title: Physical Activity and Gastric Cancer Risk: A Systematic Review and Meta-Analysis.
abstract: OBJECTIVE
  Physical activity represents a well-established way to prolong the life span; yet, it remains an unfulfilled goal for a great part of the population. In parallel, the burden of gastric cancer is considerable throughout the globe. In that context, the present meta-analysis aims to shed light on the association between physical activity and gastric cancer risk.
  
  
  METHODS
  Eligible observational studies were sought in PubMed up to June 01, 2015. In addition, a snowball procedure was conducted and contact with authors was implemented. Separate analyses were performed by type of physical activity (total; occupational; recreational), study design, published/provided data, anatomical site, and study location, along with stratification by gender.
  
  
  RESULTS
  Ten cohort studies (7551 incident cases in a total cohort size of 1 541 208 subjects) and 12 case-control studies (5803 cases and 73 629 controls) were eligible. "Any" type of physical activity was associated with lower risk of gastric cancer [pooled relative risk (RR) = 0.81; 95% CI: 0.73 to 0.89], which was reproducible in men (pooled RR = 0.87; 95% CI: 0.77-0.99). The protective effect was significant in the subgroup analyses of published data, noncardia cancer (pooled RR = 0.62; 95% CI: 0.52-0.75), and studies stemming from Asia (pooled RR = 0.82; 95% CI: 0.74-0.90).
  
  
  CONCLUSIONS
  This meta-analysis suggests a protective effect of physical activity regarding gastric cancer risk, especially in Asian populations.
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece.
authors.forename: Theodora
authors.initials: T
authors.lastname: Psaltopoulou
authors.forename: Ioannis
authors.initials: I
authors.lastname: Ntanasis-Stathopoulos
authors.forename: Ioannis-Georgios
authors.initials: IG
authors.lastname: Tzanninis
authors.forename: Maria
authors.initials: M
authors.lastname: Kantzanou
authors.forename: Despoina
authors.initials: D
authors.lastname: Georgiadou
authors.forename: Theodoros N
authors.initials: TN
authors.lastname: Sergentanis
mesh_terms: D044466:Asian People; D015444:Exercise; D006801:Humans; D013274:Stomach Neoplasms / Q000517:prevention & control*