For the climate, please stop to support the FC Bayern Munich ! 

What is the related travel annual carbon footprint of German Football Bundesliga fans ?

Two German researchers collected the following self-reported data about age, sex, level of education, income, environmental values, club membership, favorite team and travel behavior in relation home and away matches (for 2018/19 season) via an online questionnaire (1). They included 539 fans and >50% of respondents were a member of their favorite club.

  • The average seasonal carbon footprint / fan was 311 kg CO2 eq (almost 3% of annual carbon footprint for a German)
  • Highest carbon footprints were found for FC Bayern Munich & RB Leipzig (i.e., 673.8 and 387kg CO2 eq )
  • Private car was the most used frequent mode of transport

The following factors were associated with higher carbon footprint: club membership, fan of Bayern or Leipzig. It’s important to note that income and environmental values were not significantly associated.

This study is a first approach of carbon footprint sport fans. The relative low carbon footprint associated with travels is relatively specific (i.e., geographical scale but also train and public transport availability). It should be very different, if same data were collected in NHL or NBA fans.

1. Loewen C, Wicker P. Travelling to Bundesliga matches: the carbon footprint of football fans. Journal of Sport & Tourism. 2021 May 27;0(0):1–20.  

Impacts of wildfires on physical activity

I write this blog article during an important forest fire in British Columbia (Canada), occurring during an extreme heat wave in the same geographical area. The last Lancet report on health and climate change called it : the ‘converging crises’ (1). Climate projections indicate wildfires will increase in frequency and intensity in the U.S, Canada, Australia, Russia… What are the effects of wildfires on physical activity patterns ?

Cruz et al examined the effects of bushfires on accelerometer measured physical activity among exposed and control children (245 vs 344, 8-10 years, Australia) (2). Additionally, they modelized the association between Air Quality Index (AQI) and moderate to vigorous physical activity (MVPA) in exposed children (with sub analyses for sex and socioeconomic status). Authors collected PA data for their multi-center interventional study, and the bushfires occurred between the end of intervention and first follow-up measures. Children were classified as affected by bushfires if they were exposed to AQI >100 for 3 consecutive days, and their school received targeted advice to avoid outdoor Pas. Their statistical analyses were well-adapted and sophisticated.

Children’s physical activity was not strongly influenced by the presence of smoke during bushfires. Findings were similar for MVPA, VPA, MPA during or outside school hours or after the inclusion of temperature as covariable. During the school time, an AQI of 1 standard deviation increase was associated with a decrease of 2 and 0.6 daily minutes for MPA and VPA, respectively. The curvilinear models suggested that AQI >737 (AQI > 200 = ‘hazardous’) was associated with a drastic MVPA reduction among exposed children. This ‘tipping point’ was not different for children with living in family with low or high socioeconomic background.

Authors suggested that the relative stable PA level during the wildfire episode may be explained by a possible PA indoor practices or family/teachers might not follow the Australian Education Department recommendation about outdoor PA restrictions. Consequently, the children might have been exposed to high level of air pollution.

A US study examined the association between four AQI classes (ranged from moderate to hazardous air quality) and daily number of steps (measured with fitbit) among adults living in California during 2017-2018 wildfire seasons (N > 1000) (3). A significant 18% reduction in daily step count was found when the AQI exceeded 200 compared with AQIs < 100. Similar results were observed after multivariable adjustment, but sex was missing among the covariables.

Finally, another PA characteristic has been examined: active travel in urban context. Doubleday et al. (4) used the bicycle and pedestrian counters data in Seattle (Washington state) to examine the effects of wildfire smoke events. They compared daily bicycle and pedestrian counts across 3 periods, 20 days before wildfires, during wildfire (>3 consecutive days with PM2.5 >15), and 20 days after.

A significant decrease of active travel frequency was observed during the second and larger of two wildfire smoke events (2018, see figure). Findings also showed a slow return to pre-wildfire smoke event physical activity levels in some areas.

This significant PA decrease could be observed only for 2018 because wildfire smoke events were more intense, but also by an improvement of risk reduction messages dissemination by local authorities.



  • 1. Watts N, Amann M, Arnell N, Ayeb-Karlsson S, Beagley J, Belesova K, et al. The 2020 report of The Lancet Countdown on health and climate change: responding to converging crises. The Lancet. 2021 Jan;397(10269):129–70.
  • 2. del Pozo Cruz B, Hartwig TB, Sanders T, Noetel M, Parker P, Antczak D, et al. The effects of the Australian bushfires on physical activity in children. Environment International. 2021 Jan 1;146:106214.
  • 3. Rosenthal DG, Vittinghoff E, Tison GH, Pletcher MJ, Olgin JE, Grandis DJ, et al. Assessment of Accelerometer-Based Physical Activity During the 2017-2018 California Wildfire Seasons. JAMA Network Open. 2020 Sep 30;3(9):e2018116.
  • 4. Doubleday A, Choe Y, Busch Isaksen TM, Errett NA. Urban bike and pedestrian activity impacts from wildfire smoke events in Seattle, WA. Journal of Transport & Health. 2021 Jun;21:101033.

Canadian universities : where is the climate change ?

I share my text published in University Affairs.

When I tell my colleagues that I’m trying to examine the links between physical activity, sports and climate change, the most common response is still: What’s the connection? My research focuses more generally on questions of health psychology. But after reading a number of books, opinion pieces, and especially the report from the Intergovernmental Panel on Climate Change, I’ve had something of a rude awakening. For example, over 15,000 researchers have sounded the alarm to remind us that humanity is in danger if we continue to exceed the Earth’s biophysical limits.

The efforts that will be needed to limit temperature increases to less than 2°C by 2050 are enormous. Canadians have one of the largest annual carbon footprints in the world (about 17.5 tons of carbon), which we will need to reduce to about two tons per person within 30 years.

While our university colleagues in climatology, geology and other fields have been doing a remarkable job of communicating these issues, we must be realistic: the necessary changes are not happening. Greenhouse gas emissions continue to increase in Canada. Other university researchers are making progress on climate issues in their respective disciplines, but remain isolated from one another. The next decade will be decisive for future generations. We need to find ways to leverage our combined efforts to make rapid progress, to an even greater extent than our response to COVID-19. To help achieve this, the entire university community should engage with this issue by systematically incorporating questions of climate change and the collapse of biodiversity into introductory courses. The students we teach will be on the front lines when it comes to managing the challenges associated with climate change. Philosophy, law, economics, health sciences, political science, engineering, the arts… All disciplines are affected by climate concerns.

Paradoxically, climate issues do not seem to be a central topic in the courses taught at Canada’s postsecondary institutions. An analysis of course syllabi suggests that less than half of the institutions surveyed were addressing climate change in 2014-15. In other countries, however, a number of initiatives have already been developed, from integrating climate issues into existing courses to the development of interdisciplinary degree programs or educational activities. We can start this process right now by integrating climate issues within general courses, developing a mandatory “climate change education” module as a requirement for earning a university degree, developing new interdisciplinary degree programs in environmental sciences that systematically incorporate ethical and social justice issues, or develop introductory workshops for students on basic climate and energy issues. There are a number of peer-to-peer initiatives in which students can serve as educators to their younger peers, such as the Climate Collage and the Carbon Literacy Project, as well as the online course entitled Changements climatiques et santé (Climate Change and Health) developed by the Institut national de santé publique du Québec.

Our teaching is connected to our research activities. As such, academics should be financially supported and encouraged by their governing bodies to develop research projects on climate issues within their field of expertise, or to take part in multi- and transdisciplinary projects. Unsurprisingly, the lack of funding for university research on climate change remains the biggest obstacle for researchers. Therefore, Canadian universities and granting agencies should make it an urgent priority to reorient their policies to favour research projects that focus directly or indirectly on reducing greenhouse gas emissions, and on the varying degrees to which Canada’s different communities are prepared to face the consequences of climate change.

Of course, investing time and energy on this issue is likely to slow down other projects, but the sacrifice is well worth it. Climate change will cause profound and sudden changes in our ways of living, consuming and producing. In Canada, coastal erosion is already forcing residents of the North Shore area to relocate. In addition, the country we live in is ranked 58th out of 61 on the climate change performance index. Not to mention that the countries at greatest risk of climate catastrophes are generally those with the least resources to deal with them.

Finally, it should be noted that young people clearly have an interest in climate change (ex. There were 400,000 participants at a Montreal demonstration in 2019), which could translate to significant investment in climate issues in their university studies, regardless of their chosen field.

Content of behavior change interventions for more sustainable diet behaviors.

The definition of sustainable diet varies between the authors and countries (1). However, the main characteristics are provided by Lonnie et al. (2) : to consume a variety of unprocessed or minimally processed foods, (i.e., whole-grains, pulses, fruits and vegetables), with moderate amounts of eggs, dairy, poultry and fish and modest amounts of ruminant meat . The Food and Agriculture Organization has published a more broad definition of sustainable diet: ‘Sustainable diets are protective and respectful of biodiversity and ecosystems, culturally acceptable, accessible, economically fair and affordable; nutritionally adequate, safe and healthy; while optimizing natural and human resources’ (3).

As you can imagine, it is particularly challenging to operationalize the sustainable diet behaviors for future interventions. A behavioral intervention could target the adopting plant-based diet, decrease the consumption of meats, sugar added product, ultra-processed food, soda, dairy products (particularly cheese)…. The behavioral change perspectives of sustainable diet are in line with debates about multiple health behavior change interventions (i.e., sequential versus simultaneous approach, number and order of targeted behaviors, rebound effects…) (4–6).

I tried to identify the systematic reviews examining the effects of ‘real-context’ behavioral interventions to help adults to adopt more sustainable diet behaviors. No surprise ! Most of published papers focused on animal-based diet or adoption of plant-based diets. It is easily understandable because the meat consumption reduction is particularly interesting in term of individual carbon footprint reduction (7,8) and is associated with various health benefits. Furthermore, the reduction of red and processed meat is also associated with a decrease of water and ecological individual footprints (9).

Five reviews and one report was found (10–15). I also added two narrative reviews of the special issue of Current Opinion in Behavioral Sciences about climate change (16,17). The number of interventions was relatively low and their respective efficacy is disputable. Most of interventions were performed in a ‘controllable’ context (e.g., cafeteria).

What are the psychological targets (and possible behavioral change techniques) to develop a future effective behavior change intervention ?

  • Health beliefs (to provide the information about health benefits or consequences) (10,11,14)
  • Food knowledge (to develop the skills and abilities preparation of new food or plant-based meals) (10,11,14)
  • Environmental beliefs (to provide the information about environmental benefits or consequences) (14,15)
  • Self-regulation (to facilitate action planning, to prompt self-recording) (11,14)

What are the most recurrent psychological barriers ?

  • Positive taste experiences with meat (10,12)
  • Health risks perception associated with a diet without meat (10,12)
  • Food preparation or purchase habits (10,10,13)
  • Poor social support or unwillingness of household members (10,13)

It is important to note that the findings are only generalizable in adults living in countries with high-incomes. Also, higher incomes and levels of education were associated with easier shift from meat- to plant-based diets (11,13).

The review about habit and climate change suggested that implementation intentions and gamification may be two effective technique to disrupt the meat consumption (17). Finally, the reported studies in review about the affects and emotions for climate change communication were mostly experimental. However, the authors suggested the ineffective role of threatening messages to modify the health behavior has not been verified for pro-environmental behaviors (16).

This article is a first attempt to identify the evidence based contents of future sustainable diet interventions. I recommend the well-designed protocol of Bianchi et al. , particularly their intervention logic model.

  • 1. Steenson S, Buttriss JL. The challenges of defining a healthy and ‘sustainable’ diet. Nutrition Bulletin. 2020;45(2):206–22.
  • 2. Lonnie M, Johnstone AM. The public health rationale for promoting plant protein as an important part of a sustainable and healthy diet. Nutrition Bulletin. 2020;45(3):281–93.
  • 3. Food Forum, Food and Nutrition Board, Health and Medicine Division, National Academies of Sciences, Engineering, and Medicine. Sustainable Diets, Food, and Nutrition: National Academies Press; 2018. Available from:
  • 4. Hyman DJ, Pavlik VN, Taylor WC, Goodrick GK, Moye L. Simultaneous vs Sequential Counseling for Multiple Behavior Change. Archives of Internal Medicine. 2007 Jun 11;167(11):1152.
  • 5. Sniehotta FF, Presseau J, Allan J, Araújo-Soares V. “You Can’t Always Get What You Want”: A Novel Research Paradigm to Explore the Relationship between Multiple Intentions and Behaviours. Applied Psychology: Health and Well-Being. 2016 Jul;8(2):258–75.
  • 6. Spring B, Moller AC, Coons MJ. Multiple health behaviours: overview and implications. Journal of Public Health. 2012 Mar 1;34(suppl 1):i3–10.
  • 7. Bernard P. Health psychology at the age of Anthropocene. Health Psychology and Behavioral Medicine. 2019 Jan 1;7(1):193–201.
  • 8. Ivanova D, Barrett J, Wiedenhofer D, Macura B, Callaghan M, Creutzig F. Quantifying the potential for climate change mitigation of consumption options. Environ Res Lett. 2020 Aug;15(9):093001.
  • 9. Fresán U, Marrin DL, Mejia MA, Sabaté J. Water Footprint of Meat Analogs: Selected Indicators According to Life Cycle Assessment. Water. 2019 Apr;11(4):728.
  • 10. Graça J, Godinho CA, Truninger M. Reducing meat consumption and following plant-based diets: Current evidence and future directions to inform integrated transitions. Trends in Food Science & Technology. 2019 Sep;91:380–90.
  • 11. Taufik D, Verain MCD, Bouwman EP, Reinders MJ. Determinants of real-life behavioural interventions to stimulate more plant-based and less animal-based diets: A systematic review. Trends in Food Science & Technology. 2019 Nov;93:281–303.
  • 12. Szejda K, Urbanovich T, Wilks M. An Evidence-Based Guide for Effective Practice. :111.
  • 13. Fehér A, Gazdecki M, Véha M, Szakály M, Szakály Z. A Comprehensive Review of the Benefits of and the Barriers to the Switch to a Plant-Based Diet. Sustainability. 2020 May 19;12(10):4136.
  • 14. Bianchi F, Dorsel C, Garnett E, Aveyard P, Jebb SA. Interventions targeting conscious determinants of human behaviour to reduce the demand for meat: a systematic review with qualitative comparative analysis. International Journal of Behavioral Nutrition and Physical Activity [Internet]. 2018 Dec [cited 2021 May 14];15(1).
  • 15. Abrahamse W. How to Effectively Encourage Sustainable Food Choices: A Mini-Review of Available Evidence. Frontiers in Psychology [Internet]. 2020 Nov 16 [cited 2021 May 14];11. Available from:
  • 16. Brosch T. Affect and emotions as drivers of climate change perception and action: a review. Current Opinion in Behavioral Sciences. 2021 Dec 1;42:15–21.
  • 17. Verplanken B, Whitmarsh L. Habit and climate change. Current Opinion in Behavioral Sciences. 2021 Dec;42:42–6.

What is the effectiveness of psychological interventions to reduce car using? 

A recent meta-analysis modeled the effects of psychological interventions (calledsoft interventions’) on car use (1). Most of included studies targeted the perceptions, beliefs, attitudes, values, and norms of participants. Three previous meta-analyses found a small effect size (h ranged from .12 to .16) or no effect on car use reduction (2).

The current meta-analysis included the published paper with a more robust method (i.e., experimental or quasi-experimental design), published in the past 30 years. The aims were to quantify the effect of psychological interventions and to identify the most important moderators. The following moderators were examined with uni-variate models : type of outcomes (e.g., number of trips versus traveled distance), type of intervention (e.g., information + free public transport ticket), psychological variable targeted (e.g., attitudes, habit, knowledge, self-efficacy, social norms), relocated participants, and study design. The authors also examined moderator effect of the percentage of women, incentives, city size by including the psychological variables targeted in models. 

No surprise ! 

Their meta-analysis was based on 41 interventions. They found significant and small effect size (g = 0.163, p < .001, 95% CI [0.11, 0.21]). The most interesting results were in the following findings.  As you can see, the most effective interventions targeted the social cultural and moral norms (g = 0.73), knowledge and awareness (g = 0.348) and those targeting capability and self-efficacy, (g = 0.12). 

The efficacy of interventions targeting relocated car users were not higher than other interventions. The other tested moderators (e.g., % of women) were not significant when the models were adjusted for psychological variables targeted in interventions. 

In conclusion, the decrease of car use after a psychological intervention, expressed in percentages, is approximately 7% ! In other words, the psychological interventions are not the panacea to decrease the car use. The ‘hard interventions’ are, for the moment, the most effective solutions (i.e., altering the physical environment (e.g., closing roads, building bicycle lanes, etc.) or legal or economic policies (e.g., prohibiting car traffic in city centers, congestion pricing, introducing parking fees).  

The future behavioral or psychological interventions should target the social and cultural norms in their interventions. Finally, I think that the academic psychology community should be humbler on this question (3).

  • 1. Semenescu A, Gavreliuc A, Sârbescu P. 30 Years of soft interventions to reduce car use – A systematic review and meta-analysis. Transportation Research Part D: Transport and Environment. 2020 Aug;85:102397.
  • 2. Arnott B, Rehackova L, Errington L, Sniehotta FF, Roberts J, Araujo-Soares V. Efficacy of behavioural interventions for transport behaviour change: systematic review, meta-analysis and intervention coding. International Journal of Behavioral Nutrition and Physical Activity [Internet]. 2014 Dec;11(1).
  • 3. Bernard P. Health psychology at the age of Anthropocene. Health Psychology and Behavioral Medicine. 2019 Jan 1;7(1):193–201. 
Rechercher dans OpenEdition Search

Vous allez être redirigé vers OpenEdition Search