Is elbow breadth a measure of frame size in non-Caucasian populations? A study in low- and high-altitude Central-Asia populations

The concept of frame size has not undergone a thorough evaluation in non-Caucasian populations. Using data from the Central Asia High Altitude Population (CAHAP) study, we tested whether: (1) the relationship between frame size and body composition is different in high-, medium- and low-altitude populations; (2) elbow breadth is a better index of frame size than biacromial and biiliac breadth; and (3) measures of frame size are associated with blood pressure, cholesterol and triglycerides. A number of 334 male subjects aged 33 +/- 10 years (mean +/- standard deviation) were selected from the CAHAP population (n = 384) on the basis of the availability of breadth measurements. The subjects were 85 high-altitude Kirghizs, 105 medium-altitude Kazakhs, 79 low-altitude Kirghizs and 65 low-altitude Uighurs. A detailed anthropometric evaluation and blood pressure, cholesterol and trygliceride measurements were performed on all individuals. Among breadths, elbow had the lowest correlation with arm fat area, thigh fat area, calf fat area and the sum of trunk skinfolds (r < or = 0.196, P < 0.01). Even if elbow breadth did not have the highest correlation with muscularity indexes, its constantly lower association with adiposity indexes shows that it is a better measure of frame size than biacromial breadth and biiliac breadth. The relationship between frame size and body composition did not differ in high-, medium- and low-altitude subjects (P = not significant, analysis of co-variance). Only a weak association was present between breadths, blood pressure, cholesterol and triglycerides (r < or = 0.230, P < 0.01) and it was not influenced by altitude (P = not significant, analysis of co-variance). Elbow breadth was significantly correlated only with diastolic blood pressure (r = 0.121, P < 0.05). In conclusion: (1) the relationship between frame size and body composition is similar in high- and low-altitude populations; (2) elbow breadth is an index of frame size independent of altitude; and (3) elbow breadth is correlated with diastolic blood pressure, but this correlation is of doubtful biological relevance.