Strength In Older Adults Research Articles

High-intensity interval swimming improves cardiovascular endurance, while aquatic resistance training enhances muscular strength in older adults

The aim of this study was to examine the effects of free swimming (FS), aquatic resistance training (ART), and their combination (FS&ART) on the body composition, blood pressure, and physical fitness of older adults. The study employed a randomized controlled design, comparing three experimental groups with a control group. Eighty volunteers aged between sixty and seventy years (age: 66.2 ± 2.3 years; body mass index: 25.8 ± 4.3 kg/m²) participated in the 16-week intervention, consisting of two weekly sessions. Assessments were conducted at baseline and post-intervention, including anthropometric measurements, blood pressure readings, and the Senior Fitness Test. Significant differences were found between groups in post-intervention considering the chair stand test (p = 0.017; ES = 0.125), arm curl test (p = 0.029; ES = 0.111), 8-foot up and go test (p = 0.042; ES = 0.102), and walk test − 6 min (p = 0.005; ES = 0.156). Specifically, both ART (+ 20.1%; p < 0.05) and FS&ART (+ 19.5%; p < 0.05) showed significantly greater improvements in the chair stand test compared to the control group. Similarly, ART (+ 23.1%; p < 0.05) and FS&ART (+ 18.7%; p < 0.05) performed better than the control group. FS&ART also exhibited a significant improvement over the control group in the 8-foot up-and-go test (+ 14.6%; p < 0.05). In the 6-minute walk test, FS (+ 19.4%; p < 0.05) and FS&ART (+ 15.9%; p < 0.05) both significantly outperformed the control group. This study found that FS improves cardiovascular endurance, while ART enhances muscular strength and endurance in older adults, with combined benefits for agility, suggesting integration of combined modalities into community wellness initiatives for enhanced physical fitness and health outcomes.

Graded association of muscle strength with all-cause and cause-specific mortality in older adults with diabetes: Prospective cohort study across 28 countries.

The worldwide prevalence of diabetes is increasing, particularly among older adults. Understanding the association between muscle strength and mortality in this population is crucial for developing targeted exercise recommendations. To assess the prospective association of muscle strength with mortality in older adults with diabetes. From the Survey of Health, Ageing and Retirement in Europe (SHARE) study, spanning 28 countries, we included 16 149 diabetic adults aged 50 years and older (mean age 68.2 [standard deviation, SD, 9.2] years). Participants fulfilled two criteria: (1) diabetes diagnosis (ever) and (2) current use of diabetes medication. Muscle strength was assessed using handgrip dynamometry (unit: kg). Using time-varying Cox regression with restricted cubic splines, we determined the prospective association of muscle strength with all-cause and cause-specific mortality, controlling for various confounders. Over a mean follow-up of 5.9 years (SD 3.8), 2754 participants died (17%). Using the median level of muscle strength as reference (30 kg), lower and higher levels were associated in a curvilinear fashion with higher and lower all-cause mortality risk, respectively. The 10th percentile of muscle strength (17 kg) showed a hazard ratio (HR) of 1.65 (95% confidence interval (CI) 1.53-1.79). The 90th percentile (47 kg) of muscle strength showed a HR of 0.55 (95% CI 0.49-0.63). A somewhat similar pattern, with varying strength of associations, was seen for mortality due to cardiovascular disease (CVD), respiratory disease, severe infectious disease, digestive system disease and cancer. Muscle strength is gradually and inversely associated with all-cause and cause-specific mortality risk in older adults with diabetes. As muscle strength is highly adaptable to resistance training at all ages, the present findings highlight the importance of improving muscle strength in older adults with diabetes.

‘I worry about you more’: insights from older care recipients’ experiences during the Israel-Hamas war

Objectives This study explored the experiences and challenges of older adults with functional disabilities in Israel during the ongoing Israel-Hamas war, particularly those receiving care from migrant live-in carers. The main objectives were to identify their main concerns and coping strategies during this period. Method A qualitative methodology was employed, involving face-to-face interviews with 13 older adults (mean age 91.33, SD = 5.31). All participants liveded in separate housesholds with the assistance of migrant live-in carers. They were recruited through purposive and snowball sampling techniques. The interviews were analyzed using thematic content analysis. Results Two main themes emerged from data analysis: 1) Concerns for others affected by the war and concerns for oneself, and 2) Coping strategies, including utilizing personal resources such as optimism and distraction, seeking connections with family members and carers, and contributing to the community. Conclusion The study highlights the interplay between the vulnerabilities and strengths of older adults during wartime. Their ability to mobilize both internal and external coping strategies reflects an active approach to managing the stress and uncertainties of war, underscoring their resilience and agency and challenging the perception of older adults as passive recipients of care.

Association of alpha-actinin-3 genotype with muscle mass and physical function in community-dwelling older adults.

Polymorphisms (rs1815739; R577X) in the gene encoding alpha-actinin-3 (ACTN3) are thought to be associated with body composition and physical function in older people and athletes. RR homozygotes are associated with greater expression of ACTN3 protein in muscle than the X-allele carriers. We aimed to investigate the association between ACTN3 R577X polymorphism and appendicular skeletal muscle mass, walking speed, and muscle strength in older adults. A cross-sectional analysis was performed on 265 community-dwelling older adults (mean age 74.0 ± 5.8years, 63.4% female) who provided data on ACTN3 gene polymorphisms and completed surveys in the Tarumizu study conducted between 2018 and 2019. Genetic polymorphisms were categorized as RR homozygous and X allele. Muscle mass was assessed using the appendicular skeletal muscle mass index (ASMI), and physical function was assessed based on walking speed and relative muscle strength. Those in the bottom 25% for each sex were considered "low" and the association with ACTN3 genotype was examined. Considering ACTN3 polymorphism, 72 participants were RR homozygotes (27.2%) and 193 were X-allele carriers (72.8%). After adjusting for potential confounders, RR homozygosity was associated with not having low muscle mass (odds ratio 0.39, 95% confidence interval 0.19-0.82, p = 0.013) but not with low walking speed and muscle strength. The association between ACTN3 genotype and physical function in community-dwelling older adults is not clear; however, it is considered to be associated with muscle mass.

Effects of Resistance Training Volume on Physical Function, Lean Body Mass and Lower-Body Muscle Hypertrophy and Strength in Older Adults: A Systematic Review and Network Meta-analysis of 151 Randomised Trials.

The optimal prescription and precise recommendations of resistance training volume for older adults is unclear in the current literature. In addition, the interactions between resistance training volume and program duration as well as physical health status remain to be determined when assessing physical function, muscle size and hypertrophy and muscle strength adaptations in older adults. This study aimed to determine which resistance training volume is the most effective in improving physical function, lean body mass, lower-limb muscle hypertrophy and strength in older adults. Additionally, we examined whether effects were moderated by intervention duration (i.e. short term, < 20weeks; medium-to-long term, ≥ 20weeks) and physical health status (i.e. physically healthy, physically impaired, mixed physically healthy and physically impaired; PROSPERO identifier: CRD42023413209). CINAHL, Embase, LILACS, PubMed, Scielo, SPORTDiscus and Web of Science databases were searched up to April 2023. Eligible randomised trials examined the effects of supervised resistance training in older adults (i.e. ≥ 60years). Resistance training programs were categorised as low (LVRT), moderate (MVRT) and high volume (HVRT) on the basis of terciles of prescribed weekly resistance training volume (i.e. product of frequency, number of exercises and number of sets) for full- and lower-body training. The primary outcomes for this review were physical function measured by fast walking speed, timed up and go and 6-min walking tests; lean body mass and lower-body muscle hypertrophy; and lower-body muscle strength measured by knee extension and leg press one-repetition maximum (1-RM), isometric muscle strength and isokinetic torque. A random-effects network meta-analysis was undertaken to examine the effects of different resistance training volumes on the outcomes of interest. We included a total of 161 articles describing 151 trials (n = 6306). LVRT was the most effective for improving timed up and go [- 1.20 standardised mean difference (SMD), 95% confidence interval (95% CI): - 1.57 to - 0.82], 6-min walk test (1.03 SMD, 95% CI: 0.33-1.73), lean body mass (0.25 SMD, 95% CI: 0.10-0.40) and muscle hypertrophy (0.40 SMD, 95% CI: 0.25-0.54). Both MVRT and HVRT were the most effective for improving lower-limb strength, while only HVRT was effective in increasing fast walking speed (0.40 SMD, 95% CI: - 0.57 to 0.14). Regarding the moderators, our results were independent of program duration and mainly observed for healthy older adults, while evidence was limited for those who were physically impaired. A low resistance training volume can substantially improve healthy older adults' physical function and benefits lean mass and muscle size independently of program duration, while a higher volume seems to be necessary for achieving greater improvements in muscle strength. A low volume of resistance training should be recommended in future exercise guidelines, particularly for physically healthy older adults targeting healthy ageing.

Acute and chronic effects of stretching on balance – A systematic review with multilevel meta-analysis

Introduction One-third of individuals over the age of 65 fall at least once per year. Lacroix et al. (2017) shows that supervised strength training improves balance and muscle strength, which might beneficially impact the risk of falls. The American Geriatrics Society and the American Academy of Orthopaedic Surgeons recommend resistance training to improve balance (McMurdo, 2002). However, administrative burden such as limited mobility can reduce engagement among older adults for common training routines and call for the development of alternatives, but no review has investigated whether stretching has acute or chronic effects on balance. Purpose Since recent studies pointed out that high volumes of stretch could be used interchangeable with resistance training, but can be safely used without supervision (Warneke et al., 2024), this systematic review with meta-analysis investigate the effects of stretching on balance parameters across the lifespan. Methods PubMed, Web of Science, and Scopus were screened for (randomized) controlled trials (RCTs) on acute and chronic stretching effects, with subgroup analyses for a) stretching types, and b) different balance tasks, e.g., standing as still as possible on a force plate to measure the center of pressure (CoP) with eyes open (EO) and eyes closed, as well as Y-balance and star excursion test were conducted. We assessed risk of bias, while certainty of evidence was assessed in accordance with the GRADE working group guidelines. Statistical calculations were performed with R (version 4.2.3). Effect sizes (ES) were quantified using the packages Robumeta and Meta. Results Out of 18 acute studies, 15 compared acute stretching effects to passive control, while 4 performed comparisons to an active control, resulting in small magnitude effects on CoP/Sway EO (ES: 0.21, p = 0.03). Out of eleven chronic studies, seven had passive control, and 5 an active control group, resulting in moderate balance improvements with ES reaching 0.63, p = 0.04 for CoP/Sway EO. The remaining effects remained unsignificant (p = 0.091 - 1). Discussion While flexibility is commonly performed to enhance flexibility, it can also positively impact balance in some conditions. While our research question was derived via the positive association between strength and balance (Muehlbauer et al., 2015), and the possibility to use high volume stretching to enhance strength (Warneke et al., 2024), neither used included studies stretching durations of sufficient length, nor was strength measured as an outcome. It is noteworthy that most of the included studies did not interpret stretching effects in the light of underlying physiology, but on a more phenomenological basis, making a final conclusion about potential mechanisms complicated. Conclusion Although our results indicated beneficial effects of stretching on balance in some subgroup analyses, underlying mechanisms remain speculative, yet. There is a dearth of high-quality randomized controlled studies, using reasonable stretching times to enhance strength and muscle size via stretch to check whether there is the potential to use stretch-mediated hypertrophy and strength increases as a viable alternative to common resistance training and balance programs when aiming to enhance balance. References Lacroix, A., Hortobágyi, T., Beurskens, R., &amp; Granacher, U. (2017). Effects of supervised vs. unsupervised training programs on balance and muscle strength in older adults: A systematic review and meta-analysis. Sports Medicine, 47(11), 2341–2361. https://doi.org/10.1007/s40279-017-0747-6 McMurdo, M. E. T. (2002). ‘Guideline for the prevention of falls in older persons’: Essential reading. Age and Ageing, 31(1), 13–14. https://doi.org/10.1093/ageing/31.1.13 Muehlbauer, T., Gollhofer, A., &amp; Granacher, U. (2015). Associations between measures of balance and lower-extremity muscle strength/power in healthy individuals across the lifespan: A systematic review and meta-analysis. Sports Medicine, 45(12), 1671–1692. https://doi.org/10.1007/s40279-015-0390-z Warneke, K., Lohmann, L. H., Behm, D. G., Wirth, K., Keiner, M., Schiemann, S., &amp; Wilke, J. (2024). Effects of chronic static stretching on maximal strength and muscle hypertrophy: A systematic review and meta-analysis. Sports Medicine – Open, 10, Article 45. https://doi.org/10.1186/s40798-024-00706-8

The Immediate Effects of a Single 20-Minute Session of Transcranial Direct Current Stimulation (tDCS) on Muscle Strength in Older Adults

The older population often experiences a gradual age-related decline in the primary motor cortex, leading to muscle weakness that can harm their physical performances. Exercise could improve physical performance and prevent falling in older adults. However, the decrease in motor function and motor skills in older adults reduces the efficiency of fall prevention. Transcranial Direct Current Stimulation (tDCS) is a non-invasive intervention aimed at improving muscle strength in various conditions by utilizing transcranial direct current stimulation applied to the primary motor cortex (M1). Pre- and post-studies were conducted to demonstrate the effects of a single 20-minute session of tDCS alone, as well as to assess any potential side effects. Sixteen older individuals, both male and female, aged 65 years or older, with or without underlying diseases, were assessed for leg and hand grip strength, followed by physical performance tests. Subsequently, they underwent stimulation of the primary motor cortex through the placement of anodal tDCS (a-tDCS) over the left M1 for 20 min. Immediate effects were evaluated within 24 h, and side effects were recorded for up to 2 weeks after the stimulation. The results demonstrated that a single session of tDCS led to a significant increase in leg strength by 13 kg (5.9 to 20.1 kg, p &lt; 0.01). There was also a significant correlation observed with hand grip strength (r = 0.68, p &lt; 0.01). All physical performance tests, except the fastest speed in the 10-meter walk test, showed statistically significant improvements (p &lt; 0.01). Participants reported no serious side effects, and the intervention will now be incorporated into prospective clinical studies involving older populations to compare its effectiveness with other treatments. HIGHLIGHTS A single session of tDCS led to a significant increase in leg strength. A single session of tDCS, with a significant correlation observed with hand grip strength. Physical performance tests showed statistically significant improvements after a single session of tDCS. Participants reported no serious side effects. This intervention will now be incorporated into prospective clinical studies involving older populations to compare its effectiveness with other treatments. GRAPHICAL ABSTRACT

Accuracy Validation of a Sensor-Based Inertial Measurement Unit and Motion Capture System for Assessment of Lower Limb Muscle Strength in Older Adults-A Novel and Convenient Measurement Approach.

(1) Background: The aim of this study was to assess lower limb muscle strength in older adults during the transfer from sitting to standing (STS) using an inertial measurement unit (IMU). Muscle weakness in this population can severely impact function and independence in daily living and increase the risk of falls. By using an IMU, we quantified lower limb joint moments in the STS test to support health management and individualized rehabilitation program development for older adults. (2) Methods: This study involved 28 healthy older adults (13 males and 15 females) aged 60-70 years. The lower limb joint angles and moments estimated using the IMU were compared with a motion capture system (Mocap) (pair t-test, ICC, Spearman correlations, Bland-Altman plots) to verify the accuracy of the IMU in estimating lower limb muscle strength in the elderly. (3) Results: There was no significant difference in the lower limb joint angles and moments calculated by the two systems. Joint angles and moments were not significantly different (p > 0.05), and the accuracy and consistency of the IMU system was comparable to that of the Mocap system. For the hip, knee, and ankle joints, the ICCs for joint angles were 0.990, 0.989, and 0.885, and the ICCs for joint moments were 0.94, 0.92, and 0.89, respectively. In addition, the results of the two systems were highly correlated with each other: the r-values for hip, knee, and ankle joint angles were 0.99, 0.99, and 0.96, and the r-values for joint moments were 0.92, 0.96, and 0.85. In the present study, there was no significant difference (p > 0.05) between the IMU system and the Mocap system in calculating lower limb joint angles and moments. (4) Conclusions: This study confirms the accuracy of the IMU in assessing lower limb muscle strength in the elderly. It provides a portable and accurate alternative for the assessment of lower limb muscle strength in the elderly.

Does high-frequency resistance exercise offer additional benefits to older adults? learnings from a randomized controlled trial

ObjectiveResistance exercise is an effective strategy to improve muscle strength in older adults. A limited-load resistance would be flexible and suitable for community-based training. It was unclear whether high-frequency resistance exercise offer additional benefits to older adults. Here, we aimed to examine the effect of limited-load resistance exercise among different frequency on muscle parameters in older adults.MethodsThe current study was a single-blind, randomized controlled trial comparing the effectiveness of different-frequency resistance exercise in older adults. Change in skeletal muscle was estimated with a multi-frequency bioelectrical impedance analyzer. Demographics, physical examination, nutritional assessment, prealbumin and lymphocytes were also measured. Fisher’s precision probability test and baseline-adjusted generalized linear models were applied accordingly to analyze the influence of dose-different exercise on prevalence of sarcopenia, muscle parameters and body composition. A two-sided p value of < 0.05 was defined statistical significance.ResultsThe participants had a mean age of 71.96 years and close gender ratio. One hundred and twenty-seven participants (control 40; low-dose 46; high-dose 41) completed the 6-month exercise intervention. In contrast to control group, only high-dose exercise groups experienced improvements in muscle mass (0.66 kg, p < 0.001) and max grip strength (+ 2.17 kg, p < 0.001). There were significant dose-response effects of muscle mass (index), fat mass (index), max grip strength, 5-times sit to stand test, 6-minute walking test and visceral fat area (all ptrend <0.01).ConclusionsAs the proved dose-dependent effect, current findings supported high-frequency limited-load resistance exercise applied and extended among older adults in community.Trial RegistrationThis study was registered at Chinese Clinical Trial Registry Network (ChiCTR2200062007, Registered on 19 July 2022).

High-density lipoprotein cholesterol level and risk of muscle strength decline and sarcopenia in older adults

BackgroundRecent studies have demonstrated that very high high-density lipoprotein cholesterol (HDL-C) level was paradoxically linked with higher risk of cardiovascular mortality, all-cause mortality, and several age-related diseases. However, whether very high HDL-C level is associated with a higher risk of sarcopenia in older adults remains unclear. We aimed to investigate the association between HDL-C level and the risk of developing sarcopenia and low grip strength over time in older adults. MethodsParticipants were from the ongoing China Health and Retirement Longitudinal Study (CHARLS), which includes a nationally representative sample of adults aged ≥ 45 years and was performed from 2011 to 2020 with follow-ups every two to three years. The current study included 4031 participants aged ≥60 years. Muscle health related data were collected in wave 2011, 2013, and 2015. Based on HDL-C level at baseline, participants were categorized into five groups: <35 mg/dl, 35-40 mg/dl, 40-60 mg/dl, 60-70 mg/dl and >70 mg/dl. The main outcomes were incident sarcopenia and incident low grip strength over follow-up. Low grip strength and sarcopenia were defined according to the 2019 Consensus by the Asian Working Group for Sarcopenia. Cox proportional-hazard regression was performed to investigate the association between HDL-C level and the risk of developing sarcopenia and low grip strength in older adults. ResultsThe mean age of study sample was 67.3 (SD 6.1) years, and 49.6% were male. During an average 3.7-year follow-up, 409 (10.1%) participants developed sarcopenia and 771 (21.1%) developed low grip strength. Non-linear association was observed between HDL-C level and the hazard of developing sarcopenia and low grip strength. The multivariable model showed that compared to the reference group (40-60 mg/dl), older adults with very high HDL-C level (>70 mg/dl) had a significant higher risk of developing sarcopenia (HR 1.69, 95% CI 1.28 - 2.23) and low grip strength (HR 1.23 95% CI 1.00 - 1.51). Stratified analyses by sex revealed similar association. ConclusionsWe present the first longitudinal evidence that very high HDL-C level was associated with a significant higher risk of muscle strength decline and developing sarcopenia in older adults. It is essential to monitor the muscle health of older adults with very high HDL-C level in clinical practice.

The Association between Anthropometric Measurements and Body Composition with Hand Grip Strength among the Elderly Population in Indonesia.

Background/Objectives: Hand grip strength (HGS) is a crucial measure for evaluating muscle function and general physical ability, and it may be associated with several diseases. Previous studies have demonstrated inconsistent associations between anthropometric measurement and body composition with HGS. This study aims to investigate the association between anthropometric measurement and body composition with HGS in the elderly population residing in Indonesia. Methods: This is a cross-sectional study on older adults aged between 60 and 82 years who live in the community. Anthropometric parameters assessed in this study comprised the body mass index (BMI), mid-upper arm circumference (MUAC), calf circumference (CC), and waist circumference (WC). Subsequently, body composition measurements, including fat mass (FM), fat-free mass (FFM), muscle mass (MM), skeletal muscle mass (SMM), and the appendicular skeletal mass index (ASMI), were assessed using a body composition analyzer. Last, the measurement of HGS was conducted using a hand dynamometer. Results: A total of 109 participants were involved in this study. Our study demonstrates a significant association between anthropometric parameters, namely CC and HGS. Subsequently, several body composition parameters, including FFM, SMM, ASMI, and MM in the four extremities, are also significantly associated with HGS. However, in a multivariate analysis, only CC and FFM were able to significantly predict HGS. Conclusions: Improving CC and maintaining FFM may enhance muscle strength in older adults. This suggests that targeted exercise and nutrition programs could increase muscle mass and strength, thereby mitigating age-related decline and improving quality of life.

Enhancing Balance and Strength in Older Adults: The Impact of Pilates and Vibro-Swing Exercises.

BACKGROUND The Vibro-Swing system consists of 2 spiraled tubes containing 4 steel balls that move to generate a vibrational musculoskeletal and nervous system stimulus. This study included 45 older adults and aimed to compare balance, muscle strength, and proprioception with and without a 6-week program of Pilates training using the Vibro-Swing system. MATERIAL AND METHODS The present study included 45 older adults (mean age: 78.31±4.50). The experimental group (n=24) underwent a Pilates with Vibro-Swing exercise. The control group (n=21) participated in regular Pilates exercise. Both groups engaged in exercise for 40-50 minutes per session, twice a week, for 6 weeks, resulting in a total of 12 intervention sessions. Assessments were conducted before and after the intervention. The pre-post test evaluated balance (gait analysis, 10-meter walk test [10 MWT], functional reach test [FRT]), muscle strength (Five Times Sit-to-Stand Test [FTSS], grip strength), and proprioception (wrist joint position sense [WRT_30°]). RESULTS The experimental group exhibited statistically significant differences in velocity, cadence, 10MWT, FRT, FTSS, right grip, left grip, and wrist joint position sense (extension 30°) between the pre- and post-test (P>0.05). The experimental group exhibited statistically significant differences in gait velocity, cadence, 10 MWT, FTSS, right grip strength, FRT, and [WRT_30°] results compared with the control group (P>0.05). CONCLUSIONS The Pilates with Vibro-Swing exercise resulted in greater improvements in balance, muscle strength, and wrist joint proprioception.

A 3 month nutrition and exercise program improved hallux strength among senior daycare center users in Korea: a cluster randomized controlled trial.

With a growing aging population, the focus on the health and well-being of older adults, especially in preventing falls, becomes crucial. This 3 month study, initiated in July 2022, aimed to assess the impact of a nutrition and exercise program in senior daycare centers in Chuncheon, South Korea. A 3 month study, beginning in July 2022, included 204 older adults from 10 senior daycare centers in Chuncheon, South Korea. Randomly assigned to intervention or control groups, the intervention involved nutrition, daily toe exercises, or both. Control centers received interventions post-measurements. Pre- and post-intervention analyses used paired t-tests and multiple linear regression, assessing metrics like toe grip strength for significance. While 204 were initially enrolled, the analysis included 151 participants due to dropouts. Participants, with a mean age of 83.3 years (43.1% aged ≥ 85 years), exhibited mild to moderate cognitive impairment and multiple chronic illnesses. Health data indicated that 37.3% were obese, and the average BMI was 24.0 kg/m2. Both the intervention and control groups showed significant improvements in toe grip strength post-intervention. Specifically, the exercise-only and combined exercise-nutrition groups demonstrated significant differences in hallux strength compared to the control group after adjusting for age and gender. The study showed that a basic nutrition and exercise program increased toe strength in older adults with chronic diseases, including mild cognitive impairments. This intervention holds potential to prevent muscle strength decline and reduce fall risks in older individuals. As the first of its kind in Korean senior daycare centers, it emphasizes the need for future research and standardized programs for senior daycare users.

Sex-dependent association of serum vitamin D with muscle strength in older adults: NHANES 2001-2002.

Although several studies have suggested a potential positive association between serum vitamin D levels and muscle strength in older adults, it remains unclear whether this relationship is sex-dependent. To evaluate the association between serum 25 hydroxyvitamin D [25(OH)D] levels and muscle strength in older adults and to assess whether this association is dependent on sex. This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted between 2001 and 2002. A total of 1173 individuals aged 50-85 years (630 men and 543 women) were included in the analysis. The peak isokinetic force of the knee extensor was assessed using a kinetic communicator isokinetic dynamometer. Serum 25(OH)D levels were measured using the standardized liquid chromatography-tandem mass spectrometry method. Linear regression analyses were conducted to estimate coefficients and 95% confidence intervals for muscle strength across tertiles of serum vitamin D levels, adjusting for potential confounders. Tertiles of serum vitamin D were positively associated with muscle strength in older men (p-trend = 0.007), whereas no association was observed in older women (p-trend = 0.140) or in the total sample (men and women together; p-trend = 0.139). Serum vitamin D levels were positively associated with muscle strength specifically in older men, whereas no association was observed in older women. These results suggest that the relationship between vitamin D and strength may be sex-dependent.

Resistance Training with Instability Does Not Hamper Total Training Volume and Muscle Strength Gains in Older Adults: a Secondary Analysis from REI Study.

Resistance training with instability (REI) emerged as a promising training modality for older adults aiming to counteract age-related changes. We compared the effects of 12 weeks of REI and traditional resistance exercise (RE) on muscle strength in older adults with cognitive impairment. We further explored if total training volume (TTV) significantly differs among training groups. This is a secondary analysis of the REI study. Participants were randomly assigned to REI (n=22) or RE (n=23). RE protocol involved moderate-intensity, free-weight, and machines-based resistance exercises (3 sets, 10-15 repetitions). REI received a similar training protocol, in which exercises were simultaneously performed with instability/unstable devices (e.g., squat exercise under a foam pad or Bosu® ball). Maximal isometric strength and isokinetic parameters were assessed at baseline and after completion of a 12-week intervention through a hydraulic handgrip and isokinetic dynamometer, respectively. TTV (sets × repetitions × load) was computed based on external training load over the 12 weeks. No differences were observed between groups (p=.35) after the intervention. Over 12 weeks, REI and RE improved isometric handgrip strength (p<.001) and isokinetic performance (p=.04). We also did not find differences in the TTV between training groups (p=.28). We demonstrated that both REI and RE training induced similar gains in muscle strength. Combining unstable surfaces/instability devices did not hamper TTV, which may have clinical applications in the context of exercise for older adults.

The effect of long chain n-3 fatty acid supplementation on muscle strength in older adults: A systematic review and meta-analysis

Muscle strength and mass decline as we age, typically starting around 35–40 years, and can eventually lead to the development of sarcopenia(1). There are currently no effective drug treatments available for either the prevention or treatment of this condition(2) and whilst resistance exercise has efficacy(3) its effectiveness is limited due to issues with uptake and adherence(4). However, emerging research suggests that nutrition may offer a potentially effective approach to delay the age-related decline in muscle mass and function among older individuals(5), with LCn-3 PUFA emerging as a strong candidate.The main objective of the current study was to perform a systematic literature review with the purpose of exploring the impact of long-chain n-3 polyunsaturated fatty acid (LCn-3 PUFA) relative to control oil supplementation on muscle strength, with secondary outcomes of muscle mass and physical function in older individuals under conditions of habitual physical activity/exercise.The review protocol was registered with PROSPERO (CRD42021267011) and followed the guidelines outlined in the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement(6). The search for relevant studies was performed utilizing databases such as PubMed, EMBASE, CINAHL, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials (CENTRAL) up to June 2023. Randomized controlled trials (RCTs) in older adults comparing the effects of LCn-3 PUFA with a control oil supplement on muscle strength were included.Five studies(7,8,9,10,11) involving a total of 488 participants (348 females and 140 males) were identified that met the specified inclusion criteria and were included. Upon analyzing the collective data from these studies, it was observed that supplementation with LCn-3 PUFA did not have a significant impact on grip strength (standardized mean difference (SMD) 0.61, 95% confidence interval [−0.05, 1.27]; p = 0.07) in comparison to the control group. However, there was a considerable level of heterogeneity among the studies (I2 = 90%; p &lt; 0.001). As secondary outcomes were only measured in a few studies, with significant heterogeneity in methods, meta-analyses of muscle mass and functional abilities were not performed. Papers with measures of knee extensor muscle mass as an outcome (n = 3) found increases with LCn-3 PUFA supplementation, but studies measuring whole body lean/muscle mass (n = 2) and functional abilities (n = 4) reported mixed results.With a limited number of studies, our data indicate that LCn-3 PUFA supplementation has no effect on muscle strength or functional abilities in older adults but may increase muscle mass, although, with only a few studies and considerable heterogeneity, further work is needed to confirm these findings.

Relationship between Subjective Grip Strength and Physical Functioning among Community-Dwelling Older Women.

This study investigated the relationship between subjective grip strength and physical function in community-dwelling older women. Subjective grip strength was assessed using a questionnaire, and physical function and body composition were compared between groups with strong and weak subjective grip strength. Additionally, the two groups were compared in those with mild cognitive impairment (MCI) and those with normal cognitive function, respectively. The results showed significant differences in grip strength (p < 0.001), 30 s chair-stand (CS-30) test (p = 0.039), timed up-and-go (TUG) test (p = 0.027), maximal gait speed (p = 0.029), and skeletal muscle mass (p < 0.001). Older adults with normal cognitive function showed significant differences in grip strength (p < 0.001), quadriceps muscle strength (p < 0.009), one-leg standing time (p = 0.041), CS-30 (p = 0.002), TUG (p = 0.014), gait speed (p = 0.006), and skeletal muscle mass (p = 0.003). Older adults with low subjective grip strength had lower physical function and skeletal muscle mass. However, no items showed significant differences between groups among older adults with MCI. Thus, subjective grip strength is an indicator of an overall decline in physical function and a reduction in skeletal muscle mass in older adults, and cognitive function should be considered when assessing subjective grip strength in older adults.

Association between caffeine metabolites in urine and muscle strength in young and older adults: A cross-sectional study from NHANES 2011–2012

Elevated levels of reactive oxygen species may contribute to the gradual decline in muscle strength over time. Although caffeine and its metabolites have antioxidant properties that can mitigate oxidative stress, the association of caffeine and its metabolites with muscle strength remains unknown. To investigate whether caffeine metabolites in urine are associated with muscle strength in young and older adults. A cross-sectional study was conducted with 1145 individuals aged over 20 years (n=801<60 years and n=344≥60 years) from the National Health and Nutrition Examination Survey (NHANES) 2011-2012. Muscle strength was assessed using a handgrip dynamometer, and combined grip strength was determined by summing the highest value from each hand. Caffeine and its metabolites in urine were quantified using ultra-high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry (1-methyluric acid, 3-methyluric acid, 7-methyluric acid, 1,3-dimethyluric acid, 1,7-dimethyluric acid, 3,7-dimethyluric acid, 1,3,7-trimethyluric acid, 1-methylxanthine, 3-methylxanthine, 7-methylxanthine, 1,3-dimethylxanthine, 1,7-dimethylxanthine, 3,7-dimethylxanthine, 1,3,7-trimethylxanthine, 5-acetylamino-6-amino-3-methyluracil). Linear regression analyses were performed to determine the association of caffeine and its metabolites with muscle strength in young and older adults, adjusting for confounders. Positive associations between muscle strength and levels of 7-methyluric acid (β=0.029; p=0.021), 1,3-dimethyluric acid (β=0.008; p=0.004), 3,7-dimethyluric acid (β=0.645; p=0.012), 3-methylxanthine (β=0.020; p=0.002), 7-methylxanthine (β=0.020; p=0.006), 1,3-dimethylxanthine (theophylline) (β=0.030; p=0.004) and 3,7-dimethylxanthine (theobromine) (β=0.035; p=0.029) were observed in older adults. In contrast, no such associations were noted in young adults. Our study indicates a positive association between certain caffeine metabolites in urine and muscle strength in older adults, but not in younger individuals. These findings indicate that specific caffeine metabolites may contribute to an antioxidant role especially in older adults.

Impact of Otago versus Tai Chi Exercises on Lower Limb Strength in Older Adults

Impact of Otago versus Tai Chi Exercises on Lower Limb Strength in Older Adults

Effect of the Aquatic Program on Strength and Indicators of Sarcopenia in Elderly

The present study investigated the effect of implementing the Hidrotreinamento® aquatic program on strength and sarcopenia indicators in older people who have already practiced aquatic exercises. Methods: 51 Volunteers were organized into two groups. The experimental Hidrotreinamento® (HTG) followed a new periodized program with controlled load progression, and the Aquatic Exercise Community (AEC) control group maintained the community aquatic program they had previously carried out, a non-periodized program without controlled load progression. Both groups were subjected to the same battery of tests at the baseline and after 16 weeks of the aquatic program. Handgrip, Time Up and Go (TUG), Chair Stand Test (CST), Chair Sit and Reach Test (CSRT), Back Scratch Test (BST), body composition, and the questionnaires SARC-F and IPAQ. ANCOVA was used to compare differences between groups. Results: A significant correlation was found between age and Sarc-F (p &gt; 0.05), age and TUG (p &gt; 0.05), BMI and TUG (p &gt; 0.05), BMI and Handgrip (p &gt; 0.05), Fat mass and all strength variables (p &gt; 0.05) and between IPAQ sitting time and handgrip (p &gt; 0.05). Regarding physical tests, a significant group effect was found for handgrip and the BST (p &gt; 0.05). Relative results for changes within each group HTG and AEC, respectively, after the aquatic program were: handgrip (11.75%; 0.04%); TUG (117.2%; 12.06%); CST (21.6%; 2.96%); BSTR (21.7%; 2.5%); BSTL (12.2%; 13.6); CSRTR (6.6%; 2%); CSRTL (1.9%; 1.2%) Conclusion: The Hidrotreinamento® aquatic program appears to be effective in combating sarcopenia and increasing strength in older adults. Keywords: Muscle strength, older adults, sarcopenia, physical fitness, aging.