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physical activities can preserve brain function and improve 
 blood flow and oxygen transfer2 as well as 
 slow the loss of hippocampal formational tissue in the aging brain .
because of its unique three - dimensional movement , horseback riding has been applied as a 
 physical therapy to stimulate movement to maintain balance3 .
one of its effects is to transfer movement to the pelvis , producing 
 an effect very similar to pelvic tilting4 . 

in addition , horseback riding exercises parts of the body that are not used by other 
 frequently performed exercises , including agonistic muscles , which are deep muscles that 
 contract and relax to maintain balance5 . psychological research on horseback
riding exercise indicates it decreases depression in 
 teenagers with emotional disorders6 as 
 well as improves teenagers self - esteem and self - control7 .
however , there is little information about horseback riding exercise as a physical therapy 
 and even less information about whether such exercise is effective for elderly people or 
 indeed how it may affect them .
therefore , this study investigated the effects of horseback 
 riding exercise on the background electroencephalogram ( eeg ) of elderly people who performed 
 horseback riding for 8 weeks .
all 
 participants or their guardians provided informed consent prior to participation . before the 
 start of the study , the purpose and methods were explained in detail to the participants . 

the participants were divided into 2 groups : a horseback riding exercise group and a control 
 group ( n = 10 each ) .
riding was performed for 15 minutes , 3 times per week 
 for 8 weeks .
the post - exercise tests were performed over a period of 8 weeks in the same 
 manner as pre - study tests .
we investigated the background eegs , specifically the relative alpha power index , in both 
 groups . for the exercise ,
we used jeju horses from the i rehabilitation center - affiliated 
 horse riding course ; these horses are normally used to provide riding experiences to 
 visitors and are therefore healthy , accustomed to their surrounding environment , well 
 trained , tame , and have stable strides .
all participants wore protective gear including 
 safety helmets , vests , and boots . at the beginning of the tests ,
the warm - up exercises were performed at a walking speed , which 
 was the slowest speed ( 110 m / min ) . for this study ,
the slowest walking speed was maintained 
 for the participants safety and comfort . in the exercise ,
an instructor led a horse by the 
 bridle while another assistant supported a participant by holding him or her by the leg 
 prevent them from falling from the horse and provide assistance as needed .
quantitative 
 electroencephalography can be used to diagnose neurological changes in the brain ; it 
 constitutes an electric signal due to an active change in the brain that can capture the 
 electrical flow between neurons through electrodes attached to the surface of the head8 .
we collected the eeg data using a 
 computerized polygraph ( polyg - i , laxtha inc .
, korea ) and telescan , which is a real - time 
 analysis program .
the eeg electrodes were attached to the surface of the head of the 
 participants as they were seated in a comfortable reclining chair . to reliably capture data , 
 the same researcher attached the electrodes and operated the testing instruments .
body and 
 head movements were controlled as much as possible , and the participant kept their eyes 
 closed for 3 minutes while resting in order to minimize the interruption of waves caused by 
 eye movement .
the eeg signals were analyzed for 60120 seconds , excluding the first and last 
 60 seconds when the test might have been influenced by external environments .
the background 
 eeg data were analyzed on the basis of a monopolar derivation from 8 points on the surface 
 of the head ; the 8 electrodes were attached to fp1 , fp2 , f3 , f4 , t3 , t4 , p3 , and p4 
 according to the international 1020 electrode system .
the saved data were transformed into 
 frequencies using a fast fourier transform , which expresses the quantitative relationship 
 between eeg frequencies and their intensity .
power spectrum analysis was subsequently 
 applied , and the band - to - band power was calculated .
the relative alpha power 
 ( 813  hz/450  hz ) , which emerges in a state of relaxation and rest , was subdivided into the 
 relative slow alpha power ( 811  hz/450  hz ) and the relative fast alpha power 
 ( 1113  hz/450  hz ) and analyzed .
the 
 pre- and post - intervention data were compared within each group and between groups by using 
 paired t - tests independent t - tests , respectively .
there were no significant differences in the general characteristics between groups ( p > 
 0.05 ) ( table 1table 1.general characteristics of participants ( n = 20)categoryhorseback riding(n=10)control(n=10)age ( years)69.5  3.269.7  3.5height ( cm)157.6  8.7158.5  6.8weight ( kg)58.8  7.959.2  6.7bmi
bmi : body mass index after the horseback riding program , the relative slower alpha power was analyzed ; it 
 appeared to be active in the t3 and p4 domains but was suppressed in the fp1 , fp2 , f3 , f4 , 
 t4 , and p3 domains ( table 2table 2.relative slow alpha power before and after the interventionpre - interventionpost - interventionhorseback ridingfp10.321  0.1470.308  0.177fp20.337  0.1500.326  0.148f30.339  0.1400.337  0.151f40.341  0.1590.319  0.164t30.288  0.1310.314  0.119t40.254  0.1540.212  0.096p30.369  0.1460.367  0.147p40.345  0.1970.351  0.166controlfp10.243  0.1370.288  0.177fp20.246  0.1350.277  0.176f30.251  0.1410.302  0.181f40.237  0.1530.279  0.201t30.216  0.1160.225  0.131t40.164  0.1410.210  0.155p30.291  0.1200.309  0.150p40.277  0.1510.325  0.180data are
moreover , after the horseback riding program , the relative faster alpha 
 power appeared to be active in all domains of the horseback riding exercise group but 
 suppressed in all domains of the control group ( table 
 3table 3.relative fast alpha power before and after the interventionpre - interventionpost - interventionhorseback ridingfp10.055  0.0330.058  0.033fp20.060  0.0340.061  0.034f30.059  0.0280.067  0.038f40.057  0.0250.062  0.039t30.060  0.0250.073  0.031*t40.054  0.0190.055  0.029p30.088  0.0720.098  0.059p40.078  0.0570.093  0.049*controlfp10.048  0.0260.045  0.028fp20.047  0.0300.045  0.031f30.058  0.0370.050  0.034f40.051  0.0420.046  0.035t30.059  0.0370.050  0.034t40.040  0.0240.039  0.018p30.064  0.0420.054  0.038*p40.054  0.0370.048  0.027data are mean  sd . *
. there was a significant difference between the horseback riding exercise and 
 control groups with respect to the f3 domain ( p < 0.05 ) ( table 4table 4.comparison of relative fast and slow alpha powerhorseback ridingcontrolrsafp10.013  0.1240.025  0.093fp20.020  0.1370.012  0.131f30.006  0.1330.037  0.114f40.020  0.1520.043  0.136t30.013  0.1120.018  0.075t40.040  0.1500.031  0.113p30.000  0.0920.018  0.122p40.026  0.1830.018  0.137rfafp10.000  0.0530.013  0.034fp20.000  0.0530.006  0.025f30.020  0.0410.019  0.040*f40.007  0.0590.000  0.036t30.007  0.0250.013  0.050t40.007  0.0450.006  0.044p30.007  0.0250.000  0.051p40.013  0.0350.000  0.051*p < 0.05 , rsa : relative slow alpha power , rfa : relative fast alpha power ) .
p < 0.05 * p < 0.05 , rsa : relative slow alpha power , rfa : relative fast alpha power
during acute graded maximal exercise , the alpha wave power is reportedly decreased in the 
 frontal and temporal lobes8 , 9 .
alpha wave power is an index of stable emotional status or 
 mental health ; in this regard , alpha wave power appears to be more closely associated with 
 mental stress than exercise intensity , which is physically recognized .
the present study 
 evaluated the changes in background eeg , specifically alpha wave power , which indicates 
 stability and relaxation10 , 11 .
the relative slow alpha power was analyzed before and after the horseback riding exercise 
 program ; the results show it increased equally in all brain wave domains in the control 
 group . in the horseback riding exercise group , the relative slow alpha power was active in 
 the t3 and p4 domains but suppressed in the fp1 , fp2 , f3 , f4 , t4 , and p3 domains .
after the 
 horseback riding exercise program , the relative fast alpha power was increased in all 
 domains of the horseback riding exercise group .
horseback riding exercise is considered to enhance 
 concentration and comfort by activating the brain waves in all domains .
the relative alpha 
 power by the motor learning process is reported to increase in the fz , cz , oz , c3 , c4 , t3 , 
 and t4 domains during learning through exercise imagination but is decreased in those 
 observing and performing behaviors12 , 13 .
after the learning process , the relative 
 alpha power differs significantly in participants who observe and actually perform behaviors 
 compared to those who perform exercise imagination in the pz , oz , c4 , t3 , and t4 domains , 
 indicating the brain activation level is higher during exercise learning through behavior 
 observation and actual performance than imagination exercise learning . in the present study , there were small differences in the attachment points of the 8 brain 
 wave channels , background eeg , and evoked eeg .
however , the results corroborate the notion 
 that learning through exercises helps increase the relative alpha power .
the main limitation 
 of this study is its lack of generalizability owing to the relatively small sample as well 
 as the fact that the daily life habits aside from the horseback riding exercise program were 
 known only through personal interviews .
therefore , individual life habits may have affected 
 the results . accordingly , further studies with more subjects and better evaluation methods 
 are required to confirm the results . moreover , further studies should investigate the 
 psychological , cognitive , and physical changes as a result of horseback riding .
finally , 
 comparative studies involving different age groups and patients suffering from differing 
 diseases and conditions should be performed .
[ purpose ] this study investigated the effect of horseback riding exercise on the 
 background electroencephalograms of elderly people who performed horseback riding for 8 
 weeks . 
 [ subjects ] twenty elderly people were divided into the horseback riding exercise 
 and control group ( n = 10 each ) . [ methods ] 
 the exercise was performed for 
 15 minutes , 3 times per week for 8 weeks . 
 electroencephalograms were analyzed . 
 
 post - exercise evaluation was performed after 8 weeks . 
 [ results ] after the horseback riding 
 exercise , the relative slower alpha power index was active in the t3 and p4 domains but 
 suppressed in the fp1 , fp2 , f3 , f4 , t4 , and p3 domains . 
 moreover , the relative faster 
 alpha power index was active in all domains of the horseback riding exercise group but was 
 suppressed in all domains of the control group . 
 there was a significant difference between 
 groups in the f3 domain . 
 [ conclusion ] the alpha power index increased significantly after 
 horseback riding exercise , suggesting the exercise improved background 
 electroencephalogram .