***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: STUDY DESIGN R and omized clinical trial , single-masked . OBJECTIVES To determine the effectiveness of using a modified neuromuscular electrical stimulation ( NMES ) training program as an adjunct treatment for improving quadriceps strength and physical function in rehabilitation following anterior cruciate ligament reconstruction ( ACLR ) . BACKGROUND NMES training for quadriceps strengthening has previously been shown to be an effective adjunct treatment following ACLR when performed against isometric resistance using a dynamometer with the knee positioned in flexion . We developed a modified version of published NMES protocol because some patients have difficulty tolerating the existing protocol and many clinics may not have instrumented dynamometers . There is a need to determine the effectiveness of this modified protocol . METHODS AND MEASURES Forty-three subjects who had undergone ACLR were r and omly assigned to either a group that received ( NMES group ) or did not receive ( comparison group ) the NMES treatment in conjunction with their rehabilitation . Group means for quadriceps strength and self-reported measures of knee function were compared after 12 and 16 weeks of rehabilitation . The proportion of subjects in each group achieving clinical criteria to initiate ambulation without crutches , treadmill running , and agility training at selected times during rehabilitation were also compared . RESULTS The NMES group demonstrated moderately greater quadriceps strength at 12 weeks ( effect size , 0.48 ) , and moderately higher levels of self-reported knee function at both 12 ( effect size , 0.72 ) and 16 ( effect size , 0.65 ) weeks of rehabilitation compared to the comparison group . A greater proportion of subjects in the NMES group achieved clinical criteria for advancing to agility training at 16 weeks . CONCLUSIONS The modified NMES quadriceps training protocol can be a useful adjunct to ACLR rehabilitation programs , but the treatment effect is smaller than what has been reported in previous studies Immediately after reconstruction of the anterior cruciate ligament , 110 patients were r and omly assigned to treatment with high-intensity neuromuscular electrical stimulation ( thirty-one patients ) , high-level volitional exercise ( thirty-four patients ) , low-intensity neuromuscular electrical stimulation ( twenty-five patients ) , or combined high and low-intensity neuromuscular electrical stimulation ( twenty patients ) . All treatment was performed isometrically with the knee in 65 degrees of flexion . All of the patients participated in an intensive program of closed-kinetic-chain exercise . After four weeks of treatment , the strength of the quadriceps femoris muscle and the kinematics of the knee during stance phase were measured . Quadriceps strength averaged 70 per cent or more of the strength on the uninvolved side in the two groups that were treated with high-intensity electrical stimulation ( either alone or combined with low-intensity electrical stimulation ) , 57 per cent in the group that was treated with high-level volitional exercise , and 51 per cent in the group that was treated with low-intensity electrical stimulation . The kinematics of the knee joint were directly and significantly ( p < 0.05 ) correlated with the strength of the quadriceps . There was a clinical ly and statistically significant ( p < 0.05 ) difference in the recovery of the quadriceps and the gait parameters according to the type of operation that had been performed : the patients who had had reconstruction of the anterior cruciate ligament with use of an autologous patellar-ligament graft did poorly compared with the other patients The aim of the present study is to compare the effect of electrical muscle stimulation combined with voluntary muscle contractions with a program only with voluntary muscle contractions during immobilization in casts after anterior cruciate ligament surgery . Twenty-three patients , 7 women and 16 men with a mean age of 28 yr , were r and omized into two groups : an experimental group ( 13 patients ) and a control group ( 10 patients ) . Post-operatively , the patients were immobilized for 3 wk in a full leg cast with the knee flexed at an angle of 20 degrees to 30 degrees and then in a knee cast for another 3 wk . All patients had a st and ard program with quadriceps muscle contractions . In addition , the experimental group received electrical stimulation of the quadriceps muscle 4 X 10 min , 3 times.wk-1 , at a frequency of 30 Hz . During each stimulation , the patients were requested to contract the quadriceps muscle voluntarily as well . When pre-operative measurements were compared with those at the end of the immobilization period ( 6 wk after the operation ) , a significantly larger reduction in the knee extension isometric muscle strength was found for the control group than for the experimental group . In comparisons of the data of the male subjects only , this difference was still seen to be significant . The cross-sectional area of the quadriceps muscle measured with computed tomography was significantly less reduced during the immobilization period in the experimental group than in the control group . ( ABSTRACT TRUNCATED AT 250 WORDS The purpose of this study was to compare the effects of two protocol s of electrical stimulation combined with voluntary contractions on the recovery of thigh muscles after  anterior cruciate ligament ( ACL ) surgery . Ten sportsmen with a mean age of 26 yrs were r and omly assigned into two groups : a 80 Hz stimulated group ( 5 patients ) and a 20 Hz stimulated group ( 5 patients ) . All patients received electrical stimulation of the quadriceps femoris , five days a week , for 12 weeks , and had a st and ard program of voluntary contractions . Muscle and fat volumes of the thigh were assessed using MRI before surgery and after 12 weeks of rehabilitation . Quadriceps and hamstring muscle strength were evaluated by isokinetic measurements . Twelve weeks after surgery , the quadriceps peak torque deficit in the operated limb with respect to the non operated limb at 180 degrees /s and 240 degrees /s was significantly ( p < 0.05 ) less in the 20 Hz group than in the 80 Hz group . This difference was not confirmed when comparing the pre-surgery quadriceps peak torque of the operated limb with the post-surgery one . Subcutaneous fat volume was increased for the two groups at the post-surgery test . This increase was significantly ( p < 0.05 ) greater for the 80 Hz group . Thigh muscle volume deficit was not significantly different between the two groups STUDY DESIGN Controlled laboratory study OBJECTIVES To determine the effects of pulse duration and stimulation duration on the evoked torque after controlling for the activated area by using magnetic resonance imaging ( MRI ) . BACKGROUND Neuromuscular electrical stimulation ( NMES ) is commonly used in the clinic without considering the physiological implication s of its parameters . METHODS AND MEASURES Seven able-bodied , college students ( mean + /- SD age , 28 + /- 4 years ) participated in this study . Two NMES protocol s were applied to the knee extensor muscle group in a r and om order . Protocol A applied 100-Hz , 450-microsecond pulses for 5 minutes in a 3-seconds-on 3-seconds-off duty cycle . Protocol B applied 60-Hz , 250-microsecond pulses for 5 minutes in a 10-seconds-on 20-seconds-off duty cycle . The amplitude of the current was similar in both protocol s. Torque , torque time integral , and normalized torque for the knee extensors were measured for both protocol s. MRI scans were taken prior to , and immediately after , each protocol to measure the cross-sectional area of the stimulated muscle . RESULTS The skeletal muscle cross-sectional areas activated after both protocol s were similar . The longer pulse duration in protocol A elicited 22 % greater torque output than that of protocol B ( P<.05 ) . After considering the activated area in both protocol s , the normalized torque with protocol A was 38 % greater than that with protocol B ( P<.05 ) . Torque time integral was 21 % greater with protocol A ( P = .029 ) . Protocol B failed to maintain torque at the start and the end of the 10-second activation . CONCLUSIONS Longer pulse duration , but not stimulation duration , result ed in a greater evoked and normalized torque compared to the shorter pulse duration , even after controlling for the activated muscular cross-sectional areas with both protocol s. LEVEL OF EVIDENCE Therapy , level 5 Neuromuscular electrical stimulation and voluntary muscle contraction are two exercise modes widely used in rehabilitation to strengthen skeletal muscle . Since there is no debate as to which mode is most effective , we compared electrical stimulation with voluntary contraction performed at matched intensities following reconstructive surgery of the anterior cruciate ligament . Forty men and women , aged 15 - 44 , were r and omly assigned to either an electrical stimulation or a voluntary contraction group .  None of the subjects had a previous history of neuromuscular injury . The subjects received treatment for 30 minutes a day , 5 days a week , for 4 weeks . Knee extension torque was monitored during treatment to try to match the absolute muscular tensions ( quantified as " activity " ) achieved during therapy . To match the activity of the subjects in the electrical stimulation group , who were treated at the highest stimulation intensity they could tolerate , the subjects in the voluntary contraction group were paced at progressively increasing intensities corresponding to 15 , 25 , 35 , and 45 % of the injured limb 's maximum voluntary torque during weeks 1 , 2 , 3 , and 4 , respectively . We found no significant difference between the groups in terms of maximum voluntary knee extension torque throughout the study period . In addition , 1 year after surgery , there was still no significant difference between groups with regard to knee extension torque ( p > 0.4 ) . These data suggest that neuromuscular electrical stimulation and voluntary muscle contraction treatments , when performed at the same intensity , are equally effective in strengthening skeletal muscle that has been weakened by surgical repair of the anterior cruciate ligament BACKGROUND AND PURPOSE Electrical stimulation has been shown to be effective in aiding the recovery of quadriceps femoris muscle force production after anterior cruciate ligament reconstruction . The actual dosage of stimulation ( training intensity ) has not been well described . The purpose of this investigation was to establish a dose-response curve for electrical stimulation regimens design ed to improve quadriceps femoris muscle recovery in patients after anterior cruciate ligament reconstruction . SUBJECTS AND METHODS We analyzed data from a sub sample ( n = 52 ) of patients receiving electrical stimulation ( N = 110 ) who were involved in a large , multicenter r and omized clinical trial investigating treatment strategies design ed to enhance quadriceps femoris muscle recovery . Fifty-two subjects ( 40 male , 12 female ) , with an age range of 15 to 43 years ( mean = 25 , SD = 7 ) , participated in 4 weeks of quadriceps femoris muscle training using either portable , battery-powered home stimulators or console stimulators design ed for clinical use . Training intensities were monitored by logging the electrically elicited knee extension torque and expressing this torque as a percentage of the uninvolved quadriceps femoris muscles ' maximal voluntary contraction force . After the 4 weeks of training , isometric muscle torque was assessed and a dose-response curve was generated . The relationship between training intensity and quadriceps femoris muscle torque was assessed with Pearson Product-Moment Correlation Coefficients . RESULTS A significant , linear correlation was found between training intensity and quadriceps femoris muscle torque . Subjects training with console , clinical generators trained at higher intensities than those training with portable , battery-operated generators ; such training result ed in higher quadriceps femoris muscle torque . CONCLUSION AND DISCUSSION These results support the use of high-intensity electrical stimulation and do not support the use of low-intensity or battery-powered stimulators when the goal is recovery of quadriceps femoris muscle force production in the early phases of rehabilitation after anterior cruciate ligament surgery . [ Snyder-Mackler L , Delitto A , Stralka SW , Bailey SL . Use of electrical stimulation to enhance recovery of quadriceps femoris muscle force production in patients following anterior cruciate ligament reconstruction This r and omized , double blind , controlled trial was design ed to determine the effectiveness of neuromuscular electrical stimulation of the knee extensor and flexor muscles in the prevention of muscular weakening after anterior cruciate ligament surgery .  Neuromuscular electrical stimulation treatment was given in addition to an early exercise therapy regimen and compared with an early exercise therapy regimen alone . Forty-nine patients after anterior cruciate ligament surgery were assigned r and omly either to a neuromuscular electrical stimulation and exercise group , a transcutaneous electrical nerve stimulation as analgesic and exercise group , or an exercise alone group as control . All groups received a st and ard regimen of rehabilitation after anterior cruciate ligament surgery . The neuromuscular electrical stimulation and transcutaneous electrical nerve stimulation group additionally received electrical stimulation during the first 6 weeks after surgery . Patients were measured for isometric and isokinetic torque in the knee extensor and flexor muscles after 6 , 12 , and 52 weeks . No statistical difference among groups was observed . It is concluded that neuromuscular electrical stimulation in combination with an early exercise therapy regimen is not significantly more effective in reducing weakening than an early exercise therapy regimen alone after anterior cruciate ligament surgery BACKGROUND AND PURPOSE Assessment of the quality of r and omized controlled trials ( RCTs ) is common practice in systematic review s. However , the reliability of data obtained with most quality assessment scales has not been established . This report describes 2 studies design ed to investigate the reliability of data obtained with the Physiotherapy Evidence Data 
    Output:
    
NMES combined with exercise may be more effective in improving quadriceps strength than exercise alone , whereas its effect on functional performance and patient-oriented outcomes is inconclusive .
Inconsistencies were noted in the NMES parameters and application of NMES .