Neighbourhood walkability and greenspace and their associations with health-related fitness in urban dwelling Canadian adults.

Objective: Muscular strength and body composition are important components of health-related fitness (HRF). Grip strength and body fat percent, in particular, are associated with chronic disease and affected by health behaviours. Evidence suggests relationships between the neighbourhood built environment (BE) and HRF exist, however, few studies have focused on grip strength and body fat percent. Therefore, our study aimed to estimate the sex-specific associations between the neighbourhood BE, grip strength, and body fat percent among urban-dwelling Canadian adults.

Methods: We analyzed cross-sectional survey and HRF data collected in 2011-2015 from 4052 males and 7841 females (Alberta's Tomorrow Project, Canada). Grip strength and body fat percent were measured via handgrip dynamometry and bioelectrical impedance analysis, respectively. Walkability (Canadian Active Living Index) and greenness (Normalized Difference Vegetation Index) estimates were linked to participant data. Sex-stratified covariate-adjusted linear regression models estimated the associations between the BE and HRF variables.

Results: Walkability was negatively associated with grip strength and body fat percent in males (β -0.21, 95%CI: -0.31 to -0.11 and β -0.08, 95%CI: -0.15 to -0.02, respectively) and females (β -0.06, 95%CI: -0.10 to -0.01 and β -0.08, 95%CI: -0.14 to -0.02, respectively). Greenness was positively associated with grip strength in males (β 6.99, 95%CI: 3.62 to 10.36) and females (β 2.72, 95%CI: 1.22 to 4.22) but not with body fat percent. Controlling for physical activity and sitting did not attenuate these associations.

Conclusion: Characteristics of the neighbourhood BE appear to be associated with muscular strength and body composition, independent of physical activity and sedentary behaviour.