wiihabilitation is a new idea that came about after introduction of nintendo wii fit ( wii ) 
 for rehabilitation1 .
the nintendo wii is a 
 low - cost commercial gaming system that provides an attractive means of facilitating 
 exercise2 , 3 .
nintendo wii fit games encourage lower extremity movement , 
 challenge balance , and require the player to remain in a standing position during play . 

the wii has been used across 
 a variety of clinical specialties and may potentially be a useful in the rehabilitation of a 
 wide variety of conditions .
virtual reality - based training is a feasible and suitable 
 therapeutic intervention for dynamic balance in older adults5 , 6 .
the nintendo wii has been 
 used as a tool that provides a novel way to interact with games in order to promote physical 
 activities .
it directs the user s motor response to be either specific or global to train 
 motor abilities such as the range of motion of different limbs and whole body balance 
 training7 .
addition of the wii balance 
 training program to conventional exercise programs has been recommended to improve ankle 
 muscle strength in patients with functional ankle instability at a low cost8 .
it has also been reported that virtual 
 reality programs improve the static balance and dynamic balance of subjects with functional 
 ankle instability and can be used safely and efficiently by patients9 .
the foot and ankle make up complex anatomical structures that contribute significantly to 
 the function of the whole lower limb10 . 

ankle joint stability involves co - contractions of surrounding muscles , recognized as 
 agonist / antagonist activity , to facilitate reciprocal planar motion and protects and ensures 
 efficient function of the joint11 . 

the strength ratios between antagonistic muscle groups 
 have received considerable attention from clinicians during examinations and in monitoring 
 of rehabilitation progress13 .
also , they 
 are thought to be clinically relevant because co - activation of opposing muscles across a 
 joint may be important in maintaining dynamic joint stability14 .
the agonist / antagonist ratio was advocated to answer the dilemma 
 regarding a means of more objectively evaluating and comparing the muscle balance ( or 
 imbalance ) around a joint .
ratios for various muscle groups in both the upper and lower 
 extremities have been developed and have become an improved gold standard for 
 evaluation15 .
impaired foot function can give rise to many problems , such as strains on ligaments , poor 
 co - ordination , and impairment of the function of the muscles12 .
injuries to the ankle account for a large portion of the injuries 
 to the lower extremity .
it has been reported that 
 approximately 80% of ankle sprains lead to injury recurrence and instability16 .
ankle injury programs for prevention and 
 treatment have disadvantages relating to time and cost . repeated episodes of ankle sprain 
 often occur despite introduction of many rehabilitation programs .
further research clearly 
 is needed in this area in terms of both treatment and suggestions to reduce the rate of 
 ankle sprains17 . to the knowledge of the authors ,
there are no previous studies investigating the 
 effectiveness of nintendo wii fit training on muscle strength ratios of ankle muscles . 

additionally , many studies have investigated the inversion / eversion ratio , but patients 
 still suffer from ankle instability .
furthermore , it has been reported that the concentric 
 dorsiflexion / plantar flexion strength ratio was affected in chronic ankle instability ( cai ) 
 patients .
therefore , this study was conducted to investigate the effect of nintendo wii fit 
 training on the dorsiflexion / plantar flexion strength ratio as a new concept in the field of 
 prevention and rehabilitation of ankle injuries .
thirty- two healthy male college students from the faculty of physical therapy , cairo 
 university , participated in the study .
they were randomly assigned , using simple blind 
 randomization by using procedures such as coin tossing into two equal groups : an 
 experimental group ( group i ) and control group ( group ii ) ( table 1table 1.general characteristics of the participants in the experimental and control 
 groupsexperimental group ( n=16)control group ( n=16)age ( years)19.6  1.319.6  1.6weight ( kg)76.9  5.672.9  6.8height ( cm)173.2  5.5171.8  5.7 ) .
participants in group i performed the nintendo wii fit training program . 
 participants in group
ii were instructed to avoid participation in any strength training 
 programs until after the post - training testing .
participants were included in the study if they had good ankle muscle strength ( grade 
 four ) , normal flexibility of the ankle muscles , and a normal foot posture index . 

participants were excluded if they had a history of previous ankle surgery or ankle injury , 
 had a history of vestibular disorder , had previously participated in a strengthening or 
 athletic training program , or had pronated or supinated foot postures .
the foot posture 
 index total score reference values were as follows : normal = 0 to + 5 , pronated = + 6 to + 9 , 
 highly pronated 10 + , supinated = 1 to 4 , and highly supinated 5 to 12 .
the ethical committee of the faculty of physical therapy , cairo university , approved this 
 study .
all participants signed an informed consent form assuring that their participation 
 was voluntary . a brief orientation session about the protocol of the study , its aims , and 
 the tests to be performed was provided to each participant .
nintendo wii fit includes over 40 games covering strength training , yoga , aerobics , and 
 balance .
the wii training program in this study included an initial balance game ( table tilt 
 game ) for 2/3 of session s total duration followed by a muscle strength game ( standing 
 rowing squat game ) for 1/3 of the session s duration .
the sessions lasted up to 30 minutes 
 and were performed 3 times per week for 6 weeks .
the selected games target 
 agonist - antagonist muscle contraction specifically dorsiflexion and plantar flexion .
the 
 participant tries to move a ball into a hole in a tilting platform .
the platform tilted 
 according to weight redistribution on pressure sensors in a wii balance board ( wbb ) .
this 
 game allowed motion in antroposterior and mediolateral directions around the ankle joint . 

furthermore , it trained the participant to control the position of the center of gravity 
 ( cog ) during rapid changes of body movement .
the standing rowing squat game is a muscle conditioning game that requires the player to 
 perform squats by flexing the knees from a standing position until the flexed knee reach the 
 required level .
the required level was determined by cog movement displayed on the screen as 
 a red dot that must be kept in a blue area in the final position of each squats .
they increase joint compressive forces leading to increased joint 
 stability , increased muscle co - activation , and decreased joint shear forces18 .
they also dynamically recruit most of the 
 lower - body musculature , including the quadriceps femoris , hip extensors , hip adductors , hip 
 abductors , and triceps surae19 . a biodex system 3 isokinetic dynamometer ( biodex medical systems , shirley , ny , 
 usa ) was used for measuring the peak torques / body weight ( nm / kg ) of the ankle dorsiflexors 
 and plantar flexors to calculate the dorsiflexion / plantar flexion strength ratio .
each participant was 
 instructed to perform 5 sets of ankle plantar flexion and dorsiflexion through a 60 range 
 of motion ( rom ) ( from 40 plantar flexion to 20 dorsiflexion ) an angular velocity of 
 60/sec .
this is the best angular velocity for measuring muscle strength because it is easy , 
 safe , and a large number of motor units are recruited at low angular velocities20 .
the test procedures were performed twice , 
 once before and once after the wii training program in the experimental group and at the 
 beginning of the study and then after 6 weeks in the control group .
statistical analysis was performed with ibm spss statistics for windows version 20 ( ibm 
 corp . ,
armonk , ny , usa ) . 2  2 mixed design analysis of variance ( anova ) was conducted to 
 compare the isokinetic ankle dorsiflexion / plantar flexion strength ratio between the 
 experimental and control groups before and after the training .
initially and prior to final 
 analysis , data were screened for normality assumption using shapiro - wilks normality test . 

the mean values of the ankle dorsiflexion / plantar flexion strength ratio decreased 
 significantly ( f=7.41 , p=0.01 ) between before and after the training .
the mean values of the 
 ankle dorsiflexion / plantar flexion strength ratio were significantly decreased in the 
 experimental group after the training when compared with before the training .
however , there 
 was no significant difference between before and after the training period in the control 
 group ( table 2table 2.comparison of the mean changes in the ankle dorsiflexion / plantar flexion strength 
 ratio between the experimental and control groupsexperimental groupcontrol groupbeforeafterbeforeafterankle dorsiflexion / plantarflexion strength ratio 
 ( % ) 78.8  31.757  18.2 * 66.1  31.758.5  28.6*significant difference within group ( p<0.05 ) ) . * significant difference within group ( p<0.05 )
nintendo wii fit was released just over six years ago as a mean of improving basic fitness 
 and overall well - being .
it has been adopted by a number of practitioners to assist in the 
 treatment of various impairments .
however , much work remained to be done to identify which 
 type of participants would benefit from it , which system features are critical , and what 
 types of training routine levels would work best . in addition , there have been few studies 
 with randomized controlled designs that have investigated its effect on agonist / antagonistic 
 muscle ratios and how this kind of training should be carried out .
the results of the current study revealed a significant decrease in the ankle 
 dorsiflexion / plantar flexion strength ratio after the training compared with before the 
 training in the experimental group .
meanwhile , there was no significant difference between 
 before and after the training period in the control group .
this might indicate an effect 
 caused by the wii training program as the control group did not receive training . in the present study
, the decreased strength ratio can be attributed more to the increased 
 peak torque of the plantar flexors than the dorsiflexors , as the mean sd values for the 
 peak torque of the plantar flexors increased from 54.1  22.85 nm / kg before the training to 
 96.1  30.83 nm / kg after the training , an improvement of 42% . on the other hand , the mean  

nm / kg before the 
 training to 55.73  15.37 nm / kg after the training , an improvement of 17.27% .
this may be explained by 
 wii training acting as a form of neuromuscular training with feedback .
neuromuscular 
 training is defined as a multi - intervention program with a combination of balance and 
 strength training21 , 22 .
it improves mechanical leg muscle strength due to training - induced 
 gains in neuromuscular function including strength gains23 , 24 .
previous literature reported that lower extremity functional retraining depends not only on 
 lower - limb mobility and bilateral coordination , but also requires other motor skills , such 
 as balance control21 .
therefore , better controlled movement of joint results from 
 increased muscle strength4 . for this 
 reason ,
combined strength and balance training should be incorporated into lower limb 
 rehabilitation to augment the potential outcomes of training and rapid recovery .
moreover , the squat is considered one of the best exercises for improving quality of life 
 because of its ability to recruit multiple muscle groups in a single maneuver26 .
the 
 squat has biomechanical and neuromuscular similarities to a wide range of athletic movements 
 and thus is included as a core exercise in many sports routines which designed to enhance 
 athletic performance28 .
the feedback provided in wii training is very important for user motivation and positive 
 reinforcement2 .
this feedback in the 
 form of either knowledge concerning performance or knowledge concerning results , has been 
 found to enhance motor skill learning29 . 

motion about the ankle joint is controlled by combined actions of at least one pair of 
 opposing muscles ( the tibialis anterior and gastrocnemius ) .
therefore , the calf muscles are 
 important in maintaining an erect posture and have a major role in controlling the ankle 
 joint , which is often one of the first joints to help the body restore its equilibrium after 
 perturbation31 .
pronator weakness , evertor weakness , and calf dysfunction are all terms used to describe 
 the cause of chronic ankle instability cai15 .
cai patients have higher ankle dorsiflexion / plantar flexion 
 strength ratio ) resulting from lower plantar flexors strength32 . in the same context ,
findings of the current study showed a 
 decreased ankle dorsiflexion / plantar flexion strength ratio .
for this reason , cai patients 
 may benefit from the wii training principles , as the training program combines the benefits 
 of balance training , closed kinetic chain exercise , and feedback effects .
neuromuscular training programs are implemented with the aim of optimizing performance , 
 preventing injury , or providing rehabilitation in functional ankle instability patients33 .
mcguine and keene34 showed the effectiveness of neuromuscular training in 
 reducing sport - related injury risk .
any neuromuscular 
 training program should incorporates a variety of physical activities that supports 
 increasing strength and balance36 .
this study was limited to healthy male adults who had no ankle deficits , and it only lasted 
 for six weeks .
the selected games for the training protocol were ( rowing squats and table 
 tilt ) activities from nintendo wii fit . based on the findings of the current study ,
wiihabilitation is recommended as a preventive 
 measure and treatment modality for ankle instability in sedentary individuals and athletes . 

thus , the field of physical therapy may improve the rehabilitation protocol for ankle 
 injuries by introducing wiihabilitation as a novel method for rehabilitation .
further studies should be carried with wider age categories , as this would be valuable for 
 determining the responses of different age categories to wii training .
it is recommended to explore the 
 correlation between the effect of wii training and the results of functional performance 
 tests .
additionally , extending the training period beyond two months may be advisable to 
 elicit more significant effects .
 [ purpose ] this study was conducted to investigate the effect of wiihabilitation on the 
 ankle dorsiflexion / plantar flexion strength ratio in adults . [ subjects and methods ] 
 thirty - two healthy male volunteers were randomly assigned to two equal groups 
 ( experimental and control ) . 
 participants in the experimental group received a 
 wiihabilitation training program for six weeks . 
 data were collected using a biodex system 
 3 isokinetic dynamometer . 
 peak torques of the dorsiflexors and plantar flexors were 
 measured at an angular velocity of 60/sec which in turn were used to derive the ankle 
 dorsiflexion / plantar flexion strength ratio . 
 [ results ] the mean values of the ankle 
 dorsiflexion / plantar flexion strength ratio decreased significantly between before and 
 after the training in the experimental group , meanwhile there was no significant 
 difference between before and after the training period in the control group . 
 
 [ conclusion ] wiihabilitation has an impact on the ankle dorsiflexion / plantar flexion 
 strength ratio , so it can be considered an effective training tool in terms of the ankle 
 strength ratio . 
 thus , it could be recommended for both prevention and rehabilitation of 
 ankle instability patients . 