Relationship between the type and amount of physical activity and low back pain in Koreans aged 50 years and older.
OBJECTIVES
To examine the association between the type and amount of physical activity (PA) and low back pain (LBP) in people aged ≥50 years.


DESIGN
Cross-sectional study.


SETTING
A nationwide survey.


PARTICIPANTS
Data were obtained from the Fifth Korea National Health and Nutrition Examination Survey, which was conducted in 2010 and 2011. Overall, 1796 men and 2198 women aged ≥50 years were included.


METHODS
PA was categorized as vigorous, moderate, walking, strength exercises, or flexibility exercises. The total amount of PA was presented as quartiles of the total metabolic equivalent (MET)-minutes/week based on the PA questionnaire. Multivariate logistic regression analysis was performed to examine associations between LBP and the type and amount of PA.


MAIN OUTCOME MEASUREMENTS
Odds ratio for LBP according to the type of PA and the quartiles of the total MET-minutes/week.


RESULTS
After adjusting for age and body mass index, vigorous and moderate PA were associated with an increased risk of LBP in both men and women, whereas strength exercises were associated with a reduced risk of LBP. These associations were maintained after adjusting for all potential confounders. Subgroup analysis according to age revealed that these trends were most significantly demonstrated in women aged ≥65 years. The PA quartiles for total MET-minutes/week for men showed a U-shaped association with LBP, whereas only the fourth PA quartile for women showed an increased risk of LBP compared with the second quartile.


CONCLUSIONS
These results suggest that both the type and amount of PA affect the development of LBP in people aged ≥50 years and thus activity modification might be helpful for prevention and management of LBP.