1.Frequent coffee drinking is associated with higher leg extension power among adult men : a cross-sectional study
Masahiko Chujo ; Kaijun Niu ; Haruki Momma ; Yoritoshi Kobayashi ; Lei Guan ; Mika Sato ; Hui Guo ; Atsushi Otomo ; Yufei Cui ; Hiroko Tadaura ; Tatsunori Saito ; Ryoichi Nagatomi
Japanese Journal of Physical Fitness and Sports Medicine 2014;63(4):383-389
Coffee administration has been shown to increase maximum voluntary contraction and muscular endurance. However, no study has addressed the association between daily consumption of coffee with muscular function. This cross sectional study aimed to investigate the association between frequency of coffee consumption (CC) in daily life and muscle strength among a population of working adult men. This cross sectional study included men (n = 516, mean age: 47.1) who participated in an annual health examination conducted in Sendai. The monthly frequency of coffee consumed was reported by a brief-type self-administered dietary history questionnaire. Leg extension power (LEP) was measured as an index of muscle strength. Subjects were divided into tertile levels according to CC. Analysis of covariance was used to examine the relation between the tertile levels of CC and LEP. After adjustment for potential confounders (including all lifestyle factors), the adjusted means (95% confidence interval) of LEP across the tertiles of CC were 17.4 (16.6 - 18.1) for the lowest tertile, 17.9 (17.4 - 18.5) for the mid tertile, and 18.9 (18.3 - 19.5) for the highest tertile (p for trend = 0.007). Higher frequency of monthly coffee consumption was associated with higher muscle strength.