Pumping Iron in Australia: Prevalence, Trends and Sociodemographic Correlates of Muscle Strengthening Activity Participation from a National Sample of 195,926 Adults

Abstract

Objective: The current Australian Physical Activity Guidelines recommend that adults engage in regular muscle-strengthening activity (e.g. strength or resistance training). However, public health surveillance studies describing the patterns and trends of population-level muscle-strengthening activity participation are sparse. The aim of this study is to examine the prevalence, trends and sociodemographic correlates of muscle-strengthening activity participation in a national-representative sample of Australians aged 15 years and over.

Methods: Between 2001 and 2010, quarterly cross-sectional national telephone surveys were conducted as part of the Australian Sports Commission's 'Exercise, Recreation and Sport Survey'. Pooled population-weighted proportions were calculated for reporting: [i] no muscle-strengthening activity; [ii] insufficient muscle-strengthening activity, and [iii] sufficient muscle-strengthening activity. Associations with sociodemographic variables were assessed using multiple logistic regression analyses.

Results: Out of 195,926 participants, aged 15-98 years, only 10.4% (95% CI: 10.1-10.7) and 9.3% (95% CI: 9.1-9.5) met the muscle-strengthening activity recommendations in the past two weeks and in the past year, respectively. Older adults (50+ years), and those living in socioeconomically disadvantaged, outer regional/remote areas and with lower education were less likely to report sufficient muscle-strengthening activity (p<0.001). Over the 10-year monitoring period, there was a significant increase in the prevalence of sufficient muscle-strengthening activity (6.4% to 12.0%, p-value for linear trend <0.001).

Conclusions: A vast majority of Australian adults did not engage in sufficient muscle-strengthening activity. There is a need for public health strategies to support participation in muscle-strengthening activity in this population. Such strategies should target older and lower educated adults, and those living in socioeconomically disadvantaged, outer regional/remote and areas.

Fig 1. Overview of Exercise, Recreation and Sport Survey (ERASS) responses for muscle-strengthening (MS) activity^a prevalence levels reported by weighted counts and percentages (%) and their 95% confidence intervals (95% CI)—pooled responses for 2001–2010 (12-month recall) & 2005–10 (2-week recall).

^aMuscle-strengthening activities include combined activities assessed within the Exercise, Recreation and Sport Survey (ERASS) 2001–10: Calisthenics, Gymnasium workouts, Military exercise, Prime movers (over 50s), Body building, Circuits, Power team, Weight training for fitness, & Weightlifting (for competition) [20].