those with diseases.

The level of actual functional fitness of men from different living environments in Poland and associations with health - a cross-sectional study

BACKGROUND

The study aimed to assess the differences in functional fitness between older men living in social welfare homes (SWH) and men living in society.

METHODS

The study involved 474 men aged 60-84, including 134 men living in social welfare homes and 340 men living in community. The Senior Fitness Test was used to assess functional fitness. Body weight and height were measured. Moreover, data on age, education, taking up physical activity and place of residence were collected.

RESULTS

A significantly lower level of functional fitness of SWH residents was demonstrated compared to men living in the society (p < 0.001). A significant percentage of seniors living in SWH did not reach the normal range for the Polish population. Also, the level of education, physical activity and health self-assessment differentiated the institutionalized men from those living in the community.

CONCLUSIONS

The place of residence is a factor that differentiates seniors' functional fitness levels. The reduced fitness of social welfare home residents may also result from the low level of their daily physical activity, education and health. Introducing physical activity programs for elderly residents in social welfare homes seems reasonable.

TRIAL REGISTRATION

ISRCTN platform as 18,225,729; December 2020.

Correlation between Power Elbow Flexion and Physical Performance Test: A Potential Predictor for Assessing Physical Performance in Older Adults

BACKGROUND

With the increasing number of older adults and their declining motor and cognitive function, it is crucial to find alternative methods for assessing physical functionality. The Short Physical Performance Battery (SPPB), the Time Up and Go (TUG) test, the 4 Meter Walk Test and the Barthel Index (BI) have been used to evaluate mobility and fragility and predict falls. But some of these functional test tasks could be difficult to perform for frail older adults or bedridden patients that cannot ambulate. This study aimed to evaluate the relationship between these functional tests and the power elbow flexion (PEF test).

MATERIAL AND METHODS

A correlation study was designed with 41 older adults over 65 years of age. The upper limb muscle power was measured using a linear encoder (VITRUBE VBT) with the flexion of the elbow.

RESULTS

Strong correlations were found between the PEF test and the 4mWT (rho = 0.715, p = 0.001) and TUG (rho= -0.768, p = 0.001), indicating that the greater the upper limb muscle power is, the greater physical performance will be. Moderate correlations were also found between the PEF and Barthel Index (rho = 0.495, p = 0.001) and SPPB (rho = 0.650, p < 0.001).

CONCLUSIONS

There is a strong correlation between PEF and the functional tests, proving that older adults that have greater upper limb muscle power have better physical performance. Upper limb muscle power and PEF could be an interesting tool for the assessment of physical performance in bedridden older adults.

Determination of five times-sit-to-stand test performance in patients with multiple sclerosis: validity and reliability

PURPOSE/AIM

Although Five Times-Sit-To-Stand test (FTSST) performance is known to be a valid and reliable method in people with chronic stroke, Parkinson's disease, and balance disorder, it has not been widely studied in patients with Multiple sclerosis (MS). The main aim of this study was to evaluate validity and reliability of the FTSST in patients with MS.

METHODS

The first outcome measure of the study was the FTSST, which was conducted by two different researchers. Secondary outcome measures were Biodex Stability System (BSS), 10-meter walk test, time up go test (TUG), EDSS scoring, Fatigue Severity Scale (FSS), Barthel Index, Quadriceps Muscle strength test, Functional Reach test. Intraclass correlation coefficient (ICC) was used for the validity and reliability of the FTSST, which was made by two different researchers, and Pearson Correlation Analysis was used to determine its relationship with other measurements.

RESULTS

Interrater and test-retest reliability for the FTSST were excellent (Intraclass correlation coefficients of 0.98 and 0.99, respectively). A statistically significant correlation was found between all secondary outcome measures and FTSST (p < 0.05).

CONCLUSION

FTSST is considered to be a valid, reliable, easy, and rapid method for evaluating lower extremity muscle strength and balance in patients with MS.

Chair stand test as a proxy for physical performance and muscle strength in sarcopenia diagnosis: the Korean frailty and aging cohort study

BACKGROUND

The 5-times chair stand test (5CST) is a proxy tool for measuring physical performance and muscle strength in diagnosing sarcopenia. The Asian Working Group for Sarcopenia 2019 guidelines recommends the 5CST for evaluating gait speed, whereas the European Working Group on Sarcopenia in Older People guidelines recommend the chair stand test as a proxy for muscle strength.

AIMS

This study sought to determine whether the chair stand test correlates with handgrip strength and gait speed, and investigate sex differences in these relationships.

METHODS

We used data collected from 1416 participants (678 men and 738 women) in the 2017 Korean Frailty and Aging Cohort Study (KFACS).

RESULTS

The 5CST time had a higher correlation with gait speed (r =  - 0.470) than handgrip strength (r =  - 0.309). In addition, 5CST time predicted low gait speed (area under the curve [AUC] 0.727) better than low handgrip strength (AUC 0.641). The optimal cutoff values of the 5CST to estimate low gait speed were 10 s for men (sensitivity 62%, specificity 64%) and 11 s for women (sensitivity 68%, specificity 67%). The optimal cutoff values of the 5CST for low handgrip strength were the same as those for low gait speed (10 s for men and 11 s for women).

CONCLUSIONS

The 5-times chair stand test fits with gait speed and handgrip strength but seems to be a better proxy of gait speed than handgrip strength. The optimal cutoff values of the 5CST to estimate low gait speed and low handgrip strength were lower in men than women. Although none of the AWGS 2019 or EWGSOP guidelines present sex-specific cutoffs for the 5CST, it needs to be considered in the next guidelines.

Simpler modified fried frailty scale as a practical tool to evaluate physical frailty: Methodological report for its cross-cultural adaptation and validation

Frailty is a common geriatric syndrome that indicates homeostenosis and increased risk of disability and mortality. It is amenable to intervention when detected. Hence, screening frailty is of utmost importance to preserve quality-of-life and function in older age. Simpler Modified Fried Frailty Scale is a very practical frailty screening tool that has recently been introduced and has rooted from the original Fried Scale. It is developed in Turkish and has been shown to predict mortality in nursing home residents. Considering the variety of languages in Europe, it seems valid to adapt and validate this tool in different European languages. Thereby, it is expected that clinicians will have the possibility to screen for frailty more quickly and easily in their practice across many countries. This report is written to explain the details of the final consensus methodology suggested for Simpler Modified Fried Frailty Scale validation in order to guide and help the research teams in their studies.

Physical and Motor Fitness Tests for Older Adults Living in Nursing Homes: A Systematic Review

This systematic review aimed to identify the physical/motor fitness tests for nursing home residents and to examine their psychometric properties. Electronic databases were searched for articles published between January 2005 and October 2021 using MeSh terms and relevant keywords. Of the total of 4196 studies identified, 3914 were excluded based on title, abstracts, or because they were duplicates. The remaining 282 studies were full-text analyzed, and 41 were excluded, resulting in 241 studies included in the review. The most common physical component assessed was muscle strength; 174 (72.2%) studies assessed this component. Balance (138 studies, 57.3%) and agility (102 studies, 42.3%) were the second and third components, respectively, most widely assessed. In this review, we also describe the most used assessment tests for each physical/motor component. Some potentially relevant components such as manual dexterity and proprioception have been little considered. There are few studies assessing the psychometric properties of the tests for nursing home residents, although the data show that, in general, they are reliable. This review provides valuable information to researchers and health-care professionals regarding the physical/motor tests used in nursing home residences, helping them select the screening tools that could most closely fit their study objectives.

The Nutritional Status of Long-Term Institutionalized Older Adults Is Associated with Functional Status, Physical Performance and Activity, and Frailty

Among older adults living in long-term nursing homes (LTNHs), maintaining an adequate functional status and independence is a challenge. Whilst a poor nutritional status is a potential risk factor for a decreased function in this population, its role is not fully understood. Here, using a transversal multicenter study of 105 older adults living in 13 LTNHs, we analyzed the associations between nutritional status, as measured by the Mini Nutritional Assessment (MNA), and the parameters of functional status, physical performance, physical activity, and frailty as well as comorbidity and body composition. The MNA scores were positively correlated with the Barthel Index, handgrip strength, Short Physical Performance Battery (SPPB) scores, absolute muscle power, and Assessment of Physical Activity in Frail Older People (APAFOP) scores and were negatively correlated with dynamic balance and frailty. In a multiple linear regression model controlling for gender and age, the APAFOP score (β = 0.386), BMI (β = 0.301), and Barthel Index (β = 0.220) explained 31% of the variance in the MNA score. Given the observed close relationship between the MNA score and functional status, physical performance and activity, and frailty, interventions should jointly target improvements in both the nutritional status and functional status of LTNH residents. Strategies designed and implemented by interdisciplinary professional teams may be the most successful in improving these parameters to lead to better health and quality of life.

Relative sit-to-stand power cut-off points and their association with negatives outcomes in older adults

The purposes of this study were: (i) to evaluate the association of sit-to-stand (STS) power and body composition parameters [body mass index (BMI) and legs skeletal muscle index (SMI)] with age; (ii) to provide cut-off points for low relative STS power (STS_rel), (iii) to provide normative data for well-functioning older adults and (iv) to assess the association of low STS_rel with negative outcomes. Cross-sectional design (1369 older adults). STS power parameters assessed by validated equations, BMI and Legs SMI assessed by dual-energy X-ray absorptiometry were recorded. Sex- and age-adjusted segmented and logistic regression analyses and receiver operator characteristic curves were used. Among men, STS_rel showed a negative association with age up to the age of 85 years (− 1.2 to − 1.4%^year−1; p < 0.05). In women, a negative association with age was observed throughout the old adult life (− 1.2 to − 2.0%^year−1; p < 0.001). Cut-off values for low STS_rel were 2.5 W kg⁻¹ in men and 1.9 W kg⁻¹ in women. Low STS_rel was associated with frailty (OR [95% CI] = 5.6 [3.1, 10.1]) and low habitual gait speed (HGS) (OR [95% CI] = 2.7 [1.8, 3.9]) in men while low STS_rel was associated with frailty (OR [95% CI] = 6.9 [4.5, 10.5]) low HGS (OR [95% CI] = 2.9 [2.0, 4.1]), disability in activities of daily living (OR [95% CI] = 2.1 [1.4, 3.2]), and low quality of life (OR [95%CI] = 1.7 [1.2, 2.4]) in women. STS_rel declined with increasing age in both men and women. Due to the adverse outcomes related to STS_rel, the reported cut-off points can be used as a clinical tool to identify low STS_rel among older adults.

Quadriceps muscle power and optimal shortening velocity are inversely related to angiotensin converting enzyme activity in older men

Background: Methods which potentially could prevent age-related loss of muscle mass and function are still being sought. There are various attempts to use pharmacological agents to prevent loss of muscle mass, but the effectiveness of many of them still needs to be confirmed. One of the promising therapeutics are Angiotensin Converting Enzyme Inhibitors (ACEIs) and lowering of serum ACE activity. The goal of this study was to assess if taking Angiotensin Converting Enzyme Inhibitors (ACEI) and other angiotensin system blocking medications (ASBMs) can modify muscle performance in older men as well as to assess the association of serum ACE activity with muscle strength, power, muscle contraction velocity and functional performance. Methods: Seventy-nine older men took part in the study. Muscle function was assessed with hand grip strength, maximum power relative to body mass (Pmax) and optimal shortening velocity (Ʋopt) of the knee extensor muscles. Anthropometric data, ACE activity and functional performance were also measured. Results: Negative correlations between ACE activity and Pmax (rho=-0.29, p=0.04) as well as Ʋopt  (rho=-0.31, p=0.03) in a group of patients not taking ACEI and between ACE activity and Ʋopt (rho=-0.22, p=0.05) in the whole group of men were found. Positive relationship between age and ACE activity was demonstrated (rho=0.26, p=0.02). Age was the only selected variable in the multiple regression analyses to determine both Pmax and Ʋopt. Conclusions: Serum ACE activity negatively associates to muscle power and muscle contraction velocity. The issues related to the impact of taking ACEI on the maintenance of muscle function and functional performance in older man require further studies.

Quadriceps muscle power and optimal shortening velocity are inversely related to angiotensin converting enzyme activity in older men

Background: Methods which potentially could prevent age-related loss of muscle mass and function are still being sought. There are various attempts to use pharmacological agents to prevent loss of muscle mass, but the effectiveness of many of them still needs to be confirmed. One of the promising therapeutics are Angiotensin Converting Enzyme Inhibitors (ACEIs) and lowering of serum ACE activity. The goal of this study was to assess if taking Angiotensin Converting Enzyme Inhibitors (ACEI) and other angiotensin system blocking medications (ASBMs) can modify muscle performance in older men as well as to assess the association of serum ACE activity with muscle strength, power, muscle contraction velocity and functional performance. Methods: Seventy-nine older men took part in the study. Muscle function was assessed with hand grip strength, maximum power relative to body mass (Pmax) and optimal shortening velocity (Ʋopt) of the knee extensor muscles. Anthropometric data, ACE activity and functional performance were also measured. Results: Negative correlations between ACE activity and Pmax (rho=-0.29, p=0.04) as well as Ʋopt  (rho=-0.31, p=0.03) in a group of patients not taking ACEI and between ACE activity and Ʋopt (rho=-0.22, p=0.05) in the whole group of men were found. Positive relationship between age and ACE activity was demonstrated (rho=0.26, p=0.02). Age was the only selected variable in the multiple regression analyses to determine both Pmax and Ʋopt. Conclusions: Taking ACEI is not associated with a functional performance in older men of the same age and with the same anthropometric parameters. Serum ACE activity negatively associates to muscle power and muscle contraction velocity.

Timed Up and Go in men and women with Multiple Sclerosis: Effect of muscular strength

OBJECTIVE

People with Multiple Sclerosis (pwMS) often exhibit generalized weakness that affects several activities of daily life, particularly those relying on balance and gait. While it is known that such a symptom has a strong impact on mobility, to what extent muscular strength is linked with functional mobility in men and women with MS remains mostly unexplored. The aim of this study is to assess the existence of possible sex-related differences in functional mobility in pwMS, also considering the muscular strength capacity.

METHODS

Functional mobility and hand-grip strength (HGS) were assessed in 49 pwMS with mild-moderate disability using instrumental Timed-up-and-go (TUG) test carried out using an inertial sensor and digital dynamometry. We investigated the existence of sex-related differences in the duration of each TUG sub-phase and their correlation with the HGS.

RESULTS

No sex-related differences in TUG performance (either in terms of overall or sub-phase time) were found. Similar large negative correlations were found in men and women with MS between HGS and overall TUG and walking phase duration. However, changes in strength have a more marked impact in women as indicated by the different slope of the HGS-TUG time relationship., In women, HGS also appears significantly correlated with all TUG sub-phases, while in men this occurs only for overall TUG and walking time.

CONCLUSIONS

Rehabilitation and training programs for pwMS should take into account the peculiar features associated with the interaction between strength and mobility specific for each individual's sex to optimize their effectiveness.

Muscle mass, strength, and physical performance predicting activities of daily living: a meta-analysis

Background Activities of daily living (ADLs) and instrumental activities of daily living (IADLs) are essential for independent living and are predictors of morbidity and mortality in older populations. Older adults who are dependent in ADLs and IADLs are also more likely to have poor muscle measures defined as low muscle mass, muscle strength, and physical performance, which further limit their ability to perform activities. The aim of this systematic review and meta-analysis was to determine if muscle measures are predictive of ADL and IADL in older populations. Methods A systematic search was conducted using four databases (MEDLINE, EMBASE, Cochrane, and CINAHL) from date of inception to 7 June 2018. Longitudinal cohorts were included that reported baseline muscle measures defined by muscle mass, muscle strength, and physical performance in conjunction with prospective ADL or IADL in participants aged 65 years and older at follow-up. Meta-analyses were conducted using a random effect model. Results Of the 7760 articles screened, 83 articles were included for the systematic review and involved a total of 108 428 (54.8% female) participants with a follow-up duration ranging from 11 days to 25 years. Low muscle mass was positively associated with ADL dependency in 5/9 articles and 5/5 for IADL dependency. Low muscle strength was associated with ADL dependency in 22/34 articles and IADL dependency in 8/9 articles. Low physical performance was associated with ADL dependency in 37/49 articles and with IADL dependency in 9/11 articles. Forty-five articles were pooled into the meta-analyses, 36 reported ADL, 11 reported IADL, and 2 reported ADL and IADL as a composite outcome. Low muscle mass was associated with worsening ADL (pooled odds ratio (95% confidence interval) 3.19 (1.29-7.92)) and worsening IADL (1.28 (1.02-1.61)). Low handgrip strength was associated with both worsening ADL and IADL (1.51 (1.34-1.70); 1.59 (1.04-2.31) respectively). Low scores on the short physical performance battery and gait speed were associated with worsening ADL (3.49 (2.47-4.92); 2.33 (1.58-3.44) respectively) and IADL (3.09 (1.06-8.98); 1.93 (1.69-2.21) respectively). Low one leg balance (2.74 (1.31-5.72)), timed up and go (3.41 (1.86-6.28)), and chair stand test time (1.90 (1.63-2.21)) were associated with worsening ADL. Conclusions Muscle measures at baseline are predictors of future ADL and IADL dependence in the older adult population.

VALIDITY OF HAND-HELD DYNAMOMETRY IN MEASURING QUADRICEPS STRENGTH AND RATE OF TORQUE DEVELOPMENT

BACKGROUND

A hand-held dynamometer (HHD) offers a reliable and valid method to quantify quadriceps strength in a clinical environment. While measures of peak strength provide functional insights, most daily activities are performed quickly and do not require maximum strength. Rate of torque development (RTD) measures better reflect both the demands of daily activity and athletic movements. The capacity to obtain RTD measures in clinical settings is possible with an HHD, but the validity of RTD measures has not been quantified.

HYPOTHESIS/PURPOSE

To determine the validity of an HHD to measure quadriceps isometric strength metrics compared to isometric strength measures obtained on an isokinetic dynamometer. It was hypothesized that the HHD would be a valid measure of peak torque and RTD at all time intervals when compared to the isokinetic dynamometer.

STUDY DESIGN

Descriptive laboratory study.

METHODS

Twenty healthy participants (12 male, 8 female) (age = 23.7 ± 2.9 years, height = 174.6 ± 10.1 cm, mass = 76.4 ± 15.9 kg, and Tegner = 6.7 ± 1.2) performed maximum isometric quadriceps contractions on an isokinetic dynamometer and with an HHD. Outcome measures included quadriceps peak torque and RTD at three intervals (0-100, 0-250 ms, and average). Pearson product-moment correlation coefficients and Spearman's rank correlation coefficient were used to determine relationships between devices. Bland-Altman Plots with Limits of Agreement (LOA) calculations were used to quantify systematic bias between measurement techniques.

RESULTS

There was a significant correlation between the isokinetic dynamometer and the HHD for peak torque (p<.001, r = .894) and all RTD measurements (p<.002, r = .807; ρ = .502-.604). Bland-Altman plot LOA indicated the HHD overestimated peak torque values (19.4 ± 53.2 Nm) and underestimated all RTD measurements (-55.2 ± 190.7 Nm/s to -265.2 ± 402.6 Nm/s).

CONCLUSION

These results show it is possible to obtain valid measures of quadriceps peak torque and late RTD using an HHD. Measures of early RTD and RTDAvg obtained with an HHD were more variable and should be viewed with caution.

LEVEL OF EVIDENCE

Diagnostic, Level 3.

Changes in Central Motor Conduction Time and Its Implication on Dysfunction of Distal Upper Limb in Distal-Type Cervical Spondylotic Amyotrophy

PURPOSE

Distal-type cervical spondylotic amyotrophy (CSA) is an uncommon syndrome associated with cervical spondylosis. The pathogenic mechanism of distal-type CSA is still unclear. The aim of the current study was to analyze central motor conduction time (CMCT) in the cases with distal-type CSA and to investigate the role of cervical cord compressive injury in the distal-type CSA.

METHODS

Both 28 cases with distal-type CSA and 21 healthy subjects accepted CMCT measures, motor unit number estimation, handgrip strength examination, and magnetic resonance imaging evaluation.

RESULTS

In this study, nine (9/28, 32.1%) cases with CSA presented with prolonged CMCT, and both reduced number of motor units and decreased handgrip strength were found in these 9 cases (P < 0.05). Magnetic resonance imaging evaluation showed that 7 of these 9 patients presented with proximal cervical cord compression with or even without distal selective compression consistent with segmental atrophy. A negative relationship between CMCT and both number of motor units and handgrip strength was found on the symptomatic side (P < 0.05), and there was a positive correlation between CMCT and amplitude of single motor unit potentials on the less symptomatic side (P < 0.05).

CONCLUSIONS

Corticospinal tract damage caused by proximal spinal cord compression may induce distal motor unit loss to worsen in some cases with distal-type CSA, which may contribute to the dysfunction of the distal upper limb in some cases with distal-type CSA. Therefore, treatment and rehabilitation efforts should account for both distal selective compression and proximal cord compression in distal-type CSA.

Smaller erector spinae muscle size is associated with inability to recover activities of daily living after pneumonia treatment

BACKGROUND

Elderly patients who are hospitalized due to pneumonia experience deterioration of their activities of daily living (ADL) during this period; in some cases, this loss of ADL is not recovered at the end of antibiotic treatment. In this study, we examined whether erector spinae muscle cross-sectional area (ESMCSA) measured by computed tomography (CT) could predict a low level of ADL at the end of antibiotic treatment for pneumonia.

METHODS

Eighty patients (mean age 74.8 years) with pneumonia, who were admitted to Yamagata university hospital between 2015 and 2016, were analyzed retrospectively. In all cases, chest CT was performed on admission and ESMCSA was measured at the level of the 12th thoracic vertebra. Patient levels of ADL were also measured, both on admission and at the end of treatment, using the Barthel Index.

RESULTS

Patients with lower levels of ADL at the end of treatment were significantly older and tended to have a lower body mass index, poorer nutritional status, and more severe pneumonia than did patients who were self-reliant. Significantly smaller ESMCSAs were noted in patients who required assistance at the end of treatment than in those who were self-reliant. In multivariate logistic regression analysis, smaller ESMCSA was significantly associated with a lower level of ADL at the end of treatment, independent of age, sex, severity of pneumonia, nutritional status, or dehydration status.

CONCLUSION

These results suggest that ESMCSA can predict ADL level after antibiotic treatment of pneumonia.

CAN anterior cervical fusion procedures prevent the progression of the natural course of Hirayama disease? An ambispective cohort analysis

OBJECTIVE

To clarify the effectiveness of anterior cervical fusion (ACF) in the treatment of Hirayama disease (HD).

METHODS

Sixty-nine HD patients who accepted ACF procedures underwent dynamic F-waves before and soon after operation, and 36 of the 69 patients underwent pre- and postoperative magnetic resonance imaging (MRI). Motor unit number estimation, handgrip strength (HGS) and disabilities of arm, shoulder and hand (DASH) were performed in these 36 HD patients and in the other 24 patients who accepted neither neck-collar support nor operation, and these tests were reassessed about one year after initial test.

RESULTS

Postoperatively, dynamic F-wave abnormalities were observed in fewer HD cases (2/69 vs. 25/69), and neck-flexion MRI abnormalities decreased significantly (P < 0.05). Compared with motor unit loss in patients who were untreated, follow-up analysis demonstrated no differences in motor unit, HGS or DASH in HD patients who underwent operation (P > 0.05), and mild recovery of motor units was observed in patients with preoperative abnormal dynamic F-waves (P < 0.05).

CONCLUSIONS

ACF procedures can immediately remove neck-flexion abnormalities and prevent or delay the progression of HD.

SIGNIFICANCE

ACF procedures may provide effective, reliable and alternative methods for the treatment of HD, especially in HD patients with functional evidence of neck-flexion abnormalities.

Relationship of quadriceps muscle power and optimal shortening velocity with angiotensin-converting enzyme activity in older women

BACKGROUND

The goal of this study was to assess whether angiotensin-converting enzyme (ACE) activity is related to muscle function (strength, power and velocity), as well as to assess if ACE inhibitors (ACEIs) and other angiotensin system blocking medications (ASBMs) influence muscle performance in elderly women.

SUBJECTS AND METHODS

Ninety-five community-dwelling elderly women took part in this study. Anthropometric data, blood ACE activity analysis, maximum power (Pmax) and optimal shortening velocity (υopt) of the knee extensor muscles, handgrip strength, physical activity (PA) and functional performance were measured.

RESULTS

Women taking ACEI were on average almost 2 years older than the women who did not take ACEI. They took more medicines and were also characterized by significantly lower level of ACE, but they did not differ in terms of PA level, results of functional performance and parameters characterizing muscle functions. No correlations of ACE activity with Pmax and handgrip strength, as well as with PA or functional performance were found. Higher ACE activity was connected with lower υopt for women who did not take any ASBMs (rho =-0.37; p=0.01).

CONCLUSION

Serum ACE activity was not associated with muscle strength, power and functional performance in both ASBM users and nonusers, but was associated with optimal shortening velocity of quadriceps muscles in older women. Further prospective studies are needed to assess if ACEIs or other ASBMs may slow down the decline in muscle function and performance.