Colon transit time according to physical activity level in adults.
OBJECTIVE
Physical activity (PA) is associated with a reduced risk of colorectal cancer. Thus, we examined the colon transit time (CTT) according to the physical activity level (PAL) in Korean adults.


METHODS
The study subjects were 49 adults: 24 males and 25 females. The subjects used an accelerometer for 7 consecutive days to measure the 1-week PAL. The subjects took a capsule containing 20 radio-opaque markers for 3 days. On the fourth day, a supine abdominal radiography was performed. According to the total activity count of all study subjects, the upper 25%, middle 50% and lower 25% were classified into the high (H), moderate (M) and low (L) physical activity (PA) groups, respectively.


RESULTS
The total CTT was significantly longer in the female (25.8 hours) than in the male subjects (7.4 hours) (P = 0.002). In regard to difference on PAL, although there was no significant difference among the male subjects, the right CTT in the female subjects was significantly shorter in H group than in M group (P = 0.048), and the recto-sigmoid CTT was significantly shorter in H group than in L group (P = 0.023). Furthermore, there were significant differences in total CTT between L and M groups (P = 0.022), M and H groups (P = 0.026) and between L and H groups (P = 0.002).


CONCLUSIONS
The female, but not male, subjects showed that moderate and high PAL assisted colon transit.
Health and Exercise Science Laboratory, Institute of Sports Science, Seoul National University, Seoul, Korea.
Bong Kil
BK
Song
Kang Ok
KO
Cho
Yunju
Y
Jo
Jung Woo
JW
Oh
Yeon Soo
YS
Kim