Occupational physical activity, all-cause, cardiovascular disease, and cancer mortality in 349,248 adults: Prospective and longitudinal analyses of the MJ Cohort

Background:Evidence on the health benefits of occupational physical activity(OPA)is inconclusive.We examined the associations of baseline OPA and OPA changes with all-cause,cardiovascular disease(CVD),and cancer mortality and survival times.Methods:This study included prospective and longitudinal data from the MJ Cohort,comprising adults over 18 years recruited in 1998-2016,349,248 adults(177,314 women)with baseline OPA,of whom 105,715(52,503 women)had 2 OPA measures at 6.3±4.2 years(mean±SD)apart.Exposures were baseline OPA,OPA changes,and baseline leisure-time physical activity.Results:Over a mean mortality follow-up of 16.2±5.5 years for men and 16.4±5.4 years for women,11,696 deaths(2033 of CVD and 4631 of cancer causes)in men and 8980 deaths(1475 of CVD and 3689 of cancer causes)in women occurred.Combined moderately heavy/heavy baseline OPA was beneficially associated with all-cause mortality in men(multivariable-adjusted hazard ratio(HR)=0.93,95%confidence interval(95%CI):0.89-0.98 compared to light OPA)and women(HR=0.86,95%CI:0.79-0.93).Over a mean mortality follow-up of 12.5±4.6 years for men and 12.6±4.6 years for women,OPA decreases in men were detrimentally associated(HR=1.16,95%CI:1.01-1.33)with all-cause mortality,while OPA increases in women were beneficially(HR=0.83,95%CI:0.70-0.97)associated with the same outcome.Baseline or changes in OPA showed no associations with CVD or cancer mortality.Conclusion:Higher baseline OPA was beneficially associated with all-cause mortality risk in both men and women.Our longitudinal OPA analyses partly confirmed the prospective findings,with some discordance between sex groups.

Sleep quality improved following a single session of moderate-intensity aerobic exercise in older women:Results from a pilot study

Background： Poor sleep quality is associated with adverse effects on health outcomes. It is not clear whether exercise can improve sleep quality and whether intensity of exercise affects any of the effects. Methods： Fifteen healthy, non-obese （body mass index = 24.4 ± 2.1 kg/m^2, mean 4- SD）, sedentary （〈20 min of exercise on no more than 3 times/week） older women （66.1 ± 3.9 years） volunteered for the study. Peak oxygen consumption （VO2peak） was evaluated using a graded exercise test on a treadmill with a metabolic cart. Following a 7-day baseline period, each participant completed two exercise sessions （separated by 1 week） with equal caloric expenditure, but at different intensities （60% and 45% VO2peak, sequence randomized） between 9：00 and 11：00 am. A wrist ActiGraph monitor was used to assess sleep at baseline and two nights following each exercise session. Results： The average duration of the exercise was 54 and 72 rain, respectively at 60% （moderate-intensity） and 45% VO2peak （light-intensity）. Wake time after sleep onset was significantly shorter （p = 0.016）, the number of awakenings was less （p = 0.046）, and total activity counts were lower （p = 0.05） after the moderate-intensity exercise compared to baseline no-exercise condition. Conclusion： Our data showed that a single moderate-intensity aerobic exercise session improved sleep quality in older women.

Effects of acute aerobic exercise on motor response inhibition:An ERP study using the stop-signal task

Purpose： The purpose of this study was to determine the effects of acute exercise on motor response inhibition using both behavioral and electrophysiological approaches. Methods： The P3 and N1 event-related potential （ERP） components were recorded while performing a stop-signal task in 21 college students following a moderately intense acute exercise bout for 30 min and a sedentary control session that involved reading. Results： Acute exercise induced a shorter stop signal response time （SSRT） as compared to control; however, the go response time （Go RT） remained unchanged. In examining the ERP data, acute exercise increased both P3 amplitude and latency but did not affect the N1 component. Conclusion： Acute exercise has a selective and beneficial effect on cognitive function, specifically affecting the motor response inhibition aspect of executive function. Furthermore, acute exercise predominately impacts later stages of information processing during motor response inhibition, which may lead to an increase in attentional resource allocation and confer the ability to successfully withhold a response to achieve motor response inhibition.

The Effect of Exercise Therapy on Physical Function, Biochemistry and Dialysis Adequacy in Haemodialysis Patients: A Systematic Review and Meta-Analysis

Background:Patients undergoing dialysis have high mortality rates and a unique risk factor profile. Some improvements elicited by exercise training have been shown in dialysis populations, here we aimed to further explore the bene-fits of exercise. As well as changes in physical fitness we quantified cardiac function, depression, serum biochemistry, dialysis adequacy and energy intake following exercise training in people with chronic kidney disease (CKD) undertaking dialysis. Methods:A systematic literature search was completed in December 2012 identifying randomized, controlled trials of exercise training studies in haemodialysis (HD) patients. A subsequent meta-analysis was conducted.Results: Twenty four studies were included, totalling 879 patients. Exercise training produced significant improvements in physical fitness: peak VO2 5.03 mlO2·kg-1·min-1 (95% CI 3.73, 6.33, p 0.0001), Knee extensor strength 2.99 kg (95% CI 0.46, 5.52, p = 0.02) and 6 minute walk distance 60.7 metres (95% CI 18.9, 103, p = 0.004). Significant increases in energy intake MD 238 Kcal·day-1 (95% CI 94, 383, p = 0.001), serum Interleukin-6 MD-0.58 pg·ml-1 (95% CI-1.01, -0.15, p = 0.008) and Creactive protein MD 0.92 mg/L-1 (95% CI 0.29, 1.56, p = 0.004), but not Albumin or BMI, were reported. Improved Beck Depression scores were reported MD-6.9 (95% CI-9.7,-4.1, p 0.00001). Dialysis adequacy was reduced MD-0.23 (95% CI -0.29, -0.17, p 0.00001), while serum potassium was higher MD 0.14 mmol·L-1 (95% CI 0.01, 0.27, p = 0.04). Moreover exercise training appeared safe, with no direct exercise-associated deaths in over 30,000 patient-hours. Conclusions: Our pooled analyses confirmed improvements in physical fitness following exercise training and suggested additional improvements in dialysis efficiency (kt/v), serum potassium, inflammation and depression in HD patients.

Effect of exercise training intensity on adipose tissue hormone sensitive lipase gene expression in obese women under weight loss

Background:Hormone sensitive lipase(HSL) is an enzyme that regulates adipose tissue lipolysis and plays an important role in chronic exerciseinduced changes in adipose tissue metabolism.The purpose of this study was to determine whether aerobic exercise intensity influences abdominal adipose tissue HSL gene expression in obese women under weight loss. Methods:Thirty women(body mass index(BMI) = 33.0±0.7 kg/m^2,age = 58±1 years) completed one of three 20-week interventions: caloric restriction alone(CR only,n = 8),CR plus moderate-intensity exercise(CR + moderate-intensity,45%—50%heart rate reserve(HRR). 3 day/week,n = 9),or CR plus vigorous-intensity exercise(CR + vigorous-intensity,70%—75%HRR,3 day/week,n = 13).Each group had a similar prescribed energy deficit comprised of underfeeding alone(2800 kcal/week for CR only) or underfeeding(2400 kcal/week) plus exercise(400 kcal/week).Body composition and maximal aerobic capacity(VO_2max) were measured,and subcutaneous abdominal adipose tissue samples were collected before and after the interventions.Adipose tissue HSL gene expression was measured by real time reversetranscriptase polymerase chain reaction. Results:All three interventions reduced body weight,fat mass,percent fat.and waist to a similar degree(all p < 0.01).In addition,all interventions did not change absolute VO_2 max,but increased relative VO_2 max(p < 0.05 to P < 0.01).Compared to pre-intervention.neither CR only nor CR + moderate-intensity changed adipose tissue HSL gene expression,but CR + vigorous-intensity significantly increased adipose tissue HSL gene expression(p < 0.01).The changes of HSL gene expression levels in the CR + vigorous-intensity group were significantly different from those in the CR only(p < 0.05) and CR + moderate-intensity(p < 0.01) groups.In the whole cohort,changes in adipose tissue HSL gene expression correlated positively to changes in absolute(r = 0.55,p < 0.01) and relative(r = 0.32,p = 0.09) VO_2 max. Conclusion:These results support a potential effect of aerobic exercise training intensity on hormone sensitive lipase pathway in adipose tissue metabolism in obese women under weight loss.

Concise review on the safety of exercise on symptoms of lymphedema

Lymphedema is an atypical accumulation of high-proteinfluid located just beneath the skin, which often occurs in the arm or leg. Exercising with lymphedema was traditionally considered to be unsafe. However, recent research indicates that exercise may be beneficial to individuals with lymphedema. Studies indicate that exercise can improve the range of motion and strength of the afflicted limb(s), as well as overall fitness and functional quality of life, and can be performed without exacerbating symptoms of lymphedema.

The BRICS Council for Exercise and Sport Science(BRICSCESS)--A new era has dawned

BRICS is the acronym for an international association of 5 major emerging national economies： Brazil, Russia, India, China, and South Africa.According to the World Economic Forum, the BRICS economies are the most competitive among all cotmtries and are distinguished by their significant regional and global influence. The health and wellness of the people within these countries is a primary agenda item of these governments for connecting their fast economic growth and the need to provide a better quality of life. As of 2015, BRICS countries represent 〉3.6 billion people or one-half of the world population. All 5 countries are members of the top 25 countries of the world by population and 4 of these cotmtries make the top 10 on this list.

The Influence of Exercise and Caffeine on Cognitive Function in College Students

Exercise has widely been shown to improve cognition, potentially by making individuals more receptive to sensory stimulation or inhibiting irrelevant information. Caffeine, one of the world’s most widely used stimulants, seems to have similar effects. It seems that both exercise and caffeine improve cognitive function separately, but little research has been done examining their combined effects. The purpose of this study was to examine the impact of caffeine and exercise, independently and combined, on cognitive function. 20 healthy college students completed the study. These participants were low caffeine consumers. Each participant came to the lab 5 times. During the first session, they completed a graded exercise test on a cycle ergometer to determine ventilatory threshold (VT). The following four sessions were test sessions involving supplementation and exercise. During these, each participant engaged in 30 minutes of cycling (at 90% VT) or 30 minutes of quiet reading after consuming either caffeine (at 4 mg/kg body weight) or a placebo. The Contingent Continuous Performance Task (CPT) and Wisconsin Card Sorting Task were used to measure cognitive function and were completed 5 minutes and 20 minutes after exercise or quiet reading. There were no significant differences found for any variables tested, for condition effect, time effect or condition*time interaction, except for a significant time effect on false alarms on the Contingent CPT (p = 0.017). This study may have been limited by multiple variables including the population, executive function measures, caffeine dosage, or exercise prescription. These findings point to the need for future research to understand the changes in cognition from exercise and caffeine in combination. Future research may include looking at exercise at different intensities, different dosages of caffeine, or looking at the long-term cognitive effects.

Taichi Softball as a Novel Chinese Health-Promoting Exercise for Physical Health: A Systematic Review and Meta-Analysis

Background: Taichi softball was voted as one of the most popular health-promoting exercises in the category of ball games, which is attributed to that Taichi softball is not only beneficial for lower extremity-related physical health (e.g., balance, leg strength, and flexibility), but can also develop manipulative skill and hand-eye coordination (eating, bathing, dressing, bathing required manipulative skills, grips movement and strength). However, the positive effects of Taichi softball on physical health have rarely been investigated. Therefore, the purpose of this systematic review was to evaluate the effect of Taichi softball on physical health. Methods: Five electronic databases were used to conduct literature searches. Two review authors independently extracted data in a standardized manner. The methodological quality of studies included was independently evaluated according to the Cochrane Collaboration’s for Assessing Risk of Bias from the Cochrane Handbook for Systematic Review Interventions. The standard mean difference (SMD) and 95% confidence interval (CI) using more conservative random effects model were calculated. Results: The sample size of 411 participants ranged from 32 to 150 in the RCTs, along with a wide age range from 18 to 75. The length of Taichi softball intervention peri-ods in the eligible studies ranged from 12 weeks to 12 months. The participants in the studies consisted of healthy college students, patients with Type 2 diabe-tes, and older adults from community centers. Six randomized controlled trials were used for the meta-analysis. The aggregated results are in favor of Taichi softball on improving physical health in participants with healthy status and Type 2 Diabetes Mellitus. The improvement on the primary components of the physical health consisted of handgrip strength (SMD, -0.6, 95% CI -0.84 to 0.36, p < 0.00001), trunk flexibility (SMD, -0.4, 95% CI -0.74 to -0.05, p = 0.03), static (SMD, -0.73, 95% CI -0.94 to -0.51, p < 0.00001) and dynamic balance (SMD, -0.68, 95% CI -1.2 to -0.17, p = 0.009). Conclusions: Taichi softball appears to be beneficial for improving physical health (hand strength, physical balance, flexibility, aerobic endurance, resting heart rate, diastolic and systolic pressures) among healthy adults and patients with Type 2 Diabetes. However, because of the low methodological quality of assessment, ill-designed experimental designs, and small study size, a definite conclusion of Taichi softball improving physical health can be confirmed along with high-quality studies with long follow-up.

Refinement of saliva microRNA biomarkers for sports-related concussion

Background:Recognizing sport-related concussion(SRC)is challenging and relies heavily on subjective symptom reports.An objective,biological marker could improve recognition and understanding of SRC.There is emerging evidence that salivary micro-ribonucleic acids(miRNAs)may serve as biomarkers of concussion;however,it remains unclear whether concussion-related miRNAs are impacted by exercise.We sought to determine whether40 miRNAs previously implicated in concussion pathophysiology were affected by participation in a variety of contact and non-contact sports.Our goal was to refine a miRNA-based tool capable of identifying athletes with SRC without the confounding effects of exercise.Methods:This case-control study harmonized data from concussed and non-concussed athletes recruited across 10 sites.Levels of salivary miRNAs within 455 samples from 314 individuals were measured with RNA sequencing.Within-subjects testing was used to identify and exclude miRNAs that changed with either(a)a single episode of exercise(166 samples from 83 individuals)or(b)season-long participation in contact sports(212 samples from 106 individuals).The miRNAs that were not impacted by exercise were interrogated for SRC diagnostic utility using logistic regression(172 samples from 75 concussed and 97 non-concussed individuals).Results:Two miRNAs(miR-532-5p and miR-182-5p)decreased(adjusted p<0.05)after a single episode of exercise,and 1 miRNA(miR-4510)increased only after contact sports participation.Twenty-three miRNAs changed at the end of a contact sports season.Two of these miRNAs(miR-26b-3p and miR-29c-3p)were associated(R>0.50;adjusted p<0.05)with the number of head impacts sustained in a single football practice.Among the 15 miRNAs not confounded by exercise or season-long contact sports participation,11 demonstrated a significant difference(adjusted p<0.05)between concussed and non-concussed participants,and 6 displayed moderate ability(area under curve>0.70)to identify concussion.A single ratio(miR-27a-5p/miR-30a-3p)displayed the highest accuracy(AUC=0.810,sensitivity=82.4%,specificity=73.3%)for differentiating concussed and non-concussed participants.Accuracy did not differ between participants with SRC and non-SRC(z=0.5,p=0.60).Conclusion:Salivary miRNA levels may accurately identify SRC when not confounded by exercise.Refinement of this approach in a large cohort of athletes could eventually lead to a non-invasive,sideline adjunct for SRC assessment.

Effect of Combined anti-Inflammatory and Nutritional Supplements on Recovery from Resistance Exercise

This study examined the effects of combined anti-inflammatories and specific nutrients on recovery from resistance exercises. Trained individuals （n = 14） performed three sets to failure at a 8-12 repetition maximum load for six resistance exercises, then repeated this workout after 24 h. Participants consumed a protein-carbohydrate shake （330 ml; 20 g protein; 45 g carbohydrate）, vitamin C （1000 mg）, vitamin E （400 I.U.） and ibuprofen （100 mg） immediately after the initial workout. Another dose of vitamin C and ibuprofen were respectively consumed 1 h or 30 min before the second workout. On another occasion （counterbalanced） a placebo of flavored water, two imitation vitamins （gummy candies）, and two replica ibuprofen （sugar pills） were consumed. A 10-cm visual analog scale （VAS） assessed pain, ratings of perceived exertion （RPE）, and ratings of perceived recovery （RPR）. Treatment enhanced performance-based recovery （repetitions after 24h） for the chest press （P 〈 0.010） and latissimus pull-down （P 〈 0.010）. Within-condition comparisons revealed performance decrements （P 〈 0.050） after 24 h for 83% of the exercises under placebo, compared to 50% of exercises under treatment. Treatment enhanced RPR （P = 0.038） compared to placebo, but had no significant effects on residual （P = 0.215） or exercise （P 〉 0.050） pain. RPE was lower under the treatment for the chest press （P = 0.016） and overall workout （P = 0.038） on Day 1, but similar among all exercises on Day 2 （P 〉 0.050）. This treatment may promote increases in performance without increasing pain or RPE.

Effect of an Acute Exercise Session on Body Composition Using Multi-Frequency Bioelectrical Impedance Analysis in Adults

The purpose of this investigation was to examine the effect of an acute bout of aerobic exercise （AE） and resistance exercise （RE） on body composition measured by multi-frequency bioelectrical impedance analysis （MBIA） in adults. Ninety-five recreationally active young adults （46 women and 49 men） reported for testing on three occasions. After an initial MBIA assessment, subjects performed 45 minutes of continuous AE, RE, or did nothing, which served as the control （CON）. During the AE trial, subjects performed an acute bout of treadmill exercise at 60%-75% of their age predicted maximal heart rate （APHRmax）. The RE trial consisted of an 8-exercise circuit consisting of; 3 sets of 10-12 repetitions at 65%-75% of their one-repetition max （1RM） for each exercise. During the CON trial, subjects sat quietly in the laboratory. Body composition was reassessed immediately following the exercise bouts for comparison. Mean percent body fat （%BF） decreased following the exercise bouts （AE = 0.7%, RE = 1.6%; P 〈 0.001） likely due to significant （P 〈 0.001） reductions in impedance （AE： 40Ω, 32Ω, and 29Ω; RE： 4592, 29Ω, and 28Ω） measured at 5, 50 and 500 kHz. Conversely, significant increases in %BF （0.7%, P 〈 0.05）, body mass （0.2 kg, P 〈 0.001）, and impedance at 5 and 50 kHz （15Ω and 16Ω; P 〈0.001） were observed following the CON trial. These findings support that MBIA assessments should be performed prior to exercise in order to prevent exercise-induced reductions in %BF values.

Effect of a combined inversion and plantarflexion surface on ankle kinematics and EMG activities in landing

Purpose： The purpose of this study was to examine the effects of landing kinematics and electromyographic （EMG） activities of medial gastrocnemius on a combined inversion and plantarflexion surface on the ankle （MG）, peroneus longus （PL）, and tibialis anterior （TA） muscles. Methods： Twelve recreational athletes performed five drop landings from an overhead bar of 30 cm height on to three surfaces： a flat surface, a 25° inversion surface, and a combined surface of 25° inversion and 25° plantarflexion. The kinematic variables and integrated EMG （IEMG） of the three muscles were assessed using a one-way repeated measures ANOVA and a 3 × 3 （surface × muscle） ANOVA, respectively （p 〈 0.05）. Results： The IEMG results showed a significant muscle by surface interaction. The flat surface induced higher TA activity than the two tilted surfaces. The inverted surface produced significantly higher inversion peak angle and velocity than the flat surface, but similar PL activity across the surfaces. The MG IEMG, ankle plantarflexion angle, and inversion range of motion were significantly higher for the combined surface compared to the inverted surface. Conclusion： These findings suggest that compared to the inversion surface, the combined plantarflexion and inversion surface seems to provide a more unstable surface condition for lateral ankle sprains during landing.

Exertional heat illness risk factors and physiological responses of youth football players

Objective:To determine which intrinsic and extrinsic exertional heat illness(EHI)risk factors exist in youth American football players and observe perceptual and physiological responses of players during events(games and practices).Methods:Cross-sectional cohort study observing 63 youth football players,varying in position.Independent variables were league(weightrestricted(WR,n=27)and age-restricted(AR,n=36))and event type.Dependent variables were anthropometrics,work-to-rest ratio,and wet bulb globe temperature.Descriptive variables included preparticipation examination and uniform configuration.A subset of 16 players participated in physiological variables(heart rate and gastrointestinal temperature).Data collection occurred on 7 AR and 8 WR nonconsecutive practices and the first 3 games of the season.Results:Mean values for anthropometric variables were higher(p<0.05)in the AR league than the WR league.Work time(χ^2(1,111)=4.232;p=0.039)and rest time(χ^2(1,111)=43.41;p<0.001)were significantly greater for games,but ratios were significantly higher for practices(χ^2(1,111)=40.62;p<0.001).The majority of events(77%)observed were in black and red flag wet bulb globe temperature risk categories.A total of 57%of the players had a preparticipation examination,and up to 82%of events observed were in full uniforms.Individual gastrointestinal temperature and heart rate responses ranged widely and no players reached critical thresholds.Conclusion:Extrinsic(disproportionate work ratios,environmental conditions)and intrinsic(higher body mass index)EHI risk factors exist in youth football.Certain risk factors may be influenced by event and league type.National youth football organizations need to create thorough guidelines that address EHI risk factors for local leagues to adopt.

Physical activity, aging, and health in China: Addressing public health needs in the presence of continued economic growth and urbanization

The significant increase in the number of older adults in China,coupled with continuing industrialization and urbanization,has profound social and economic ramifications,including the evolution of major challenges to public health,elder care services,policy-making,and the nation’s healthcare system.While the unprecedented changes in political and economic structures have obviously increased China’s productivity and revenues,what is less well understood is how they

Can physical activity eliminate the mortality risk associated with poor sleep?A 15-year follow-up of 341,248 MJ Cohort participants

Background:This study examined the joint associations of sleep patterns and physical activity(PA) with all-cause,cardiovascular disease(CVD),and cancer mortality.Methods:A total of 341,248 adults(mean age=39.7 years;men:48.3%) were included in the study,with a 15-year follow-up.Participants reported sleep duration and disturbances(difficulty falling asleep,easily awakened,or use of sleeping medication).PA was classified into 4 levels:<7.5,7.5-14.9,15.0-29.9,and>30.0 metabolic equivalent hours per week(MET-h/week).To understand the joint associations of sleep patterns and PA with mortality,Cox proportional hazard models were conducted,with exposure variables combining sleep duration/disturbances and PA.Results:Compared with the reference group(sleeping 6-8 h/day),individuals who slept>8 h/day had higher risk for all-cause mortality(hazard ratio(HR)=1.307,95% confidence interval(95%CI):1.248-1.369),CVD mortality(HR=1.298,95%CI:1.165-1.445),and cancer mortality(HR=1.128,95%CI:1.042-1.220).Short sleep duration was not associated with mortality risk.Increased risk of all-cause and CVD mortality was found in participants who had difficulty falling asleep(HR=1.120,95%CI:1.068-1.175;HR=1.163,95%CI:1.038-1.304,respectively),and used sleeping medication(HR=1.261,95%CI:1.159-1.372;HR=1.335,95%CI:1.102-1.618,respectively) compared with those who slept well.Long sleep duration and sleep disturbances were not associated with risk of all-cause and CVD mortality among individuals achieving a PA level of>15 MET-h/week,and in particular among those achieving> 30 MET-h/week.Conclusion:Long sleep duration,difficulty falling asleep,and use of sleeping medication were related to a higher risk of death.Being physically active at a moderate intensity for 25-65 min/day eliminated these detrimental associations.

Application of the neuromuscular fatigue threshold treadmill test to muscles of the quadriceps and hamstrings

Purpose:The purposes of the present study were:(1)to determine whether the physical working capacity at the fatigue threshold(PWCFT)model that has been used for estimating the onset of neuromuscular fatigue in the vastus lateralis(VL)during incremental treadmill running could also be applied to the vastus medialis(VM),biceps femoris(BF),and semitendinosus(ST)muscles;and(2)if applicable,to compare the running velocities associated with the PWCFT among these muscles.Methods:Eleven subjects(age 21.7±1.8 years)performed an incremental treadmill test to exhaustion with electromyographic signals recorded from the VL,VM,BF,and ST.Results:The results indicated there were no significant(p>0.05)mean differences in the running velocities associated with the PWCFT for the VL(14.4±2.0 km/h),VM(14.3±1.9 km/h),BF(13.8±1.8 km/h),and ST(14.7±2.3 km/h).In addition,there were significant inter-correlations(r=0.68-0.88)among running velocities associated with the PWCFT of each muscle.Individual results also indicated that 9 of the 11 subjects exhibited identical PWCFT values for at least 3 of the 4 muscles,but there were no uniform patterns for any intra-individual differences.Conclusion:The findings of the present study suggested that the PWCFT test is a viable method to identify neuromuscular fatigue in the quadriceps and hamstrings during incremental treadmill exercise and results in consistent PWCFT values among these muscles.

Applications and research trends of digital human models in the manufacturing industry

Virtual reality(VR)has been widely used in various manufacturing industries,and VR-based virtual manufacturing has received significant attention in the current intelligent manufacturing era.Digital human models(DHMs)are essential for virtual manufacturing applications.Additionally,researching new applications of DHMs has developed into an important academic research field.This paper aims to identify the applications and research trends of DHMs in the manufacturing industry and to provide a reference for the continued development of virtual manufacturing and DHMs.We selected a total of 49 related articles from a large number of articles published between 2014 and 2019.The applications of DHMs in the manufacturing industry are analyzed from different perspectives and various relevant technical limitations are discussed.The results indicate that the applications of DHMs differ significantly between different types of fields.The automotive industry is the main application field for DHMs,and assembly/maintenance simulations and evaluations are the main application types.Additionally,there are still some limitations in the establishment of virtual environments,motion control,and DHM evaluation that should be addressed.Finally,research trends in the application of DHMs are illustrated and discussed,including the planning and assessment of human-robot collaboration systems,the combination of DHMs and augmented reality,and improved motion planning for DHMs.In summary,the application of DHMs can improve the realism and effectiveness of virtual manufacturing,and DHMs will be more widely and deeply studied and applied in various manufacturing industries in the near future.

Automatic Detection of the Electrical Elicited Stapedius Reflex by Evaluation of Its Electromyographic Signals

This paper provides a first preliminary description of the dependencies between the stapedius muscle’s behavior and its neuronal activation with the adjustment of cochlear implants in mind. For that, stapedial electromyography (EMG) data are compared with EMG data which were derived from the quadriceps femoris muscle. The rationale behind is, that the stapedius muscle is classified as a striated skeletal muscle as the quadriceps femoris muscle is. Thus, the stapedius should expose a behavior which is similar to that of peripheral skeletal muscles. The stapedial reactions were provoked with contralateral acoustic stimulation and ipsilateral electrical stimulation, respectively. The data from the quadriceps femoris muscle were evoked voluntarily. The correlation of the derived data and their stimuli have shown the following main key points: 1) The stapedius muscle behaves like a regular skeletal muscle;2) The stapedius muscle exhibits an extended range in which the muscle’s force is linear to the stimulation;3) On both sides of the linear regime, the stapedius muscle exhibits a sigmoidal behavior.