Maximal Isometric Grip Strength Research Articles

Characterization of muscle strength and mobility in oculopharyngeal muscular dystrophy.

Muscle weakness, and its association with mobility limitations, has received little study in oculopharyngeal muscular dystrophy (OPMD) using quantitative and standardized assessments. The objectives of this study were to (1) document upper and lower limb muscle strength, upper limb functions, fatigue, and mobility capacities; (2) compare them with reference values and across participant age groups; and (3) explore associations between muscle strength, fatigue, and mobility capacities among adults with OPMD. Thirty-four participants were included in this cross-sectional study. The following variables were assessed: quantitative maximal isometric muscle strength, grip and pinch strength, fatigue, walking speed, walking endurance, sit-to-stand, and stair ascent and descent capacities. Muscle strength was lower for older than younger participants for five muscle groups (P < .05). Walking endurance, sit-to-stand, stairs (ascent and descent), and strength of hip flexion, grip, and pinch were below 80% of reference values in participants ≥56 y old (55.3%-78.2%). Moderate to strong correlations were found between muscle strength and mobility capacities (ρ = 0.42-0.80, P < .05), and between fatigue and either muscle strength or mobility capacities (ρ = 0.42-0.75, P < .05). This study highlights the impact of OPMD on strength, endurance, and functional capacity, among others, with patients being well below reference values even before the age of 65 y. In addition to helping health professionals to offer better clinical guidance, these results will improve clinical trial readiness. The next steps will be to assess the metrological properties of outcome measures and continue to document the disease progression rate.

Comparing the associations between muscle strength, walking speed, and mortality in community-dwelling older adults of two birth cohorts born 28 years apart

Reduced age-specific mortality and increased muscle strength and walking speed of current older adults may have altered the relationships between these factors as more people may be above the reserve capacity threshold. We compared the cross-sectional associations between muscle strength and walking speed, and the associations of muscle strength and walking speed with five-year mortality between two population-based cohorts of 75- and 80-year-old people born 28 years apart. Maximal isometric grip and knee extension strength and walking speed were measured in 2017–2018 (n = 726). Mortality was ascertained from registers. The associations were compared with data of same-aged people studied in 1989–1990 with identical protocols (n = 500). The knee extension strength-walking speed relationship showed plateauing at higher strength levels among the later-born men, whereas the earlier-born men and women of both cohorts with lower strength levels were on the linear part of the curve. In the later-born women with lower five-year mortality rate (1.16 vs. 5.88 per 100 person-years), the association between grip strength and mortality was markedly different from the earlier cohort (HR 1.13 [95% CI 0.47–2.70] vs. 0.57 [0.37–0.86]). For knee extension strength and walking speed, the mortality hazards were similar between the cohorts, although statistically non-significant in the later-born women. In men, the later-born cohort showed similar associations as observed in the earlier-born cohort despite having lower mortality rate (2.93 vs. 6.44). Current older adults have more functional reserve that will likely help them to maintain walking ability for longer while also contributing to better survival.

Characteristics of Older Patients with Heart Failure Readmitted due to Acute Exacerbations within the Past Year.

We aimed to examine the relationship between physical performance and readmission among older patients with heart failure (HF) over the past year. This retrospective cohort study included 325 patients with HF who were aged ≥65 years and were hospitalized for acute exacerbation between November 2017 and December 2021. We investigated age, sex, body mass index, length of hospital stay, initiation of rehabilitation, New York Heart Association (NYHA) class, Charlson comorbidity index (CCI) score, medications, cardiac/renal function, nutrition, maximal quadriceps isometric strength, grip strength, and Short Physical Performance Battery (SPPB) score. Data were analyzed using the χ2 test, Mann-Whitney U test, and logistic regression analysis. Altogether, 108 patients met the inclusion criteria and were divided into the non-readmission (n = 76) and readmission (n = 32) groups. The readmission group exhibited longer hospital stay, more severe NYHA class, higher CCI score, higher brain natriuretic peptide (BNP) levels, lower muscle strength, and lower SPPB score compared to the non-readmission group. In the logistic regression model, BNP level and SPPB score were independent factors associated with readmission. BNP level and SPPB score were associated with readmission in patients with HF within the past year.

Body composition and physical fitness in adults born small for gestational age at term: a prospective cohort study

There is lack of research on body composition and physical fitness in individuals born small for gestational age (SGA) at term entering mid-adulthood. We aimed to investigate these outcomes in adults born SGA at term. This population-based cohort study included 46 adults born SGA with birth weight < 10th percentile at term (gestational age ≥ 37 weeks) (22 women, 24 men) and 61 adults born at term with birth weight ≥ 10th percentile (35 women, 26 men) at 32 years. Body composition was examined anthropometrically and by 8-polar bioelectrical impedance analysis (Seca® mBCA 515). Fitness was measured by maximal isometric grip strength by a Jamar hand dynamometer, 40-s modified push-up test and 4-min submaximal step test. Participants born SGA were shorter than controls, but other anthropometric measures did not differ between the groups. Men born SGA had 4.8 kg lower grip strength in both dominant (95% CI 0.6 to 9.0) and non-dominant (95% CI 0.4 to 9.2) hand compared with controls. Grip strength differences were partly mediated by height. In conclusion, body composition and physical fitness were similar in adults born SGA and non-SGA at term. Our finding of reduced grip strength in men born SGA may warrant further investigation.

The Effect Of Isometric Hand-grip Exercise With Blood Flow Restriction On Hemodynamic Responses

Several studies have examined the effect of isometric handgrip exercise at submaximal intensities on cardiovascular system. However, few studies have focused on hemodynamic responses and muscle fatigue while exercising with blood flow restriction (BFR). PURPOSE: This crossover study examined the hemodynamic responses and muscle fatigue of an isometric, low intensity hand grip exercise protocol performed under blood flow restriction. METHODS: Twenty-four healthy adult volunteers (12 women and 12 men, age: 23.3 ± 1.9, BMI: 24.9 ± 6.2 kg/m2) performed 4 sessions of isometric hand grip exercise at 30% of maximal isometric strength using a grip dynamometer. Each session lasted 2 min and was performed in two conditions, without (control-C) and with blood flow restriction- BFR on different days. Blood flow restriction was achieved by applying a blood flow restriction cuff at a pressure of 140 mmHg. Hemodynamic responses (systolic and diastolic arterial blood pressure-SBP and DBP, heart rate-HR, and oxygen saturation- OS SpO2) and muscle fatigue (maximal isometric grip strength- IMVC and Borg scale) were assessed before, at the end of each exercise session, and 15 minutes after exercise performed under the two different conditions. Two-way ANOVA with repeated measures was used for statistics and data are given as mean(SD). RESULTS: Outcomes measures mean score (SD) for each time point of measurement in the two exercise conditions.* Between groups significant comparisons in the post hoc testing. BFRT: Blood Flow Restriction Training, Control: Conduction of exercise with no blood restriction, HR: Heart Rate, SBP: Systolic Blood Pressure, DBP: Diastolic Blood Pressure, OS: Oxygen Saturation, IMVC: Isometric Maximal Voluntary Contraction CONCLUSIONS: A submaximal isometric hand grip exercise does not induce significant hemodynamic changes, though it causes a more intense feeling of fatigue.

Grip strength, functional range and anthropometric dimensions, and indication on fulfilling occupations in the home and workplace: A cross-sectional study

Introduction Little is known about the relationship between the types of grip strength, functional range, anthropometric measures, and function in the home and workplace. The study aimed to determine their relationships and explore their contributions to performing usual work duties and overall function in participants with and without hand and wrist injury. Method Forty-four participants were measured on Maximal Voluntary Isometric Grip Strength, Rapid Exchange Grip Contractions and Isometric Endurance, Forearm Length and Volumetry, and the Dart Thrower’s Motion (DTM) measure. They completed the Patient Rated Wrist and Hand Evaluation and the Disabilities of the Arm, Shoulder and Hand Work Module. Results The grip measures significantly correlated with Volumetry (r = 0.62–0.74) in participants with and without hand and wrist injury. The Isometric Endurance and DTM measure of the non-injured hand were found to be contributing factors for participants with hand and wrist injury when returning to usual work duties and overall function. Conclusion The non-injured hand function plays a role in the overall function for participants with hand and wrist injuries. Isometric Endurance and DTM measure could assist clinicians in determining suitable rehabilitation targets, resulting in a better function required for occupations in the home or workplace.

The effect of custom-fitted compression garments worn overnight for recovery from judo training in elite athletes

ABSTRACT This study investigated the effects of custom-fitted compression garments (CG) worn during recovery over a multi-day training camp in elite judo players (judoka). A single blind, placebo-controlled study was carried out in 11 elite judoka, using a two-way crossover design. Two three-day training camps were completed in CG and placebo conditions in a random order. Changes in performance and physiological markers were compared between conditions. Judoka were assessed before training for (maximal) isometric knee extension and grip strength, countermovement jump performance and bench-press velocity, alongside soreness, limb circumferences, plasma creatine kinase activity (CK) and perceived bruising. Measurements were repeated after 12, 36 and 43 h of training, whereupon judoka rated the effectiveness of each intervention. Knee extension and bench-press performance demonstrated significant familiarization (p < 0.001), and were excluded from subsequent analysis. Jump performance was unaffected by training (p > 0.05). Grip strength declined throughout training (p < 0.001), with peak decrements of −9.7% indicating mild muscle damage. Increases in bruising, CK and soreness demonstrated highly variable, if significant (p < 0.001) responses. Although CG were perceived as significantly more effective than placebo for recovery (p = 0.046), no effects were observed for any other outcome (p > 0.05). Compression conferred no statistically significant impact upon recovery markers in elite judoka throughout training. Muscle damage responses were inconsistent in this population. Individual athletes would be advised to monitor habitually-used performance measures while using CG to ascertain whether perceptual benefits translate into enhanced recovery. Highlights Compression garments were perceived as more effective for recovery than placebo by elite judoka. However, no measures of performance or muscle damage were enhanced by CG. Randori was associated with inconsistent muscle damage responses in elite judoka, while lower-body performance was not impaired. Individual athletes would be advised to monitor habitually-used performance measures while using CG to ascertain whether perceptual benefits translate into enhanced recovery.

The Female Menstrual Cycles Effect on Strength and Power Parameters in High-Level Female Team Athletes.

PurposeThe female menstrual cycle (MC) is characterized by hormonal fluctuations throughout its different phases. However, research regarding its effect on athletic performance in high level athletes is sparse. The aim of this study was to (i) investigate the female MCs effect on strength and power performance in highly trained female team athletes throughout the MC and (ii) examine whether eumenorrheic participants with natural hormonal fluctuations displayed enhanced performance in the follicular phase (FP) versus the luteal phase (LP), compared to controls using hormonal contraceptives.Materials and MethodsA total of 29 athletes (Age 21.2 ± 3.3 years; weight 65.6 ± 8.7 kg; height 170.2 ± 8.0 cm; and fat free mass 52.7 ± 7.1) completed the study after a 6-week testing period (8 eumenorrheic participants and 21 hormonal contraceptive controls). Participants were recruited from the team sports soccer, handball and volleyball. Testing protocol consisted of maximal voluntary isometric grip strength, 20-m sprint, countermovement jump and pneumatic leg-press. Based on self-reported use of hormonal contraceptives, participants were divided into non-hormonal contraceptive group and hormonal contraceptive group, the latter working as a control group. Differences in performance between the FP and LP were investigated. MC phase was confirmed by serum hormonal levels through venous blood samples in the non-hormonal contraceptive group.ResultsThere were no statistically significant changes for the two different phases of the MC, in terms of physical performance for the whole group. Further, there was no significant difference between groups during the MC for any of the outcome variables, maximal voluntary isometric grip strength F(3.29) = 0.362; 20-m sprint F(3.24) = 0.710; countermovement jump F(3.26) = 2.361; and leg-press F(3.26) = 1.746.ConclusionIn high level female team athletes, no difference in performance was observed based on hormonal contraceptive status. This suggests that the MC does not alter acute strength and power performance on a group level in high level team athletes.

Effectiveness of Unihemispheric Concurrent Dual-Site Stimulation over M1 and Dorsolateral Prefrontal Cortex Stimulation on Pain Processing: A Triple Blind Cross-Over Control Trial.

Background: Transcranial direct current stimulation (tDCS) of the motor cortex (M1) produces short-term inhibition of pain. Unihemispheric concurrent dual-site tDCS (UHCDS-tDCS) over the M1 and dorsolateral prefrontal cortex (DLPFC) has greater effects on cortical excitability than when applied alone, although its effect on pain is unknown. The aim of this study was to test if anodal UHCDS-tDCS over the M1 and DLPFC in healthy participants could potentiate conditioned pain modulation (CPM) and diminish pain temporal summation (TS). Methods: Thirty participants were randomized to receive a sequence of UHCDS-tDCS, M1-tDCS and sham-tDCS. A 20 min 0.1 mA/cm2 anodal or sham-tDCS intervention was applied to each participant during three test sessions, according to a triple-blind cross-over trial design. For the assessment of pain processing before and after tDCS intervention, the following tests were performed: tourniquet conditioned pain modulation (CPM), pressure pain temporal summation (TS), pressure pain thresholds (PPTs), pressure pain tolerance, mechanosensitivity and cold hyperalgesia. Motor function before and after tDCS intervention was assessed with a dynamometer to measure maximal isometric grip strength. Results: No statistically significant differences were found between groups for CPM, pressure pain TS, PPT, pressure pain tolerance, neural mechanosensitivity, cold hyperalgesia or grip strength (p > 0.05). Conclusions: Neither UHCDS-tDCS nor M1-tDCS facilitated CPM or inhibited TS in healthy subjects following one intervention session.

Evaluation of Maximal Isometric Hand Grip Strength in Different Sports

Background: Grip strength has proven to have a positive effect on sports performance in which a sportimplement is grasped in the hand.Objective: To compare Hand Grip Strength in males of different sports.Materials and Methods: 400 male sportsmen, 100 in each sport (Cricket, Hockey, Tennis and Badminton)aged 18-25 yrs volunteered to participate in this study were engaged. Each participant was asked to performat least three maximal isometric grip strength measurements using a Jamar Handgrip Dynamometer and theaverage of the three grip strength trials readings was recorded.Statistical analysis: R-Programming Language Software was applied for statistical analyses of the data; theresults were statistically analyzed by ANOVA.Results: The findings of the present study showed that the maximum grip strength measured in both handsis higher in Cricket players than in Hockey, Tennis and Badminton players (P&lt;0.05).Conclusion: In the present study hand grip strength might have increased due to regular training. It wouldbe beneficial to the sportsmen in terms of optimizing training programs separately for particular sports.

Grip Strength-Endurance in Ambitious and Recreational Climbers: Does the Strength Decrement Index Serve as a Feasible Measure?

The present study investigated the time course of repetitive maximal isometric grip strength, depending on the arm position, laterality (dominant vs. non-dominant side), and climbing level. The intervention aimed to provide a feasible indicator of maximal strength-endurance in climbing. Seventeen recreational (climbing level (CL): 6.8 (SD 0.5) on the Union Internationale des Associations d’Alpinisme (UIAA) metric scale) and eleven ambitious (CL: 8.7 (SD 0.6) UIAA metric scale) climbers (age: 27 (8) years; BMI: 21.6 (1.9) kg/m2; ape index (arm span divided by body height): 1.05 (0.18); training volume: 2.2 (1.0) h/week). Participants completed maximal isometric handgrip strength (Fmax) tests in four positions (left and right hand beside the trunk as well as left and right hand above the shoulder) plus twelve repetitive work-relief cycles, lasting 4 and 1 s where isometric strength, heart rate, and perceived exertion were recorded. Fmax differed between groups in nearly all positions. A large side × position × time × group interaction was observed for repetitive isometric grip strength (p = 0.009, ηp2 = 0.71). However, subsequent post-hoc tests did not reveal a significant difference between groups during each testing position. Additional correlation analysis between asymmetry and CL showed an inverse relationship for ambitious climbers (r = −0.71). In conclusion, the degree of grip strength decline did not relevantly differentiate between ambitious and recreational climbers. Thus, the time course of handgrip strength seems to mainly rely on maximal grip strength during the first contraction.

Mortality Risk Among Older People Who Did Versus Did Not Sustain a Fracture: Baseline Prefracture Strength and Gait Speed as Predictors in a 15-Year Follow-Up.

Physiological reserve, as indicated by muscle strength and gait speed, may be especially determinant of survival in people who are exposed to a health stressor. We studied whether the association between strength/speed and mortality risk would be stronger in the time period after a fracture compared to other time periods. Participants were population-based sample of 157 men and 325 women aged 75 and 80 years at baseline. Maximal 10-m gait speed and maximal isometric grip and knee extension strength were tested at the baseline before the fracture. Subsequent fracture incidence and mortality were followed up for 15 years. Cox regression analysis was used to estimate fracture time-stratified effects of gait speed and muscle strength on mortality risk in three states: (i) nonfracture state, (ii) the first postfracture year, and (iii) after the first postfracture year until death/end of follow-up. During the follow-up, 20% of the men and 44% of the women sustained a fracture. In both sexes, lower gait speed and in women lower knee extension strength was associated with increased mortality risk in the nonfracture state. During the first postfracture year, the mortality risk associated with slower gait and lower strength was increased and higher than in the nonfracture state. After the first postfracture year, mortality risk associated with lower gait speed and muscle strength attenuated. Lower gait speed and muscle strength were more strongly associated with mortality risk after fracture than during nonfracture time, which may indicate decreased likelihood of recovery.

The Effect of Stretching and Strengthening Exercise in the Management of Lateral Epicondylitis

Background: Lateral Epicondylitis (LE) is a common overuse injury of Elbow that generates pain over the lateral aspect of elbow. LE is one of the most common causes of elbow and forearm pain encountered in clinical practice commonly associated with resistant wrist or finger extension and gripping activities. The management of LE is enlightened by various form physical modalities and therapeutic exercise like stretching and strengthening exercise. The purpose of this prospective study was to investigate the effects of stretching and strengthening exercises on pain and grip strength of LE. Materials and methods : Eighty patients were enrolled, non-randomized, and divided into 2 groups an experimental Group-A of 40 (44.5 ± 1.5 years) whose receive therapeutic exercise in the form of stretching and strengthening of common extensor forearm muscle and a control Group-B of 40 (41.4 ±2.5 years). Study duration was about one year. Both Group received UST over the lateral aspect of elbow with the 3MHz frequency and 0.5 watt/cm2 intensity for 5 min three sessions per week for six weeks. They were evaluated at every weeks of treatment for six weeks. Comparison between Group-A and Group-B was done with Wilcoxon Rank sum test and unpaired ttest. Results: By the end of the trial period, statistical data analysis in between the two groups showed a significant improvement in pain scores of VAS and the maximal isometric grip strength at sixth week. Conclusion: This study depicts that therapeutic exercise is more effective in reducing pain and improvement of grip strength. So, stretching and strengthening exercise should be considered as a main therapeutic armamentarium in the management of LE.&#x0D; JCMCTA 2019 ; 30 (1) : 36-42

Anthropometric Obesity Indices, Body Fat Percentage, and Grip Strength in Young Adults with different Physical Activity Levels.

The purposes of this study were to determine whether moderately physically active (MPA) and highly physically active (HPA) male (n = 96, age = 22.5 ± 1.7 years) and female (n = 85, age = 21.3 ± 1.6 years) young adults differed in their anthropometric obesity indices (AOIs), body fat percentage (BF%), and muscular strength, and also to examine the associations between physical activity level (PAL) and the abovementioned variables. Participants were measured for body height and weight, BF%, waist and hip circumferences, and maximal isometric grip strength. According to their PAL, estimated by the short version of the International Physical Activity Questionnaire, they were assigned to MPA and HPA subgroups. Regardless of gender, results indicated that participants in the MPA groups had significantly higher values of body weight, waist and hip circumference, BF%, and BMI than participants in the HPA groups. No significant differences were found between physical activity groups in terms of grip strength. The AOIs and BF% were found to be significantly and negatively correlated with the PAL in both genders. In conclusion, the findings of the study suggest that high habitual physical activity is associated with lower adiposity markers. However, the differences in the hand grip strength of the contrasting activity groups were negligible.

Investigation of grip strength by various body postures and gender in Korean adults

Grip strength is an objective measure of a person's hand functionality and upper limb strength. In Asia, there is a lack of normative data for grip strength among the population, especially in South Korea. The objective of this study was to evaluate the grip strength in various body postures and gender in the adult South Korean population. A total of 100 male and 64 female subjects participated in this study. Their grip strengths were measured using a standard adjustable Jamar handle dynamometer. The results showed that their grip strength differed statistically by gender, handedness, and posture. Their gender and right-hand length were the most significant predictors of their grip strength. The Asian population, including South Korea, showed a lower grip strength than the European and American populations in previous studies. The present study showed that the maximal isometric grip strength is affected by gender, handedness, posture, and population. Thus, gender-, population-, and posture-specific grip strength data are essential for clinical and industrial applications.

The effect on upper extremity functions of cardiac electronic device placement on the dominant hand side.

BackgroundAlthough cardiac implantable electronic device (CIED) implantation is considered to be minor surgery, almost 60% of the patients suffer from shoulder‐related problems a short time after the procedure. The purpose of this study was to determine the possible effects of the preference of the dominant side for CIED implantation on the ipsilateral superior extremity functions.MethodsThe study included a total of 107 patients who had been living with a CIED for >6 months. Patients were separated into two groups according to the dominant hand and side of the CIED. The ipsilateral dominant‐hand group comprised those with a CIED on the same side as the dominant hand and the contralateral dominant‐hand group included patients with the CIED placed on the contralateral side to the dominant hand. Visual analogue scale (VAS) pain score, quick disability of the arm shoulder and hand questionnaire (QuickDASH) and maximum isometric grip strength tests were used to evaluate the upper extremity disabilities.ResultsNo significant difference was determined between the groups in respect of VAS pain scores (P = 0.10), QuickDASH scores (P = 0.21), and limitations of the shoulder joint range of motion (P = 0.192). The maximum isometric grip strength was significantly different in the right hands between two groups (34 [16‐95]‐40 [24‐85]) (P = 0.02).ConclusionThe present study shows that the joint range of motion limitation, pain, and disability of the upper extremity were no different in the affected arm compared to the healthy contralateral side with respect to the placement of the CIED on the dominant or non‐dominant side.

Cross-education Effects After High Versus Low Frequency, Volume-matched Grip Strength Training.

Unilateral strength training can attenuate muscle mass and strength losses in an opposite immobilized limb. Traditional unilateral training programs that yield these cross-education effects cause inter-limb asymmetry by inducing hypertrophy and strength increases in the trained limb. A higher frequency training program with lower per session volume may attenuate trained limb hypertrophy but still yield cross-education effects, lowering inter-limb asymmetry. PURPOSE: To determine the effects of a high frequency (HF) vs. low frequency (LF) volume-matched 4-week isometric grip strength training program on cross-education of strength. METHODS: Nineteen healthy right-handed participants (age 24±5 years) were randomly assigned to one of two groups: HF (n=10) and LF (n=9). Participants were tested twice before and once after a 4-week, unilateral (right) grip strength training program totaling 120 maximal repetitions per week. HF trained twice per day, 5 days per week, 2 sets of 6 repetitions per session. LF trained 3 days per week, 5 sets of 8 repetitions per session. Measures included maximal isometric grip strength (grip dynamometer) and wrist flexion (NORM dynamometer), muscle thickness (ultrasound), muscle activation (EMG) and voluntary activation (twitch-interpolation). RESULTS: A significant time main effect (p<0.001) was observed for isometric grip strength where both limbs increased from pre to post with no differences between groups (LF right: 42.4±12.2 to 46.6±11.1 kg; LF left: 38.6±10.5 to 42.0±10.4 kg; HF right: 47.6±13.6 to 50.5±13.5 kg; HF left: 43.9±11.9 to 47.6±13.3 kg). Muscle thickness significantly increased in both groups in the right limb only (R: 3.93±0.44 to 4.04±0.45 cm, p<0.05; L: 3.88±0.51 to 3.88±0.49 cm, p=0.897). EMG burst activity (normalized to the maximal M wave), maximal isometric wrist flexion torque, and voluntary activation of the forearm muscles did not change significantly from pre to post training in either arm (p=0.256 to 0.831). CONCLUSION: As predicted, both LF and HF training programs were effective for inducing cross-education of grip strength to the untrained limb; however, contrary to our hypothesis, both programs induced similar hypertrophy in the trained limb. These findings have implications for rehabilitation strategies after unilateral injury.

Grip strength measured by high precision dynamometry in healthy subjects from 5 to 80 years.

BackgroundGrip strength is a variable which may be important to measure and follow in various populations. A new dynamometer with high accuracy and sensitivity has recently been developed to assess grip strength. The objectives of this work were to provide norms of maximal isometric grip strength measured with this new dynamometer (the MyoGrip device), to assess the reliability of measurements, to compare the measurements obtained with MyoGrip and Jamar dynamometers and finally to establish predictive equations from a population of healthy subjects (children and adults).MethodsMeasurements of maximal isometric grip strength using the MyoGrip and the Jamar (which is considered as the gold-standard) were performed on 346 healthy subjects aged from 5 to 80 years. Test-retest reliability for both devices was assessed on 77 subjects. Predictive equations were computed on subjects younger than 60 years of age in order to avoid the effects of aging on strength.ResultsThis study provides norms for isometric grip strength for health subjects from 5 to 80 years. Reliability of the MyoGrip device was excellent (intraclass correlation coefficient: 0.967). Despite good correlation between devices, the Jamar tended to overestimate maximal grip strength by about 14 %. A single predictive equation for men and women, adults and children incorporating hand circumference only can be used to compute the predicted theoretical maximal grip strength.ConclusionsThe MyoGrip device is a reliable tool for measuring isometric grip strength. Owing to its unique metrological features, it can be used in very weak patients or in any situation where high precision and accuracy are required.

Physical working capacity at fatigue threshold (PWCFT) is associated with sarcopenia-related body composition and measures of functionality in older adults

The relationship between PWCFT and common measures used to assess sarcopenia in older adults were examined. Fifty-eight older adults [age: 71.1±6.2 years; body mass index (BMI): 28.0±5.4kg/m2] completed the testing procedures. Sarcopenia-related body composition was measured by dual-energy X-ray absorptiometry and participants performed a discontinuous cycle ergometry test to determine PWCFT. Functionality assessments included maximal isometric grip strength (GRIP) and sit-to-stand (STS) repetitions in 30s. Muscle quality (MQ) was defined as GRIP relative to appendicular lean soft tissue (ALM), while skeletal muscle index (SMI) was defined as ALM/height2. Pearson correlations were used to examine the relationships among dependent variables. PWCFT showed significant relationships with ALM (r=0.57), SMI (r=0.47), body fat percentage (BF%) (r=−0.50), GRIP (r=0.49), and STS (r=0.44). For follow-up analyses, study participants were categorized into low sarcopenia risk (n=31) or high sarcopenia risk (n=27) groups by SMI. Sarcopenia risk was associated with PWCFT [odds ratio (OR): 1.051, 95% confidence interval (CI): 1.016–1.087] and STS (OR: 1.305, CI: 1.060–1.607), but not GRIP (OR: 1.098, CI: 0.989–1.218). Using receiver–operator characteristic curve analysis, both PWCFT [area under the curve (AUC): 0.737, CI: 0.608–0.866, optimal cutoff: 37.5W] and STS (AUC: 0.749, CI: 0.623–0.874, optimal cutoff: 12.5 repetitions) showed discriminative ability with regard to sarcopenia risk. The current data suggest that the neuromuscular fatigue threshold, as measured by PWCFT, is related to measures of body composition and function in older adults.

Fitness and physical activity in youth with type 1 diabetes mellitus in good or poor glycemic control

Patients with type 1 diabetes mellitus (T1DM) may experience poor muscle health as a result of chronic hyperglycemia. Despite this, muscle function in children with T1DM with good or poor glycemic control has yet to be examined in detail. To assess differences in muscle-related fitness variables in children with T1DM with good glycemic control (T1DM-G), as well as those with poor glycemic control (T1DM-P), and non-diabetic, healthy controls. Eight children with T1DM-G [glycosylated hemoglobin (HbA1c) ≤ 7.5% for 9 months], eight children with T1DM-P (HbA1c ≥ 9.0% for 9 months), and eight healthy controls completed one exercise session. Anaerobic and aerobic muscle functions were assessed with a maximal isometric grip strength test, a Wingate test, and an incremental continuous cycling test until exhaustion. Blood samples were collected at rest to determine HbA1c at the time of testing. Physical activity was monitored over 7 d using accelerometry. Children with T1DM-P displayed lower peak oxygen consumption (VO2peak ) values (mL/kg/min) compared to healthy controls (T1DM-P: 33.2 ± 5.6, controls: 43.5 ± 6.3, p < 0.01), while T1DM-G (43.5 ± 6.3) had values similar to controls and T1DM-P. There was a negative relationship between VO2peak and HbA1c% (r = -0.54, p < 0.01). All groups were similar in all other fitness variables. There were no group differences in physical activity variables. Children with T1DM-G did not display signs of impaired muscle function, while children with T1DM-P have signs of altered aerobic muscle capacity.