title: Perceptions and the role of group exercise among New York City adults, 2010-2011: an examination of interpersonal factors and leisure-time physical activity.
abstract: OBJECTIVE
  To examine associations of descriptive norms (i.e., behaviors of social group members) and exercising 'with a partner' or 'as a part of a group' on weekly leisure-time physical activity.
  
  
  METHODS
  T-tests and adjusted multivariable linear models were used to test the associations between descriptive norms and exercising with a partner or as a part of a group with self-reported leisure-time physical activity using the cross-sectional, population-based New York City Physical Activity and Transit (PAT) Survey 2010-2011 (n=3806).
  
  
  RESULTS
  Overall, 70.6% of adult New Yorkers reported having physically active friends. Having active friends was associated with increased leisure-time physical activity; however, the effect varied by sex. Compared to those who did not have active friends, males with active friends reported two times more activity (56 min/week) and women reported two and a half times more activity (35 min/week) (both p-values<0.001). Physically active males and females who usually engaged in leisure-time activities as a part of a group reported 1.4 times more activity than those who exercised alone (both p-values<0.03).
  
  
  CONCLUSIONS
  Descriptive norms and group exercise were associated with leisure-time physical activity among adults. Based on these associations, encouraging group exercise may be an effective strategy for increasing leisure-time physical activity among certain subgroups.
authors.affiliation: NYC Department of Health and Mental Hygiene, USA. Electronic address: mfirestone@health.nyc.gov.
authors.forename: Melanie J
authors.initials: MJ
authors.lastname: Firestone
authors.affiliation: NYC Department of Health and Mental Hygiene, USA; Department of Population Health, New York University School of Medicine, USA.
authors.forename: Stella S
authors.initials: SS
authors.lastname: Yi
authors.affiliation: NYC Department of Health and Mental Hygiene, USA.
authors.forename: Katherine F
authors.initials: KF
authors.lastname: Bartley
authors.affiliation: NYC Department of Health and Mental Hygiene, USA.
authors.forename: Donna L
authors.initials: DL
authors.lastname: Eisenhower
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D015444:Exercise / Q000523:psychology*; D005260:Female; D006126:Group Processes; D006801:Humans; D007398:Interpersonal Relations; D007899:Leisure Activities / Q000523:psychology*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009519:New York City; D012944:Social Support; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Descriptive norms; GPAQ; Group exercise; LTPA; Physical activity