There is growing scientific evidence that active commuting, such as cycling and walking, positively affects overall health, including a reduced risk of cardiovascular disease (CVD), cancer, all-cause mortality, and improved mental health. However, the exact mechanism by which active commuting influences health outcomes has yet to be elucidated.
Study: The association between commuting and cardiovascular disease: A biomarker-based analysis of cross-sectional cohort data from the UK Biobank. Image Credit: Dean Dobot / Shutterstock.com
About the study
In a recent article published in the journal Preventive Medicine, researchers estimate the influence of active and passive commuting modes on CVD outcomes based on relevant biomarker levels. In addition to biomarker data obtained from 208,893 United Kingdom Biobank baseline survey participants, the researchers also examined how the intensity and type of commuting altered CVD biomarker levels.
The eight biomarkers analyzed in this study included total cholesterol, triglycerides, low-density lipoprotein (LDL), high-density lipoprotein (HDL), apolipoprotein A and B, C-reactive protein (CRP), and lipoprotein a. For each biomarker, the researchers determined whether the respective value reflected an increased risk of developing CVD.
In the cross-sectional U.K. Biobank survey, researchers recruited participants aged 40 to 69 between 2006 and 2010 from 22 centers in England, Scotland, and Wales. All recruited participants used various transportation modes to commute to work at least once each week.
Each participant's sociodemographic and health-related information was also provided, including biological parameters such as body fat and grip strength and lifestyle indicators like diet and physical activity levels.
Study findings
Of all 208,893 survey respondents, 165,540 used cars as a mode of transportation, while only 5,883 respondents regularly commuted to work by bicycle. Around 38% of bicycle commuters also engaged in cycling/walking in their free time, which was significantly greater than the 8% of car commuters who frequently participated in these activities.
Study participants who frequently walked to work were associated with a significantly lower risk of low HDL and apolipoprotein A as compared to those who drove to work. Comparatively, cycling to work was associated with a lower risk for high triglycerides, low apolipoprotein A, high or low apolipoprotein B, and high CRP levels.
When the researchers increased the commuting time for passive commuters by an additional 10 miles each week, their relative risk of high total cholesterol, LDL, and triglycerides levels increased, as well as their risk of low apolipoprotein A and high/low apolipoprotein B levels.
Comparatively, every additional mile added to the commute of those who frequently walked to work further lowered their risk of high triglycerides. Any additional miles did not alter the projected biomarker levels for those who cycled or used public transportation.
About 16% of bicycle commuters never ate processed meat as compared to 10% of car commuters, thus suggesting even the dietary habits of these individuals were also significantly different. Moreover, cycling commuters covered an average of 34 miles each week and burnt up to 2,000 additional kcal, depending on the intensity of their cycling that day.
Another personal factor that impacted the results was the individual’s waist-to-hip ratio. To this end, those with a higher waist-to-hip ratio, as well as those who were currently prescribed CVD medication, were less likely to cycle or walk to work.
Conclusions
The study findings demonstrate that both walking and cycling to work are associated with significant cardiovascular health benefits. The correlation of these health benefits to certain biomarker levels suggests a mechanism by which physical activity reduces CVD incidence and mortality.
CVD biomarker levels did not differ significantly between those who took public transportation, including buses, subways, and trains. In addition to commuting mode and distance, other factors, such as the quality of public transport, work-time arrangements, climate, and even childcare facilities. could contribute to the health effects associated with different commuting practices. Therefore, more research is needed to better understand how commuting by public transport and other factors may impact physical health.
One of the key strengths of this study is its large sample size and the wide range of biomarkers that were used. Nevertheless, the cross-sectional nature of this study, combined with the potential impact of certain residual confounding factors, are important limitations to these findings.
Journal reference:
- Kaiser, M., Bauer, J. M., Otterbach, S., et al. (2023). The association between commuting and cardiovascular disease: A biomarker-based analysis of cross-sectional cohort data from the UK Biobank. Preventive Medicine. doi:10.1016/j.ypmed.2023.107521