the first and second leading causes of death worldwide are ischemic heart disease and 
 cerebrovascular disease , respectively , according to a report projecting mortality data from 
 1990 to 20201 . it 
 develops due to hypertension , inflammation , ages ( advanced glycation end products ) , and 
 changes in heart rate3 , 4 . according to the world health organization , 51% of stroke 
 ( cerebrovascular disease ) and 45% of ischemic heart disease deaths are attributable to high 
 blood pressure5 moreover , high resting 
 heart rate has been reported to increase cardiovascular events6 and cause persistent hypertension7 . thus , prevention of hypertension and high resting heart rate could 
 lead to a decrease in the number of cardiovascular events . hernelati et 
 al.8 reported an inverse correlation 
 between the amount of slow twitch muscle fiber and hypertension . lower capillary density has 
 been associated with higher resting heart rate and mean blood pressure as well9 . the capillary density of slow twitch muscle 
 fiber is higher than that of fast twitch fiber10 . moreover , sedentary lifestyle has been linked to a high household 
 resting heart rate11 . a positive 
 correlation has been reported between the amount of slow twitch fiber and physical 
 activity12 . however , measurement of the 
 amount of slow twitch fiber and capillary density using muscle biopsy is inconvenient and 
 expensive . although this information could be useful for preventing cardiovascular events , 
 these measurements are difficult to perform in clinical settings . the triceps surae forms a major part of the muscle of the posterior leg13 , and is commonly known as the calf muscle . moreover , a positive correlation has been 
 reported between calf circumference and appendicular muscle mass14 , and the triceps surae muscle encompasses the soleus , in 
 which the proportion of slow twitch fiber is almost 90%13 , 15 . thus , measurement of 
 the calf circumference may provide valuable information regarding susceptibility toward 
 adverse cardiovascular events . in the present pilot study , we tested the hypothesis that 
 calf circumference is related to resting blood pressure and resting pulse rate . the subjects were healthy elderly women ( n = 19 ) living in the community with ages ranging 
 from 6184  years . women were excluded if they had edema of the lower leg , or had a 
 previous history of lower leg fracture . we have often had difficulty in measuring maximum calf circumference due to atrophy and 
 other factors . setting the distance from the inferior pole of the caput fibulae to the 
 center of the lateral malleolus as the length of the lower limb , maximum calf circumference 
 is the point 26% below the inferior pole of the caput fibulae in young people16 . thus , maximum calf circumference was 
 measured at a point 26% below the inferior pole of the caput fibulae . we measured the length 
 from the inferior pole of the caput fibulae to the center of the lateral malleolus using a 
 tape measure and calculated 26% of the length . two investigators measured the calf 
 circumference from the left side of the subjects using a tape measure . the measurements were 
 recorded with the subjects in the sitting position with the sole of the foot touching the 
 floor . the hip , knees , and ankles were flexed at 90 , 90 , and 0 , respectively . the 
 interclass correlation coefficient ( 1,1 ) systolic and diastolic pressures were measured using an automatic hemodynamometer ( hem-907 , 
 omron health care , kyoto , japan ) after subjects had sat for a 5-min rest period . blood 
 pressure was automatically measured twice , and the average values of the systolic and 
 diastolic pressures were recorded . the measurements were recorded from the left arm at the height of the 
 heart . pulse rate was measured at the left radial artery by palpating for 1  min . blood 
 pressure and pulse rate were measured between 9:00 and 11:00  h by two investigators . the associations between blood pressure , pulse rate , and calf circumference were evaluated 
 using pearson s product - moment correlation coefficient , and p < 0.05 was considered 
 statistically significant . sd , standard deviation pearson s product - moment correlation coefficient * : p<0.05 , n=19 the characteristics of the study subjects are presented in table 1 . the interclass correlation coefficient ( 1,1 ) of calf 
 circumference pearson s 
 product - moment correlation coefficient revealed there was no correlation between calf 
 circumference and resting systolic or diastolic pressure , pulse pressure , or mean blood 
 pressure ( p > 0.05 , table 2 ) . however , an 
 inverse correlation was observed between calf circumference and resting pulse rate for 1  min 
 ( r = 0.57 , p = 0.011 ; table 2 ) . although no correlation was observed between calf circumference and resting systolic or 
 diastolic pressure , pulse pressure or mean blood pressure , calf circumference correlated 
 inversely with resting pulse rate for 1  min . thus , we conclude that lower calf circumference 
 may be associated with high resting pulse rate . this finding may have implications for 
 practitioners for the prevention of adverse cardiovascular events in patients with smaller 
 calf circumference . in the soleus muscle of the triceps surae , the proportion of slow twitch muscle fiber is 
 almost 90%14 . lower capillary density is 
 associated with higher resting heart rate and mean blood pressure9 . the capillary density of slow twitch muscle fibers is 
 higher than that of fast twitch muscle fibers10 . therefore , in patients with smaller calf circumference , capillary 
 density in the soleus muscle may be lower and resting pulse rate may be higher . in addition , 
 an inverse correlation between stroke volume and heart rate has been demonstrated during 
 rest and exercise17 . stroke volume is 
 dependent on venous return ( the frank  starling principle ) , and venous return is dependent on 
 muscle pumping18 . the intramuscular pressure in the soleus during walking is about 180  20 mmhg , and 
 the soleus is more responsible than the tibialis anterior for pumping blood during 
 walking20 . venous return is dependent 
 on calf circumference21 ; therefore , in 
 patients with smaller calf circumference , the smaller soleus mass may result in reduced 
 muscle pumping , lower venous return , lower stroke volume , and increased resting pulse rate . thus , the 
 results of the present study indicate that calf circumference measurement may be used as a 
 screening test to determine resting pulse rate , and this information may be useful for the 
 prevention of cardiovascular events in older women . in the present study the product of heart rate and stroke volume is cardiac output ; in addition , 
 peripheral vessel resistance is a determinant of blood pressure . the rise and fall in blood 
 pressure is the results of a complex adaptation to stimulation rather than to pulse rate 
 alone . a low proportion of slow twitch muscle fiber results in higher vascular 
 resistance22 , and capillary density is 
 associated with systolic blood pressure , and endothelial function23 . on the other hand , a higher proportion of fast twitch 
 muscle fibers results in a higher resting mean blood pressure on account of muscular 
 sympathetic nervous activity24 . therefore , individuals amounts of fast twitch muscle fiber may have influenced resting 
 systolic or diastolic pressure , pulse pressure , and mean blood pressure in the present 
 study . one limitation of the present study is that the use of antihypertensive agents was not 
 investigated or analyzed . as beta - blockers have a direct influence on heart rate , the 
 relationships among calf circumference , blood pressure , and pulse rate with and without 
 antihypertensive drugs must be determined by another study . furthermore , the proportion of 
 slow or fast twitch muscle fibers , and capillary density were not measured ; therefore , it is 
 unclear how these factors influence calf circumference and resting pulse rate .
[ purpose ] high resting blood pressure and heart rate are associated with the risk of 
 cardiovascular events . in patients with decreasing amounts of slow twitch muscle fiber , 
 hypertension may develop and resting heart rate may increase . 
 measurement of the amount of 
 slow twitch muscle fiber and capillary density using muscle biopsy is inconvenient and 
 expensive . 
 therefore , a better screening test is required to determine these parameters 
 for prevention of cardiovascular events . in this study , relationships among calf 
 circumference , resting blood pressure , and pulse rate in the soleus muscle were 
 investigated . 
 [ subjects ] healthy elderly women ( n= 19 , 6184  years of age ) living in the 
 community were the subjects of this study . 
 [ methods ] blood pressure was measured using an 
 automatic hemodynamometer on the left arm . 
 the calf circumference was measured , and pulse 
 rate was measured on the left radial artery for 1  min by palpation . 
 [ results ] no 
 correlations were observed between calf circumference , resting systolic or diastolic 
 pressure , pulse pressure , or mean blood pressure . 
 however , an inverse correlation was 
 observed between calf circumference and resting pulse rate . 
 [ conclusion ] calf 
 circumference measurement may be used as a screening test for resting pulse rate . 
 this 
 test may be useful for the prevention of cardiovascular events .