Significant improvement after sensory tricks and trunk strength training for Parkinson’s disease with antecollis and camptocormia:A case report

BACKGROUND Patients with Parkinson's disease(PD)exhibit symptoms such as antecollis(AC)and camptocormia(CC).The pathology of these two conditions is unclear.Additionally,standard treatment methods have not been established.The article reports the case of a 65-year-old female patient with AC and CC who was treated with central and peripheral interventions to alleviate symptoms.CASE SUMMARY We present the case of a 65-year-old female PD patient with AC and CC.The course of the disease was 5 years.She was treated with rehabilitation strategies such as sensory tricks and trunk strength training.During the inpatient period,we compared and analyzed the patient's gait,rehabilitation assessment scale score,and angles of her abnormal trunk posture in the first week,the third week,and the fifth week.The patient's stride length increased,indicating that the patient's walking ability was improved.The Unified Parkinson's Disease Scale Part Three score and CC severity score decreased.Furthermore,the score of the other scale increased.In addition,the patient showed significant improvements in AC,upper CC,and lower CC angles.CONCLUSION This case study suggested that sensory tricks and trunk strength training are beneficial and safe for patients with AC and CC.

Analysis of Strength Training in the Training of Shot-Putters

The shot put is a sport that requires very high explosive power and precise technique.Strength training occupies the core position in the training of shot-putters,which can not only improve the throwing distance of athletes but also enhance their competitive state and prevent sports injuries.The purpose of this paper is to analyze the principles,classification,methods,and specific exercises of strength training in the training of shot-putters,in order to provide scientific training guidance for shot-putters.

The effects of 12 weeks of functional strength training on muscle strength,volume and activity upon exposure to elevated Gz forces in high-performance aircraft personnel

Background:Technological advancements in modern military and acrobatic jet planes have resulted in extraordinary psychophysiological loads being exerted upon flying personnel,including inducing neck and back pain.The purpose of this study was to examine the effects of 12 weeks of functional strength training on 1)the volume and strength of the neck and shoulder muscles and 2)muscular activity upon exposure to helmets of different masses and elevated Gz forces in a long-arm centrifuge in high-performance aircraft personnel.Methods:Eighteen participants underwent 12 weeks of functional strength training(n=12)or the control protocol(n=6)without additional strength training.Pre-and post-intervention tests included evaluations of isometric strength of the head extensor muscles,flexion,and lateral flexion and rotation,as well as magnetic resonance imaging(MRI)to measure the volume of the m.sternocleidomastoideus,m.trapezius,and deep neck muscles.Furthermore,during a long-arm centrifuge(+1.4 and+3Gz)protocol,the muscular activity levels of the m.sternocleidomastoideus,m.trapezius and m.erector spinae muscles were assessed without a flight helmet,with a helmet,and with a helmet and night vision goggles.Each participant’s perception of muscular strain was noted immediately after the long-arm centrifuge protocol.Results:The maximal isometric strength in all exercises and muscle volumes increased in the training group but not the control group(P<0.05).Relative muscle activity(%MVC)with a helmet decreased after the intervention in the training but not the control group(P=0.01).Relative muscle activity while wearing a helmet and night vision goggles was higher after intervention in the control group than in the training group(P<0.01).The perceived muscular strain of the neck muscles induced by the long-arm centrifuge did not differ between the groups.Conclusions:Twelve weeks of functional strength training improves the maximal isometric strength and volume of neck and shoulder muscles and leads to lower relative muscle activation upon exposure to elevated Gz forces in a long-arm centrifuge.

To Inquiry Technical Characteristics and Strength Training of Sports Dancing

The thesis analyzed the internal mechanism of technique formation of all kinds of dance action in sports dance, and its movement technical features mainly presented in five aspects： First, the control technology to maintain the correct posture; Second, fast and rhythmic bouncing technique of the body weight; Third, the parabolic shape and spiral motion technology of the body center of gravity; Four, strong wiggler technology of hip, waist and abdomen; Five, the rhythm techniques of chest, back, shoulders and arms. Aiming at the technical features for sports dance project, we can summarize the methods and means of training control force, speed strength, strength endurance and relative strength of sports dancing athletes and raise several important principles that should be followed.

A single session of strength training changed plasma levels of resistin,but not leptin in overweight and obese men

Obesity has a complex multifactorial etiology and is characterized by excessive accumulation of adipose tissue.Visceral adipose tissue has deleterious effects on health because it secretes large amounts of inflammatory cytokines.Nutritional calorie restriction associated with strength training may be useful in managing chronic systemic inflammation.This study aimed to evaluate the acute effect of a single strength-training session on plasma adipokine levels in sedentary,overweight,and obese young men.This study included twelve men(Age:[34.95±9.77]years;Height:[174.16±3.66]centimeter[cm];Weight:[97.83±12.87]kilogram(kg);body mass index[BMI]:[32.30±4.51]kg/m2),who performed a single strength training session.The strength training protocol consisted of 4 sets of 12 repetitions in the following six exercises,45°leg press,bench press,leg extension,machine row,leg curl,and shoulder press.Blood samples were collected before,immediately after,and 1-h subsequent after strength training.The plasma levels of resistin and leptin were measured.A significant decrease in resistin levels were found 1 h after the strength training session if compared to levels before the training session(pre-[before][2390±1199]picograms per milliliter[pg/mL]vs post-1 h[1-h subsequent][1523±798],6 pg/mL,p=0.0028).The plasma leptin levels did not differ at any time point.In conclusion,a very well controlled single session of strength training significantly decreased the plasma levels of resistin without altering the concentration of leptin in overweight and obese individuals.This effect,at least in part,supports the benefits of exercise by reducing the low grade inflammation and insulin resistance in obesity.

Reconfigurable Muscle Strength Training Robot with Multi-mode Training for 17 Joint Movements

Different from limb rehabilitation training,the purpose of muscle strength training is to reduce muscle atrophy and increase muscle strength and tolerance through strength training of limb muscles,and then improve the muscle strength level of muscles(groups),mainly for sports fitness and muscle strengthening groups and patients with muscle atrophy or muscle weakness caused by various diseases.In this paper,we developed a new reconfigurable muscle strength training robot,a bionic robot by imitating physicians to conduct muscle strength training for patients,which was developed with six training modes for 17 joint movements,that is,the shoulder flexion/extension,the shoulder internal/external rotation,the shoulder adduction/abduction,the elbow flexion/extension,the wrist supination/pronation,the wrist flexion/extension,the wrist radial/ulnar deviation,the hip flexion/extension,the hip internal/external rotation,the hip adduction/abduction,the knee flexion/extension,the ankle dorsiflexion/plantarflexion,the ankle adduction/abduction,the ankle inversion/eversion,the waist flexion/extension,the waist left/right rotation,and the waist left/right flexion.The reconfigurable mechanism was designed with fully electric adjuster and reconfigurable adaptors deployed on the driving unit,and six training modes were developed,namely,continuous passive motion,active exercise,passive–active exercise,isotonic exercise,isometric exercise and isokinetic exercise.Experiments with knee joint and elbow joint have shown that the developed reconfigurable muscle strength training robot can realize the multi-mode trainings for the 17 joint movements.

Effect of resistance training volume on body adiposity,metabolic risk,and inflammation in postmenopausal and older females:Systematic review and meta-analysis of randomized controlled trials

Purpose:This meta-analytical study aimed to explore the effects of resistance training(RT) volume on body adiposity,metabolic risk,and inflammation in postmenopausal and older females.Methods:A systematic search was performed for randomized controlled trials in PubMed,Scopus,Web of Science,and SciELO.Randomized controlled trials with postmenopausal and older females that compared RT effects on body adiposity,metabolic risk,and inflammation with a control group(CG) were included.Independent reviewers selected the studies,extracted the data,and performed the risk of bias and certainty of the evidence(Grading of Recommendations,Assessment,Development,and Evaluation(GRADE)) evaluations.Total body and abdominal adiposity,blood lipids,glucose,and C-reactive protein were included for meta-analysis.A random-effects model,standardized mean difference(Hedges’ g),and 95% confidence interval(95%CI) were used for meta-analysis.Results:Twenty randomized controlled trials(overall risk of bias:some concerns;GRADE:low to very low) with overweight/obese postmenopausal and older females were included.RT groups were divided into low-volume RT(LVRT,~44 sets/week) and high-volume RT(HVRT,~77 sets/week).Both RT groups presented improved body adiposity,metabolic risk,and inflammation when compared to CG.However,HVRT demonstrated higher effect sizes than LVRT for glucose(HVRT=-1.19;95%CI:-1.63 to-0.74;LVRT=-0.78;95%CI:-1.15 to-0.41) and C-reactive protein(HVRT=-1.00;95%CI:-1.32 to-0.67;LVRT=-0.34;95%CI,-0.63 to-0.04)) when compared to CG.Conclusion:Compared to CG,HVRT protocols elicit greater improvements in metabolic risk and inflammation outcomes than LVRT in overweight/obese postmenopausal and older females.

The training process： Planning for strength-power training in track and field. Part 2： Practical and applied aspects

Planning training programs for strength-power track and field athletes require an understanding of both training principles and training theory. The training principles are overload, variation, and specificity. Each of these principles must be incorporated into an appropriate system of training. Conceptually, periodization embraces training principles and offers advantages in planning, allowing for logical integration and manipulation of training variables such as exercise selection, intensification, and volume factors. The adaptation and progress of the athlete is to a large extent directly related to the ability of the coach/athlete to create and carry an efficient and efficacious training process. This ability includes： an understanding of how exercises affect physiological and performance adaptation （i.e., maximum force, rate of force development, power, etc.）, how to optimize transfer of training effect ensuring that training exercises have maximum potential for carryover to performance, and how to implement programs with variations at appropriate levels （macro, meso, and micro） such that fatigue management is enhanced and performance progress is optimized.

Different Resistance Exercise Interventions for Handgrip Strength in Apparently Healthy Adults: A Systematic Review

Background: Although handgrip strength is a biomarker for morbidity/mor-tality, there is lack of evidence on the effects of resistance training on handgrip strength in healthy adults of all ages. Objective: The aim of this systematic review was to assess the impact of resistance training on handgrip strength in healthy adults. Methods: Five databases/search engines were searched. Studies comparing different types of resistance exercise interventions versus a non-exercised control group on handgrip strength were included. The available data did not allow us to conduct the pre-planned meta-analyses;therefore, only descriptive statistics were performed to summarize the data. Results: Twenty studies (17 randomized and three non-randomized controlled trials) were included, most of which were conducted in older adults. Twelve studies reported no significant difference in the change in handgrip strength between the resistance training and control groups. Two studies showed increases in handgrip strength in the resistance training group compared with the control group. Other studies included results for multi-training groups or left/right hands and found increasing handgrip strength compared to controls, but only in one training group or one hand. Overall, the randomized and non-ran-domized clinical trials presented moderate risk of bias. Conclusions: Due to the lack of low risk-of-bias randomized controlled trials of young and middle-aged adults, different training protocols, and small sample sizes, the existing evidence appears insufficient to support resistance training for increasing handgrip strength in healthy adults. Future studies may seek to discern the optimal way to develop and employ resistance training to improve hand-grip strength.

Responsiveness of functional performance and muscle strength,power,and size to resistance training:A systematic review

There is a recent and growing interest in assessing differential responders to resistance training(RT)for diverse outcomes.Thus,the individual ability to respond to an intervention for a specific measurement,called responsiveness,remains to be better understood.Thus,the current study aimed to summarize the available information about the effects of RT on functional performance and muscle strength,power,and size in healthy adults,through the prevalence rate in different responsiveness classifications models.A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)and was registered at the International Prospective Register of Systematic Reviews(PROSPERO,CRD42021265378).PubMed/MEDLINE,Scopus,and Embase databases were systematically searched in October 2023.A total of 13 studies were included,totaling 921 subjects.Only two studies presented a low risk of bias.Regarding the effectiveness of RT,the prevalence rate for non-responders ranged from 0%to 44%for muscle strength,from 0%to 84%for muscle size,and from 0%to 42%for functional performance,while for muscle power,the only study found showed a responsiveness rate of 37%.In conclusion,a wide range of differential responders is described for all variables investigated.However,the evidence summarized in this systematic review suggested some caution while interpreting the findings,since the body of evidence found seems to be incipient,and widely heterogeneous in methodological and statistical aspects.

Prevalence and correlates of meeting the muscle-strengthening exercise recommendations among Chinese children and adolescents:Results from 2019 Physical Activity and Fitness in China—The Youth Study

Purpose This study aimed to describe the national prevalence of Chinese children and adolescents who met the World Health Organization muscle-strengthening exercise(MSE)recommendations and identify correlates of meeting the MSE recommendations.Methods Cross-sectional data from the 2019 Physical Activity and Fitness in China—The Youth Study,a nationally representative sample of Chinese children and adolescents(n=80,413;mean age=13.7 years;53.9%girls)and their parents,were analyzed.Children and adolescents who reported engaging≥3 days(up to 7 days)of MSE per week were classified as meeting the MSE recommendations.MSE,demographics,lifestyle behaviors(sport participation,moderate-to-vigorous physical activity,screen time,and sleep duration),exercise intention,peer and parental support,and parental MSE participation were assessed through self-reports.Logistic regression models were used to determine the correlates of meeting the MSE recommendations.The analyses were completed in 2020.Results Overall,39.3%of children and adolescents met the MSE recommendations.Girls,10th-12th graders,minorities,those from lower income households and those from families with lower parental education were less likely to meet the MSE recommendations.Children and adolescents who were proficient in≥2 sports were more likely to meet the MSE recommendations(adjusted odds ratio(aOR)=1.44,95%confidence interval(95%CI):1.26-1.65),as were those with more moderate-to-vigorous physical activity(aOR=1.57,95%CI:1.53-1.61).Additionally,children and adolescents with high exercise intention(aOR=1.60,95%CI:1.51-1.69),those whose parents met the adult MSE recommendations(aOR=1.46,95%CI:1.40-1.52),and those who received high peer(aOR=1.27,95%CI:1.20-1.34)and parental support(aOR=1.07,95%CI:1.04-1.12)were more likely to meet the MSE recommendations.Conclusion Less than two-fifths of Chinese children and adolescents met the World Health Organization MSE recommendations.The correlates identified in our study can help inform the development of school and community based strategies and policies to enhance participation in MSE and improve muscular fitness of all Chinese children and adolescents.

Effects of exercise training on diastolic and systolic dysfunction in patients with chronic heart failure

BACKGROUND Chronic heart failure(CHF)is a complex syndrome characterized by a progressive reduction of the left ventricular(LV)contractility,low exercise tolerance,and increased mortality and morbidity.Diastolic dysfunction(DD)of the LV,is a keystone in the pathophysiology of CHF and plays a major role in the progression of most cardiac diseases.Also,it is well estimated that exercise training induces several beneficial effects on patients with CHF.AIM To evaluate the impact of a cardiac rehabilitation program on the DD and LV ejection fraction(EF)in patients with CHF.METHODS Thirty-two stable patients with CHF(age:56±10 years,EF:32%±8%,88%men)participated in an exercise rehabilitation program.They were randomly assigned to aerobic exercise(AER)or combined aerobic and strength training(COM),based on age and peak oxygen uptake,as stratified randomization criteria.Before and after the program,they underwent a symptom-limited maximal cardiopulmonary exercise testing(CPET)and serial echocardiography evaluation to evaluate peak oxygen uptake(VO2peak),peak workload(Wpeak),DD grade,right ventricular systolic pressure(RVSP),and EF.RESULTS The whole cohort improved VO2peak,and Wpeak,as well as DD grade(P<0.05).Overall,9 patients(28.1%)improved DD grade,while 23(71.9%)remained at the same DD grade;this was a significant difference,considering DD grade at baseline(P<0.05).In addition,the whole cohort improved RVSP and EF(P<0.05).Not any between-group differences were observed in the variables assessed(P>0.05).CONCLUSION Exercise rehabilitation improves indices of diastolic and systolic dysfunction.Exercise protocol was not observed to affect outcomes.These results need to be further investigated in larger samples.

Effects of 12 weeks of back-squat training program on jump performances and bone markers in female students

Background:The training program promoted improvements of jump abilities throughout the musculoskeletal system including bone markers.The aim of this study is to examine both the acute and chronic response of bone markers to resistance training program.Methods:Ten female students(age:18±0.7 years,body mass:63±3.6 kg;height:164±5.2 cm)participated in this study.They were recruited for a back-squat training program for 12 weeks,two days/week.The full-back squat protocol consisted of 3–5 sets×3–8 repetitions at 45–55%one repetition maximum.Testing sessions included a 5 jump test(5JT),standing long jump(SLJ),drop jump(DJ),and vertical jump(VJ).Results:Substantial improvements in all testing jumps(5JT:∆10%;P=0.000;ES=1.72;SLJ:∆7%;P=0.000;ES=1.33;DJ:∆11%;P=0.000;ES=0.72;VJ:∆20%;P=0.000;ES=1.84)were found during post program in comparison to pre-program results.Moreover,a significant change(P≤0.05)of bone markers during post-exercise compared to pre-exercise either before or after the training program.Only collagen type I carboxy-terminal peptide(CICP)levels elevated after the training program(pre-exercise only)compared to former levels.Conclusion:12 weeks of back-squat training program resulted greater acute improvements of jump abilities with adaptation in all musculoskeletal system including bone formation.

Application of cross-migration theory in limb rehabilitation of stroke patients with hemiplegia

BACKGROUND Stroke is a common cause of neurological dysfunction,often resulting in hemiplegia.Thus,rehabilitation of limb function in stroke patients is an important step towards accelerating recovery and improving quality of life.AIM To investigate whether unilateral strength training in hemiplegic stroke patients could lead to cross-migration,an increase in bilateral muscle strength,and an improvement in lower limb motor function.METHODS We randomly divided 120 patients with hemiplegic stroke into two groups:Eexperimental and control groups,with 60 patients in each group.Both groups received routine rehabilitation treatment,while the experimental group additional-ly received ankle dorsiflexion resistance training on the healthy side for 6 wk.We measured the maximum voluntary contract(MVC),changes in surface electromyography(EMG),and the lower limb motor function using the simplified Fugl Meyer Motor Function Assessment Scale(FMA)before and within 1 wk after training.RESULTS The FMA score in the experimental group improved significantly compared to both their pre-training score and the control group's post-training score(P<0.05).The integrated EMG of the anterior tibialis muscle and pulmonary intestine muscle in the experimental group were significantly different after training than before(P<0.05).Furthermore,the MVC of the anterior tibialis muscle on both the healthy and affected sides and the MVC of the pulmonary intestine muscle on both sides showed significant improvement compared with before training and the control group(P<0.05).CONCLUSION Our findings suggest that ankle dorsiflexion resistance training on the healthy side in hemiplegic stroke patients can increase strength in the opposite tibialis anterior muscle and antagonist's muscle,indicating a cross-migration phenomenon of strength training.Furthermore,this type of training can also improve lower limb motor function,providing a new exercise method for improving early ankle dorsiflexion dysfunction.

Women and exercise in aging

Aging is associated with physiological declines, notably a decrease in bone mineral density （BMD） and lean body mass, with a concurrent increase in body fat and central adiposity. Interest in women and aging is of particular interest partly as a result of gender specific responses to aging, particularly as a result of menopause. It is possible that the onset of menopause may augment the physiological decline associated with aging and inactivity. More so, a higher incidence of metabolic syndrome （an accumulation of cardiovascular disease risk factors including obesity, low-density lipoprotein cholesterol, high blood pressure, and high fasting glucose） has been shown in middle-aged women during the postmenopausal period. This is due in part to the drastic changes in body composition, as previously discussed, but also a change in physical activity （PA） levels. Sarcopenia is an age related decrease in the cross-sectional area of skeletal muscle fibers that consequently leads to a decline in physical function, gait speed, balance, coordination, decreased BMD, and quality of life. PA plays an essential role in combating physiological decline associated with aging. Maintenance of adequate levels of PA can result in increased longevity and a reduced risk for metabolic disease along with other chronic diseases. The aim of this paper is to review relevant literature, examine current PA guidelines, and provide recom- mendations specific to women based on current research.

What is the most effective exercise protocol to improve cardiovascular fitness in overweight and obese subjects？

Background: Increased peak oxygen consumption(VO2 peak) can reduce cardiovascular risks associated with obesity. Our aim was to analyze the effect of a weight loss program on cardiovascular fitness in overweight(W) and obese(O) subjects.Methods: One hundred and sixty-seven subjects(77 males and 90 females), aged 18–50 years, performed a modified Bruce protocol before(pre)and after(post) a weight loss program of 24 weeks. This program combined physical training(strength, S; endurance, E; combined strength + endurance, SE; or physical activity recommendation, PA) 3 times per week, with a 25%–30% caloric restriction diet.Results: VO2 peak improved in overweight and obese males(pre and post values in L/min, respectively; W = 3.2 ± 0.6 vs. 3.7 ± 0.5, p < 0.001;O = 3.6 ± 0.6 vs. 3.8 ± 0.6, p = 0.013) as well as in overweight females(2.0 ± 0.3 vs. 2.3 ± 0.4, p < 0.001). VO2 peak in the first ventilatory threshold(VT1) increased for all 4 interventions in males(p < 0.05), except for S in the obese group(1.6 ± 0.2 vs. 1.7 ± 0.3, p = 0.141). In females, it increased in E(0.9 ± 0.2 vs. 1.4 ± 0.3, p < 0.001), SE(0.9 ± 0.2 vs. 1.2 ± 0.4, p = 0.003), and PA(0.9 ± 0.1 vs. 1.2 ± 0.2, p = 0.006) in overweight groups. Time-to-exhaustion improved in all subjects except for females in PA group(15.7 ± 0.3 min vs. 15.9 ± 0.3 min, p = 0.495).Conclusion: Our results suggest that all methods, including the recommendation of physical activity, can improve cardiovascular fitness in overweight subjects and obese males.

Chronic hemodynamic adaptations induced by resistance training with and without blood flow restriction in adults:A systematic review and meta-analysis

The purposes of this systematic review and meta-analysis of peer-reviewed literature were to examine the chronic effects of resistance training with blood flow restriction(RT-BFR)on hemodynamics,and to compare these adaptations to those induced by traditional resistance training(TRT)programs in adults(PROSPERO:Registry:CRD42022339510).A literature search was conducted across PubMed,Sports Discus,Scielo,and Web of Science databases.Two independent reviewers extracted study characteristics and blood pressure measures.Risk of bias(The Cochrane risk of bias tool for randomized controlled trials[RoB-2]),and the certainty of the evidence(Grading of Recommendations,Assessment,Development,and Evaluation[GRADE])were used.A total of eight studies met the inclusion criteria for systolic(SBP),diastolic(DBP),and mean arterial pressure(MAP).Regarding the comparison of RT-BFR vs.non-exercise,no significant differences favoring the exercise group were observed(p>0.05).However,when compared to TRT,RT-BFR elicited additional improvements on DBP(-3.35;95%CI-6.00 to-0.71;I^(2)=14%;z=-2.48,p=0.01),and on MAP(-3.96;95%CI-7.94 to 0.02;I^(2)=43%;z=-1.95,p=0.05).Results indicate that RT-BFR may elicit a decrease in DBP in comparison with TRT,but the lack of data addressing this topic makes any conclusion speculative.Future research on this topic is warranted.

Predicting muscular strength using demographics,skeletal dimensions,and body composition measures

The purpose of this study was to develop an equation to predict strength for seven common resistance training exercises using anthropometric and demographic measures.One-hundred forty-seven healthy adults(74 males,73 females,3512 yr,17410 cm,8819 kg)volunteered to participate.Body composition values(regional/total)and body dimensions were assessed using dual-energy x-ray absorptiometry(DEXA).Subjects underwent the following maximal strength assessments:Leg Press,Chest Press,Leg Curl,Lat Pulldown,Leg Extension,Tri-ceps Pushdown,and Biceps Curl.Multiple linear regression with stepwise removal was used to determine the best model to predict maximal strength for each exercise.Independent predictor variables identified(p<0.05)were height(cm);weight(kg);BMI;age;sex(0=F,1=M);regional lean masses(LM,kg);fat mass(FM,kg);fat free mass(FFM,kg);percent fat(%BF);arm,leg,and trunk lengths(AL,LL,TL;cm);and shoulder width(SW,cm).Analyses were performed with and without regional measures to accommodate scenarios where DEXA is un-available.All models presented were significant(p<0.05,R^(2)=0.68-0.83),with regional models producing the greatest accuracy.Results indicate that maximal strength for individual resistance exercises can be reasonably estimated in adults.

The Effects of Short-Term Resistance Training and Subsequent Detraining on Neuromuscular Function,Muscle Cross-Sectional Area,and Lean Mass

Purpose To examine and compare the effects of three days of dynamic constant external resistance(DCER)and isokinetic(ISOK)training and subsequent detraining on thigh muscle cross-sectional area(TMCSA)and thigh lean mass(TLM),ISOK peak torque(PT),DCER strength,isometric force,muscle activation,and percent voluntary activation(%VA).Methods Thirty-one apparently-healthy untrained men(mean±SD age=22.2±4.2 years;body mass=77.9±12.9 kg;height=173.9±5.4 cm)were randomly assigned to a DCER training group(n=11),ISOK training group(n=10)or control(CONT)group(n=10).Subjects visited the laboratory eight times.The first visit was a familiarization session,the second visit was a pre-training assessment,the subsequent three visits were for unilateral training of the quadriceps(if assigned to a training group),and the last three visits were the post-training assessments conducted at three days,one week,and two weeks after training ended.Results DCER strength increased from pre-to post-training assessment 1 in both limbs for the DCER group only,and remained elevated during post-training assessments 2 and 3(P<0.05).In addition,surface EMG for the biceps femoris was higher at post-training assessment 3 than at the pre-training assessment,and post-training assessments 1 and 2(P<0.05).No other training-related changes were found.Conclusion The primary finding of this study was that DCER strength of the trained and untrained limbs can be increased with three days of training.This has important implications for injury rehabilitation,where in the initial period post-injury strength gains on an injured limb can possibly be obtained with short-term contralateral resistance training.

Inter-Individual Rapid Force Improvements after Mixed Session and Traditional Periodization in Aging Adults:A Randomized Trial

Background Different periodization models have been widely used to improve maximum and rapid force in aging adults.However,it is unclear if some specific model can influence the remarkable heterogeneity of responsiveness to rapid torque improvements following resistance training.Aims Compare the effects of mixed session periodization(MSP)and traditional(TP)models on neuromuscular performance and individual responsiveness in aging adults.Methods Twenty-two aging men and women(64.6±5.2 years old;1.68±0.1 m;77.8±16.0 kg)completed the intervention period.They were assigned into MSP(n=11)or TP(n=11)resistance training for lower limbs.The outcome measures normalized dynamic leg press(5-RM:BM),absolute and normalized knee isometric peak torque(PT and PT:BM)and rate of torque development,and impulse were assessed at baseline and after three blocks of a 9-wk resistance training(3 sessions per week).Thigh leg lean mass was assessed by dual-energy x-ray absorptiometry at baseline and after the intervention.Results Similar increases were observed for 5-RM:BM(MSP:28.8%±13.5%and TP:26.4%±7.6%,P<0.001),PT(MSP:223.7±50.7 N·m and TP:189.9±58.6 N·m,P<0.001),but it was not observed for PT:BM(MSP:16.4%±16.5%and TP:4.7%±9.2%,P>0.05).Absolute and normalized RTD remained unchanged throughout intervention(P>0.05),but both groups improved impulse(MSP:22.1%±25.7%and TP:12.6%±45.2%,P<0.001).Only MSP responders(n=5)presented significant time effect for absolute RTD(P<0.05)and impulse(P<0.05).Conclusion Although both periodization protocols increased 5-RM:BM and PT,it was not interchangeable through improve-ments in RTD even adopting power training session.Furthermore,these results suggest a great inter-individual variability following different periodization models for aging people.