Comparison of maximal muscle strength of elbow flexors and knee extensors between younger and older men with the same level of daily activity

Comparing position sense and isokinetic strength of the muscles of elbow joint between aikidokas and non-athlete people

BACKGROUND

Aikido is a martial art comprises of locking techniques and falls. During the locking techniques, the elbow joint is forced into extended position. Moreover, the elbow hits the ground during the falling techniques. These might compromise joint position sense (JPS). The objectives of this study were to compare JPS and strength of the muscles of elbow joint between Aikidokas and a non-athlete group and to evaluate the correlation between JPS and muscle strength among Aikidokas.

METHODS

All male Jiyushinkai style Aikidokas and a healthy matched non-athlete group participated in this cross-sectional study. Passive JPS at a speed of 4°/s and the isokinetic strength of elbow flexors and extensors were assessed.

RESULTS

Evaluating the isokinetic parameters revealed no significantly difference between the groups in either flexion or extension at speeds of 60 (P-value range: 0.2-0.99) and 120 °/s (P-value range: 0.05-0.96). Also, the groups had no significant difference regarding different types of reconstruction error including constant error (P-value range: 0.38-0.91), variable error (P-value range: 0.09-0.87), and total variability (P-value range: 0.30-0.80). Moreover, very weak to weak correlation was observed between isokinetic parameters and passive JPS (r-value range: 0.01-0.39).

CONCLUSIONS

JPS was not impaired in Aikidokas in spite of the repetitive stress applied to the elbow joint during the performance of Aikido techniques. The lack of significant difference in isokinetic between Aikidokas and healthy non-athletes, and the absence of an acceptable correlation between IPS and muscle strength in Aikidokas, might be attributed to the soft nature of Aikido.

Can phase angle from bioelectrical impedance analysis associate with neuromuscular properties of the knee extensors?

Maintenance and improvement of neuromuscular functions is crucial for everyone regardless of age. An easy way to assess neuromuscular properties without muscle contraction is useful especially for those who cannot perform strenuous muscular force production, such as older adults and patients with orthopedic or cognitive disorders. Bioelectrical impedance analysis (BIA) can assess body electrical properties e.g., phase angle (PhA) which is regarded as muscle quantity/quality index. The purpose of this study was to investigate associations of PhA with neuromuscular properties of the knee extensors in 55 young (n = 23) and older (n = 32) adults. The values of PhA of the right thigh and whole-body were determined with BIA at 50 kHz. The participants performed 4-s maximal voluntary isometric contraction (MVIC) to measure peak torque (PT_MVIC), and 1-s brief MVIC to assess rate of torque development (RTD) over the time interval of 0–200 ms. As markers of physiological mechanisms of muscle force production, twitch contractile properties (peak twitch torque, rate of twitch torque development, and time-to-peak twitch torque) of the knee extensors obtained by femoral nerve electrical stimulation, and muscle activity assessed as root mean square values of electromyographic activity (EMG-RMS) during PT_MVIC and RTD measurements were measured. Thigh and whole-body PhA significantly correlated with PT_MVIC (r ≥ 0.555, p < 0.001) and electrically evoked twitch parameters (peak twitch torque, rate of twitch torque development, and time-to-peak twitch torque; |r| ≥ 0.420, p ≤ 0.001), but not RTD (r ≤ 0.237, p ≥ 0.081) or EMG-RMSs (|r| ≤ 0.214, p ≥ 0.117). Stepwise multiple linear regression analysis revealed that thigh PhA was selected as a significant variable to predict PT_MVIC but not RTD. Whole-body PhA was not selected as a significant variable to predict PT_MVIC or RTD. In conclusion, both thigh and whole-body PhA can associate with maximal voluntary muscle strength of the knee extensors, and this association may be due to intrinsic contractile properties but not neural aspects. Regarding prediction of the knee extensor strength, thigh PhA is preferable as the predictor rather than whole-body PhA which is used as a widely acknowledged indicator of sarcopenia.

Exploring the association between handgrip, lower limb muscle strength, and physical function in older adults: A narrative review

Widely used in daily practice, handgrip strength (HGS) is a low cost, easy-to-use, and portable test to assess overall muscle and physical function. It can be used as a stand-alone or a first-line tool for evaluating muscle weakness, though controversy surrounds its use for assessing global or lower limb muscle function. Lower limb mobility and physical activity are reduced with advancing age. This decline is difficult to quantify with isokinetic or isometric devices in routine settings (hospital and nursing home). For this narrative review we explored and summarized the findings of studies that investigated the association between HGS, lower limb muscle strength, and physical performance in older adults. The review also provides directions for future research. We noted contrasting findings for an association between HGS, lower limb strength, and physical performance. We found insufficient evidence for endorsing the handgrip dynamometer as a definitive tool for measuring overall muscle strength and physical function. More evidence is needed from comparable studies involving larger samples of men and women and investigating other areas such as lifestyle, daily physical activity levels, and health-related disorders.

Prediction of probable sarcopenia with an alternative method: plantar flexion strength

OBJECTIVE

Sarcopenia is a geriatric syndrome characterized by age-related reduction in muscle mass and strength. Assessment of handgrip strength (HGS) is an essential measurement for the diagnosis of sarcopenia; however, disorders affecting upper limb muscles and joints may pose challenges in assessing handgrip strength. Therefore, the present study aimed to show the validity of plantar flexion strength (PFS) in diagnosing probable sarcopenia and investigating the relations between comprehensive geriatric assessment (CGA) and PFS while determining appropriate cutoff values for PFS.

METHODS

A total of 304 older participans who underwent CGA were included. The revised criteria of the European Working Group on Sarcopenia in Older People (EWGSOP) were used to determine PFS cutoff values for gender groups. Associations between probable sarcopenia and CGA parameters were investigated using PFS cutoffs.

RESULTS

The mean age was 74.50 ± 7.10, and 170 of the participants (55.9%) were women. The mean HGS was 14.40 ± 5.63 kg in women and 25.08 ± 8.07 kg in men. The mean PFS were 13.17 ± 3.62 and 14.92 ± 3.86 kg respectively. In females, PFS cutoff with sensitivity/specificity; 0.81/0.60 was set at 14.95 kg (AUC 0.69, 95%CI: 0.611-0.772, p < 0.001). In males, PFS cutoff with sensitivity/specificity; 0.80/0.55 was set at 16.80 kg (AUC 0.68, 95%CI: 0.593-0.772, p < 0.001). Probable sarcopenia identified by GMS was associated with basic living activities, mobility, and frailty after adjusting for age and sex (p < 0.001, p = 0.021, and p = 0.011 respectively).

CONCLUSIONS

Probable sarcopenia identified by PFS could be associated with CGA. PFS may be useful for evaluating probable sarcopenia in older adults whose HGS cannot be estimated accurately.

Age-related fatigability in knee extensors and knee flexors during dynamic fatiguing contractions

This study investigated the effects of dynamic knee extension and flexion fatiguing task on torque and neuromuscular responses in young and older individuals. Eighteen young (8 males; 25.1 ± 3.2 years) and 17 older (8 males; 69.7 ± 3.7 years) volunteered. Following a maximal voluntary isometric contraction test, participants performed a fatiguing task involving 22 maximal isokinetic (concentric) knee extension and flexion contractions at 60°/s, while surface EMG was recorded simultaneously from the knee extensors (KE) and flexors (KF). Fatigue-induced relative torque reductions were similar between age groups for KE (peak torque decrease: 25.15% vs 26.81%); however, KF torque was less affected in older individuals (young vs older peak torque decrease: 27.6% vs 11.5%; p < 0.001) and this was associated with greater increase in hamstring EMG amplitude (p < 0.001) and hamstrings/quadriceps peak torque ratio (p < 0.01). Furthermore, KE was more fatigable than KF only among older individuals (peak torque decrease: 26.8% vs 11.5%; p < 0.001). These findings showed that the age-related fatigue induced by a dynamic task was greater for the KE, with greater age-related decline in KE compared to KF.

The impact of diabetic neuropathy on the distal versus proximal comparison of weakness in lower and upper limb muscles of patients with type 2 diabetes mellitus: a cross-sectional study

OBJECTIVES

This study aimed to determine the impact of diabetic neuropathy (dNP) on the distal versus proximal comparison of weakness in lower and upper limb muscles of patients with type 2 Diabetes Mellitus (T2DM).

METHODS

19 healthy male controls without neuropathy (HC) and 35 male T2DM patients, without dNP (n=8), with sensory dNP (n=13) or with sensorimotor dNP (dNPsm; n=14), were enrolled in this study. Maximal isometric (IM) and isokinetic (IK) muscle strength and IK muscle endurance of the dominant knee, ankle and elbow, and maximal IM handgrip strength were measured by means of dynamometry.

RESULTS

Ankle muscle endurance was lower compared to the knee, independently of dNP (p<0.001). Maximal IK ankle muscle strength was also lower compared to the knee, albeit only in dNPsm (p=0.003). No differences were found between maximal IM handgrip and elbow strength.

CONCLUSIONS

Our results suggest an impact of T2DM -with or without dNP- on lower limb muscle strength more distally than proximally, while this was not observed in the upper limb. The gradient of dNP seemed to be a determining factor for the maximal muscle strength, and not for muscle endurance, in the lower limb.

Distinct Trajectories of Individual Physical Performance Measures Across 9 Years in 60- to 70-Year-Old Adults

Background

Physical performance is an important factor for successful aging. This study aimed to identify distinct trajectories of multiple physical performance measures over 9 years in individuals aged 60–70 years and to evaluate their characteristics and the overlap between measures.

Methods

Four physical performance measures were assessed in 440 participants of the Longitudinal Aging Study Amsterdam: tandem stand, gait speed, chair stand, and handgrip strength. Gender-specific latent class models were conducted to obtain distinct trajectories and their degree of overlap.

Results

Mean age at baseline was 67.9 (SD 1.7) years for males and 68.0 (SD 1.7) years for females. The optimal number of trajectories differed across measures. For tandem stand, no distinct trajectories were found (all 179 males, 198 females). For gait speed, three trajectories were identified, dependent on baseline speed: high-stable (47 males, 27 females), intermediate-stable (132 males, 130 females), and low-declining performance (6 males, 48 females). Two trajectories were identified for the chair stand: a stable (168 males, 150 females) and declining trajectory (10 males, 38 females). For handgrip strength, three declining trajectories were identified differing in baseline performance: high (55 males, 75 females), intermediate (111 males, 118 females), and low (17 males, 10 females). Overall, 11.9% of males and 5.7% of females were classified in similar trajectories across measures.

Conclusions

Trajectories of physical performance were heterogeneous, but showed similar patterns for males and females. Little overlap between measures was shown, suggesting different mechanisms for decline. This study emphasizes the use of multiple domains to assess physical performance.

A Comparison of Load-Velocity and Load-Power Relationships Between Well-Trained Young and Middle-Aged Males During Three Popular Resistance Exercises

Fernandes, JFT, Lamb, KL, and Twist, C. A comparison of load-velocity and load-power relationships between well-trained young and middle-aged males during 3 popular resistance exercises. J Strength Cond Res 32(5): 1440-1447, 2018-This study examined the load-velocity and load-power relationships among 20 young (age 21.0 ± 1.6 years) and 20 middle-aged (age 42.6 ± 6.7 years) resistance-trained males. Participants performed 3 repetitions of bench press, squat, and bent-over-row across a range of loads corresponding to 20-80% of 1 repetition maximum (1RM). Analysis revealed effects (p < 0.05) of group and load × group on barbell velocity for all 3 exercises, and interaction effects on power for squat and bent-over-row (p < 0.05). For bench press and bent-over-row, the young group produced higher barbell velocities, with the magnitude of the differences decreasing as load increased (ES; effect size 0.0-1.7 and 1.0-2.0, respectively). Squat velocity was higher in the young group than the middle-aged group (ES 1.0-1.7) across all loads, as was power for each exercise (ES 1.0-2.3). For all 3 exercises, both velocity and 1RM were correlated with optimal power in the middle-aged group (r = 0.613-0.825, p < 0.05), but only 1RM was correlated with optimal power (r = 0.708-0.867, p < 0.05) in the young group. These findings indicate that despite their resistance training, middle-aged males were unable to achieve velocities at low external loads and power outputs as high as the young males across a range of external resistances. Moreover, the strong correlations between 1RM and velocity with optimal power suggest that middle-aged males would benefit from training methods which maximize these adaptations.

Handgrip Strength Cannot Be Assumed a Proxy for Overall Muscle Strength

OBJECTIVES

Dynapenia, low muscle strength, is predictive for negative health outcomes and is usually expressed as handgrip strength (HGS). Whether HGS can be a proxy for overall muscle strength and whether this depends on age and health status is controversial. This study assessed the agreement between HGS and knee extension strength (KES) in populations differing in age and health status.

DESIGN

Data were retrieved from 5 cohorts.

SETTING AND PARTICIPANTS

Community, geriatric outpatient clinics, and a hospital. Five cohorts (960 individuals, 49.8% male) encompassing healthy young and older individuals, geriatric outpatients, and older individuals post hip fracture were included.

MEASURES

HGS and KES were measured according to the protocol of each cohort. Pearson correlation was performed to analyze the association between HGS and KES, stratified by sex. HGS and KES were standardized into sex-specific z scores. The agreement between standardized HGS and standardized KES at population level and individual level were assessed by intraclass correlation coefficients (ICC) and Bland-Altman analysis.

RESULTS

Pearson correlation coefficients were low in healthy young (male: 0.36 to 0.45, female: 0.45) and healthy older individuals (male: 0.35 to 0.37, female: 0.44), and moderate in geriatric outpatients (male and female: 0.54) and older individuals post hip fracture (male: 0.44, female: 0.57) (P < .05, except for male older individuals post hip fracture [P = .07]). Intraclass correlation coefficient values were poor to moderate in all populations (ie, healthy young individuals [0.41, 0.45], healthy older individuals [0.37, 0.41, 0.44], geriatric outpatients [0.54], and older individuals post hip fracture [0.54]). Bland-Altman analysis showed that within the same population of age and health status, agreement between HGS and KES varied on individual level.

CONCLUSIONS

At both population and individual level, HGS and KES showed a low to moderate agreement independently of age and health status. HGS alone should not be assumed a proxy for overall muscle strength.

Normative values of isometric elbow strength in healthy adults: a systematic review

BACKGROUND

Post-traumatic deformities such as biceps tendon rupture or (peri-)articular fractures of the elbow are often related to a decrease in muscle strength. Postoperative evaluation of these deformities requires normative values of elbow strength. The purpose of this systematic review was to determine these normative values of isometric elbow strength in healthy adults resulting from studies evaluating this strength (i.e. flexion, extension, pronation and supination strength).

METHODS

The databases of PubMed, EMBASE and Web of Sciences were searched and screened for studies involving the isometric elbow strength as measured in asymptomatic volunteers. The quality of the studies was assessed and studies of low quality were excluded.

RESULTS

Nineteen studies met the inclusion criteria and were of sufficiently high quality to be included in the present review. In these studies, elbow strength was measured in a total of 1880 healthy volunteers. The experimental set-up and devices used to measure elbow strength varied between studies. Using some assumptions, a normative values table was assembled.

CONCLUSIONS

Large standard deviations of normative values in combination with different measurement devices used, as well as the different measurement positions of the subjects, demonstrated that there is no consensus about measuring the isometric elbow strength and therefore the normative values have to be interpreted with caution.

Selected B vitamins and their possible link to the aetiology of age-related sarcopenia: relevance of UK dietary recommendations

The possible roles of selected B vitamins in the development and progression of sarcopenia are reviewed. Age-related declines in muscle mass and function are associated with huge and increasing costs to healthcare providers. Falls and loss of mobility and independence due to declining muscle mass/function are associated with poor clinical outcomes and their prevention and management are attractive research targets. Nutritional status appears a key modifiable and affordable intervention. There is emerging evidence of sarcopenia being the result not only of diminished anabolic activity but also of declining neurological integrity in older age, which is emerging as an important aspect of the development of age-related decline in muscle mass/function. In this connection, several B vitamins can be viewed as not only cofactors in muscle synthetic processes, but also as neurotrophic agents with involvements in both bioenergetic and trophic pathways. The B vitamins thus selected are examined with respect to their relevance to multiple aspects of neuromuscular function and evidence is considered that requirements, intakes or absorption may be altered in the elderly. In addition, the evidence base for recommended intakes (UK recommended daily allowance) is examined with particular reference to original datasets and their relevance to older individuals. It is possible that inconsistencies in the literature with respect to the nutritional management of sarcopenia may, in part at least, be the result of compromised micronutrient status in some study participants. It is suggested that in order, for example, for intervention with amino acids to be successful, underlying micronutrient deficiencies must first be addressed/eliminated.

Circuit resistance training is an effective means to enhance muscle strength in older and middle aged adults: A systematic review and meta-analysis

BACKGROUND

Physical exercise, particularly resistance training (RT), is proven treatment to reduce the accelerated decline in muscle strength exhibited by older adults, but its effect is hindered by low adherence rate, even under well-structured programs.

OBJECTIVE AND DATA SOURCES

We investigated the efficacy of circuit resistance training (CRT) on muscle strength, lean mass and aerobic capacity in older adults based on report in MEDLINE, EMBASE, ClinicalTrials.gov and Cochrane electronic (through 8/2016).

STUDY ELIGIBILITY CRITERIA

middle and older aged men and/or women who followed a structured program, assigned to CRT.

STUDY APPRAISAL AND SYNTHESIS METHODS

Out of 237 originally identified articles, 10 articles were included with a total of 362 patients with mean: age -64.5±7.4 years; 3±1.15 sessions/week; session duration 41.8±15.9min.

RESULTS

Upper body strength modestly increased, by 1.14kg (95% CI; 0.28-2.00), whereas larger increment was seen in lower body strength (11.99; 2.92-21.06). Higher program volume (>24 sessions) positively influenced upper body strength and aerobic capacity.

LIMITATIONS

(1) variability in the studies' validity; (2) relatively low number of studies.

CONCLUSION

CRT is a valid alternative to conventional RT. Its shorter duration and lower intensity relative to traditional RT, may increase adherence to training in older adults.

Superior Effects of Eccentric to Concentric Knee Extensor Resistance Training on Physical Fitness, Insulin Sensitivity and Lipid Profiles of Elderly Men

It has been reported that eccentric training of knee extensors is effective for improving blood insulin sensitivity and lipid profiles to a greater extent than concentric training in young women. However, it is not known whether this is also the case for elderly individuals. Thus, the present study tested the hypothesis that eccentric training of the knee extensors would improve physical function and health parameters (e.g., blood lipid profiles) of older adults better than concentric training. Healthy elderly men (60–76 years) were assigned to either eccentric training or concentric training group (n = 13/group), and performed 30–60 eccentric or concentric contractions of knee extensors once a week. The intensity was progressively increased over 12 weeks from 10 to 100% of maximal concentric strength for eccentric training and from 50 to 100% for concentric training. Outcome measures were taken before and 4 days after the training period. The results showed that no sings of muscle damage were observed after any sessions. Functional physical fitness (e.g., 30-s chair stand) and maximal concentric contraction strength of the knee extensors increased greater (P ≤ 0.05) after eccentric training than concentric training. Homeostasis model assessment, oral glucose tolerance test and whole blood glycosylated hemoglobin showed improvement of insulin sensitivity only after eccentric training (P ≤ 0.05). Greater (P ≤ 0.05) decreases in fasting triacylglycerols, total, and low-density lipoprotein cholesterols were evident after eccentric training than concentric training, and high-density lipoprotein cholesterols increased only after eccentric training. These results support the hypothesis and suggest that it is better to focus on eccentric contractions in exercise medicine.

Age differences in dynamic fatigability and variability of arm and leg muscles: Associations with physical function

INTRODUCTION

It is not known whether the age-related increase in fatigability of fast dynamic contractions in lower limb muscles also occurs in upper limb muscles. We compared age-related fatigability and variability of maximal-effort repeated dynamic contractions in the knee extensor and elbow flexor muscles; and determined associations between fatigability, variability of velocity between contractions and functional performance.

METHODS

35 young (16 males; 21.0±2.6years) and 32 old (18 males; 71.3±6.2years) adults performed a dynamic fatiguing task involving 90 maximal-effort, fast, concentric, isotonic contractions (1 contraction/3s) with a load equivalent to 20% maximal voluntary isometric contraction (MVIC) torque with the elbow flexor and knee extensor muscles on separate days. Old adults also performed tests of balance and walking endurance.

RESULTS

Old adults had greater fatigue-related reductions in peak velocity compared with young adults for both the elbow flexor and knee extensor muscles (P<0.05) with no sex differences (P>0.05). Old adults had greater variability of peak velocity during the knee extensor, but not during the elbow flexor fatiguing task. The age difference in fatigability was greater for the knee extensor muscles (35.9%) compared with elbow flexor muscles (9.7%, P<0.05). Less fatigability of the knee extensor muscles was associated with greater walking endurance (r=-0.34, P=0.048) and balance (r=-0.41, P=0.014) among old adults.

CONCLUSIONS

An age-related increase in fatigability of a dynamic fatiguing task was greater for the knee extensor compared with the elbow flexor muscles in males and females, and greater fatigability was associated with lesser walking endurance and balance.

Dor muscular e atividade de creatina quinase após ações excêntricas: uma análise de cluster

INTRODUÇÃO: O exercício excêntrico máximo promove queda da capacidade de geração de força, aumento de dor muscular de início tardio (DMIT) e extravasamento de creatina quinase (CK) no sangue. No entanto, essas respostas ao exercício excêntrico demonstram alta variabilidade interindivíduos.OBJETIVOS: Classificar e analisar essas respostas segundo a vulnerabilidade individual, por meio da magnitude da redução dos níveis de força após exercício excêntrico.MÉTODOS: Dezoito sujeitos (11 homens e sete mulheres com idade entre 18 e 71 anos) saudáveis realizaram cinco séries de seis ações excêntricas máximas para flexores do cotovelo em dinamômetro isocinético (90°s-1, amplitude de movimento de 80 a 20°). Foram analisadas contração voluntária muscular concêntrica máxima (CVM), DMIT e CK pré, pós (exceto CK), 24 h, 48 h, 72 h e 96 h após o protocolo. Os indivíduos foram classificados como "baixos" (BR) e "altos" respondedores (AR) ao pico de queda de CVM pós-exercício seguindo-se uma análise de cluster e comparação entre grupos para CVM, DMIT e CK com teste-t independente.RESULTADOS: A comparação entre BR e AR indicou maiores valores de queda de CVM para o grupo AR (AR: -30,7 ± 3,3%; BR: -14,1 ± 2,2%, p< 0,001) e maior DMIT também para o grupo AR (AR: 33,0 ± 8,6 mm; BR: 10,2 ± 2,5 mm, p= 0,033); no entanto, os valores de pico de atividade de CK não diferiram entre os grupos (AR: 232,1 ± 54,8 UI.L-1; BR: 306,1 ± 82,3 UI.L-1, p= 0,490).CONCLUSÃO: A classificação dos indivíduos em grupos de baixos e altos respondedores foi importante para demonstrar que o grupo mais responsivo à queda de força após exercício excêntrico também evidencia maiores níveis de DMIT; contudo, para a CK essa relação não pôde ser estabelecida.