The impact of commuting on physical health

Building on the previous section, this section will consider the impact of commuting on our physical health. This is because, for many of us, our commute provides an opportunity to combine travel to and from our workplace with physical activity either in part or as a whole. Active commuting has been recognised as a feasible way of incorporating greater levels of physical activity into daily life, thereby helping meet recommended levels (NICE, 2012; WHO Regional Office for Europe, 2017). Undertaking physical activity has been well evidenced to be associated with: a reduction in various health outcomes, including cardiovascular disease, diabetes, some cancers and reducing the risk of premature mortality (Warburton et al., 2006; WHO, 2010; Department of Health (DH), 2011; Garber et al., 2011; Lee et al., 2012); improved mental health (Anokye et al., 2012; Cooper & Barton, 2015); and a reduction in anxiety (Anderson & Shivakumar, 2013). Previous studies have shown that significant levels of physical activity can be accrued during commuting, for example, 5 out of 26 workers in a UK-based study achieved minimum recommended physical activity guidelines (30 minutes of moderate-to-vigorous physical activity (MVPA) per day) in their commute alone, with commuting; accounting for 68% of total time in MVPA (Rafferty et al., 2016). Another study reported that participants recorded 55 minutes of MVPA per day and 30% of the recommended level of MVPA was accrued in commute (Yang et al., 2012). Therefore, the amount of physical activity accumulated during commuting could help to improve the health of the population in terms of both physical and mental health.

Despite the benefits of active commuting, travel distance from home to work, ineffective public transportation system, and convenience can act as barriers to uptake. Lengthy commute journeys can result in commuters taking a non-active mode of transport (Rafferty et al., 2016; RSPH, 2016); for example, in the UK from 1998 to 2016, of those who always used only one commute mode, 69% commuted to work as car/van drivers (the largest percentage) compared to 6% who walked (lowest 0% taxi/minicab) (Department for Transport, 2019). A major disadvantage of “non-active” lengthy commute journeys is also the association with increased levels of stress and increased time spent being sedentary (Christian, 2012b; The Work Foundation, 2016).

To support physical activity, allowing employees the flexibility of structuring their day by avoiding a rush-hour commute may enable workers to undertake activities that support healthier lifestyles (e.g. going for a run/swim or going to the gym, attending to other personal commitments,

Impact of commuting on mental and physical health 133 attending medical appointments or making a healthy meal) (RSPH, 2016). Further flexible working has been recognised as a way of reducing time spent during commuting, with almost 60% of commuters reporting that working remotely or flexibly helps to increase productivity (The Work Foundation, 2016), improve job satisfaction, and reduce stress (CIPD, 2019; Kelliher & Anderson, 2010). Although it should be noted that while different flexible working arrangements have been found to be beneficial, this is not always the case with flexible work hours that involve night shifts, often resulting in excessive fatigue, sleep disturbance, and gastrointestinal disorders (Costa et al., 2001).

Looking more specifically at the physiological effects of active commuting, it has been associated with a reduction in body mass index (BMI) and body fat percentage (BFP) (Flint et al., 2014; Flint et al., 2016; Mytton et al., 2018), reduced levels of hypertension and diabetes (Honda et al., 2015; Laverty et al.,

2013) , reduced cardiovascular risk (Celis-Morales et al., 2017; Gordon-Larsen et al., 2009; Panter et al., 2018), and reduced risk of metabolic syndrome (Garcia-Hermoso et al., 2018; Sadarangani et al., 2018; Steell et al., 2017).

Taking body fat as an example, evidence to support the benefits of active commuting by mode is seen in a cross-sectional study in the UK, which reported that commuters who cycled had lower body fat than those using a car, while those who walked regularly had no reduction in body fat (Mytton et al., 2018). A study conducted in India found that commuting by walking, cycling and public transport was associated with a lower likelihood of being overweight or obese and the associations remained after adjustment for potential confounders, including age, sex, standard of living, occupation, leisure-time physical activity, diet, and alcohol intake (Millett et al., 2013). Similarly, Rissel et al. (2014) used data from the New South Wales Continuous Health Survey to examine trends of walking and cycling over time from 2005 to 2010, concluding that Australian male and female workers that walked to work had a significantly lower BMI; however, cycling to work was associated with lower BMI in men only compared to other modes of commuting. This gender split was also found in a nationally representative UK study, which reported that compared to using private transport, walking and cycling to work were associated with lower BMI in men only (Flint et al.,

2014) . In a similar vein, a prospective UK cohort study that followed participants between April 2007 and December 2010 found that commuting by cycling and walking was associated with a lower risk of cardiovascular diseases, cancer outcomes and all-cause mortality, independent of BMI (Celis-Morales et al., 2017). In line with this finding, a longitudinal study that stratified commuters into regular (at least three days a week) and non-regular commuters, depending on whether they reported exclusive car use for commuting, found that regular commuters with active patterns of commuting had a lower risk of cardiovascular disease, and non-regular commuters with active patterns were associated with a lower risk of all-cause mortality compared to exclusive car users (Panter et al., 2018). This observation suggests that the frequency of commuting — at least three times a week — may influence ourhealth differently. Finally, for those commuters who do not have the option to actively commute, the adoption of flexible working may allow them the opportunity to engage in healthier activities during the day (Hilbrecht et al., 2014; R.SPH, 2016).

Section conclusion and practical initiatives

From the evidence it can be seen that there are significant benefits of active commuting on physical health, which are impacted by commute mode. However, most studies have classified active commuting as walking or cycling, with only a few including public transport. This has resulted in not capturing mixed-mode journeys, which is a major limitation. While commuting can be beneficial in terms of increasing physical activity levels, long commute journeys can increase the use of more passive modes of transport. Flexible working can provide an opportunity to engage in healthier activities, such as preparing healthy meals and exercising during what would have been the commute time.

Going forward, a recommendation to increase active and mixed-mode commuting may help to address environmental sustainability and increase physical activity in the population (Woodcock et al., 2007). We do recognise there are always likely to be commutes where active transport is not suitable, but future public policy and infrastructure should explore ways to encourage the use and development of low-energy transportation systems. Further to this consideration is the need to look into how to achieve commute modal shift on a population level. An example of this can be seen in countries such as the Netherlands, Denmark and Germany, where there are established infrastructures for transport such as safe and designated cycle lanes and a culture socialised towards cycling, the environment lends itself to active commuting, which is also coupled with the government having deterrents for driving in cities (e.g. taxes, and restrictions on parking and car ownership) (Pucher & Buehler, 2008). Finally, flexible working arrangements and having effective transportation systems can help improve the health of the working population, reallocate some rush-hour commutes to off-peak times, help increase the uptake of public transport due to less congestion outside of the rush-hour, and allow time for more active modes of commute (Ben-Elia & Ettema, 2011).