A "gender blind" relationship of lean body mass and blood pressure in the Tecumseh study.

Background: Body size correlates positively with blood pressure (BP) but there is controversy about the roles of obesity versus muscularity in this relationship.

Methods: We examined the BP relationship with overweight, lean body mass (LBM), and muscle performance in 231 adolescents (17.25 +/- 3.07 years, 123 males). The skinfold thickness (SKINT) was used to measure overweight, as this was a growing population.

Results: Maximal foot torque, a measure of muscle strength, correlated strongly (r = 0.51, P < .001) to LBM attesting to the validity of the calculated LBM. Anthropometric measurements were available also in 944 adults (29.9 +/- 5.5 years, 461 men). Correlations of LBM to systolic (adolescents r = 0.52, adults r = 0.19, both P < .001) and diastolic (adolescents r = 0.47, adults r = 0.20, both P < .001) BP were highly significant. SKINT also correlated significantly to systolic and diastolic BP in adolescents and in adults, respectively. In both genders and populations an increasing SKINT was associated with a similar increase in BP, but this effect was superimposed on an average 10 mm Hg between-gender BP difference. The LBM in both groups and genders related to the BP in an identical fashion; the men were on the high and the women on the low end of the same BP/LBM correlation line. Thus, the amount of LBM erased categoric BP differences between the genders.

Conclusions: The gender-related BP differences appear to reflect the inherent gender differences in muscle bulk.