ankle pumping exercises utilize a calf muscle pump function to pump blood to the heart by 
 muscle contraction . ankle pumping exercises are often used for the relief of edema3 and the prevention of deep vein thrombosis 
 ( dvt)1 , 2 , which are associated with prolonged bed rest . a 2009 guideline for 
 the diagnosis , treatment , and prevention of pulmonary thromboembolism and deep vein however , there has been much debate about 
 the most effective methods5 and modes of 
 ankle pumping exercises6 . studies have discussed the optimal velocity of muscle contractions7 and the frequency of performing ankle pumping exercises8 , but the ankle positions and exercise 
 intervals have not been evaluated in detail9 . therefore , evaluation of the most effective methods and mode of 
 ankle pumping exercises can contribute to standardizing the use of ankle pumping 
 exercises . the aim of this study was to identify the most effective methods and modes of ankle pumping 
 exercises . changes of blood flow velocity in the common femoral vein during ankle pumping 
 exercises with different ankle positions and exercise intervals were compared . the study subjects were 10 men without a history of cardio - vascular diseases and no 
 contraindications for exercise testing and training based on a scientific statement from the 
 american heart association10 . one experimenter ( y.f . ) measured the blood flow velocity in all of these experiments . we 
 measured time - averaged maximum flow velocity ( tamv ) and peak systolic velocity ( psv ) in the 
 left common femoral vein using a pulse doppler method with a diagnostic ultrasound system 
 ( acuson p300 , siemens , germany ) . tamv is the averaged blood flow velocity per unit time in 
 the left common femoral vein and psv is the maximum blood flow velocity in the left common 
 femoral vein during exercise . the increased amount of blood flow velocity was determined by subtracting tamv during rest 
 from psv during exercises . the subject s heart rate and electrocardiogram were monitored 
 continuously during the muscle pumping exercise . immediately after each muscle pumping 
 exercise , the subjects rated their local muscle fatigue using a modified borg scale . systolic blood pressure ( sbp ) and diastolic blood pressure ( dbp ) were also measured before 
 and immediately after the pumping exercises using an automatic blood pressure monitor 
 ( suntech tango+ , suntech medical , usa ) . subjects assumed three different exercise positions : supine ( supine position ) , supine with 
 their legs up after raising the bed to an 18-degree angle ( leg - up position ) , and supine with 
 their head up after raising the bed to a 30-degree angle ( head - up position ) ( fig . after the rest , we measured tamv in the left common 
 femoral vein for 20 sec . the ankle pumping exercises consisted of simple repetitions of 
 dorsiflexion for 1 sec and plantarflexion for 1 sec with three different exercise intervals : 
 repeated dorsiflexion and plantarflexion with no rest ( no - rest exercise ) , repeated 
 dorsiflexion and plantarflexion with a 2-sec rest period ( 2-sec rest exercise ) , and repeated 
 dorsiflexion and plantarflexion with a 4-sec rest period ( 4-sec rest exercise ) . in total , 
 the subjects performed nine ankle pumping exercises with different positions and exercise 
 intervals . experimental protocol one - way analysis of variance ( anova ) was used to compare tamv between the three resting 
 positions . two - way anova for repeated measures was used to compare psv and the increased 
 amount of blood flow velocity . all analyses were performed using spss statistics ver.17.0 ( ibm , tokyo , japan ) , and 
 statistical significance was accepted at an alpha level of 0.05 . this study was approved by the human ethics review of tokyo university of technology 
 ( approval number ; e14hs-026 ) . during a rest period , tamv of the leg - up position ( 24.4  3.1  cm / sec ) was significantly 
 higher than that of the supine ( 19.9  1.9  cm / sec ) and head - up positions ( 15.0  1.2  cm / sec ) 
 ( leg up vs. supine , p < 0.05 ; leg up vs. head up , p < 0.05 ) . tamv showed no 
 significant difference between the supine position and head - up position ( table 1table 1.time averaged maximum flow velocity in the common femoral vein in three different 
 positions during rest ) . for the no - rest exercise , psv of the leg - up position was significantly lower 
 than that of the supine position ( leg up 61.0  15.7 vs. supine 73.7  13.5 , p < 0.01 ) . for the 2-sec rest exercise , psv of the leg - up position was significantly lower than that of 
 the head - up position ( leg up 62.5  15.6 vs. head up 77.0  19.8 , p the leg - up position was significantly lower than those of the supine 
 and head - up positions ( leg up 61.5  12.1 vs. supine 77.9  10.1 , head up 86.9  9.1 , p < 
 0.01 ) . overall , the psv of the leg - up position was the lowest in all exercise intervals 
 ( table 2table 2.peak systolic velocity and increased amount of blood flow velocity in the common 
 femoral vein in three different positions during three different exercise 
 intervals ) . for the no - rest exercise , the increased amount of blood flow velocity in the leg - up 
 position was significantly lower than that in the head - up position ( leg up 22.8  9.1 vs. 
 head up 42.7  12.7 , p < 0.01 ) and the increased amount of blood flow velocity in the 
 leg - up position was lower than that in the supine position ( leg up 22.8  9.1 vs. supine 
 35.2  12.4 , p < 0.05 ) . for the 2-sec rest exercise , the increased amount of blood flow 
 velocity in the leg - up position was lower than that in the head - up position ( leg up 28.3  
 11.8 vs. head up 50.7  19.0 , p < 0.01 ) and the increased amount of blood flow velocity 
 in the leg - up position was lower than that in the supine position ( leg up 28.3  11.8 vs. 
 supine 40.6  15.1 , p < 0.05 ) . for the 4-sec rest exercise , the increased amount of blood 
 flow velocity in the leg - up position was significantly lower than that in the head - up 
 position ( leg up 28.3  10.3 vs. head up 57.1  13.5 , p < 0.01 ) and the increased amount 
 of blood flow velocity in the leg - up position was significantly lower than that in the 
 supine position ( leg up 28.3  10.3 vs. supine 45.2  9.0 , p < 0.01 ) . although none of 
 the differences between the exercise intervals reached significance , there was a tendency 
 that the 4-sec rest exercise increased the amount of blood flow velocity the most ( table 2 ) . tamv of the leg - up position during the resting period was the highest among the three 
 positions . generally , the venous blood pressure is lower than the arterial pressure , and the 
 venous blood pressure is affected by gravity11 , that is , blood flows downhill . the blood flow velocity is 
 calculated by dividing the blood volume ( cm / sec ) by the blood vessel dimension 
 ( cm ) . therefore , the blood flow velocity positively correlates with the blood 
 volume , and the vessel diameter negatively correlates with the blood flow velocity12 . we thought that the blood flow velocity in the common femoral vein in the leg - up position 
 was the highest because the blood flow volume from the lower limbs to the heart increased by 
 raising the legs . there was no significant difference between tamv for the supine or head - up 
 position during rest but the tamv of the head - up position was found to be the lowest of all 
 three positions . generally , blood pooling in the lower limbs can not flow back to the heart 
 by only heart pumping . in order to get blood back out of the legs the calf muscle pump is 
 essential13 . in the head - up position 
 during a rest , the blood flow volume to lower limbs increased due to gravity , and the muscle 
 pump was not working . therefore , 
 the tamv of the head - up position during rest was lower than any other position . conversely , the psv of the leg - up position was lower than that of the supine and head - up 
 position . this is because the blood pooling in the lower limbs was reduced by raising the 
 legs . when blood pools in the lower limbs it is essential to send blood out of the lower 
 limbs to the heart using the muscle pump . the blood volume in the lower limb in the leg - up 
 position could have been reduced by gravity even before doing muscle pumping exercises . therefore , the amount of blood volume output by the muscle pumping exercises was small and 
 the blood flow velocity was not increased very much . the increased amount of blood flow velocity in the leg - up position was significantly 
 smaller than that of the supine and head - up positions . by raising the legs , venous return 
 increases because of gravity and it is inferred that raising the legs might have prevented 
 pooling of blood in the lower limbs . we thought that the increased amount of blood flow 
 velocity in the leg - up position was the lowest of the three positions due to these 
 reasons . the short rest time might lead to little pooling of blood in the lower limbs . if the blood 
 volume is related to the increased amount of blood flow velocity , it is assumed that the 
 differences in rest time may cause the changes in the increased amount of blood flow 
 velocity . in this study , there were no significant differences among the three rest 
 exercises , but there was a tendency that the increased amount of blood flow velocity 
 increased with increasing rest time . this suggests that the amount of pooling blood in the 
 lower limb might be important for increasing blood flow . ankle positions and exercise 
 intervals must be taken into account for performing effective ankle pumping exercises . aging causes vascular degeneration and 
 reduced vascular elasticity that can lead to reduced venous return so it takes a longer time 
 for older people to pool blood in the lower limb . this can affect the results and indicates 
 that a study including older people should be done in the future .
[ purpose ] the aim of this study was to identify the most effective method of performing 
 ankle pumping exercises . [ subjects and methods ] the study subjects were 10 men . we 
 measured time - averaged maximum flow velocity and peak systolic velocity in the common 
 femoral vein using a pulse doppler method with a diagnostic ultrasound system during nine 
 ankle pumping exercises ( three different ankle positions and three exercise intervals ) . 
 changes of blood flow velocity during ankle pumping exercises with different ankle 
 positions and exercise intervals were compared . 
 [ result ] peak systolic velocity of the 
 leg - up position showed significantly lower values than those of the supine and head - up 
 positions . 
 for all exercise intervals , the increased amount of blood flow velocity in the 
 leg - up position was significantly lower than that in the head - up and supine positions . 
 [ conclusion ] ankle positions and exercise intervals must be considered when performing 
 effective ankle pumping exercises .