The idea that football can be used as therapy and as a high-intensity and literally breath-taking training regime goes back centuries. To take one prominent example, the French philosopher Voltaire describes in the Book of Fate (1747), how a patient is cured by playing with a sacred football: “… full-blown and carefully covered with the softest Leather. You must kick this Bladder, Sir, once a Day about your Hall for a whole Hour together, with all the Vigour and Activity you possibly can”, “Ogul, upon making the first Experiment, was ready to expire for want of Breath”, “In short, our Doctor in about 8 days Time, performed an absolute Cure. His Patient was as brisk, active and gay, as One in the Bloom of his Youth.”1 Today, Voltaire and his main character, philosopher Zadig, have been proved right: Football is indeed a breath-taking activity and it can be used as therapy. Albeit today's recommendations suggest a lower training frequency, longer training periods and encourage group-based training, and say that any football can be applied… Today comprehensive research has shown that small-sided football is an intense, versatile combination of strength, endurance and aerobic high-intensity interval training and that twice-weekly 1-hour sessions can be utilized for the prevention, treatment or rehabilitation of non-communicable diseases, such as hypertension, type 2 diabetes, osteopenia and prostate cancer.2-5 Likewise, various school and football club projects have shown that football has great potential to increase fitness, psycho-social well-being, motor skills, cognitive functioning, and learning.6-8 During the last century, the scientific study of football focused almost entirely on elite football. However, as of the early 2000s investigations into the fitness and health effects of football were initiated.2 The evidence regarding the application of football as a health-enhancing activity for the general population is currently expanding rapidly with more than 150 scientific articles published over the last 10 years in 35 peer-reviewed international journals, including three meta-analyses,9-11 three narrative reviews,3-5 three special issues on Football for Health12-19 and one on football, basketball, team handball, and other team sports.20 The overall conclusions are summarized in the “Football is Medicine”-model, integrating sports science, sport training physiology, sports medicine, sports psychology and sports sociology results (Figure 1).2 The three special issues on Football for Health have all been published in the Scandinavian Journal of Medicine and Science in Sports and they tell a unique story about the development of the research and the gradually increasing focus on football as therapy. The first was published in 2010 focusing on “Football as prevention”,12-14 the second in 2014 expanded on the work on “Football as prevention and treatment”,15-19 and the present special issue published in 2018 is entitled “Football is Medicine” and emphasizes the comprehensive results and the huge implications of using the world's most popular sport, with an estimated 500 million regular participants,2 as a therapy. Relying on this scientific base with contributions from more than 250 authors from 22 countries, the scientific “Football is Medicine” platform has now been established. The first organizational meeting took place in Odense, Denmark, in January 2017, with 25 international researchers present and the first “Football is Medicine” conference was held in Lisbon, Portugal, in January 2018, with 50 speakers and a total of 300 delegates, with the Portuguese FA (FPF) as the main organizers and the University of Southern Denmark (SDU), The Danish FA (DBU) and UEFA as partners. It is a pleasure to confirm that the second Football is Medicine Conference will be held on January 25-26, 2019 in Odense, Denmark, with symposia on training in the evidence-based football concepts Football Fitness, FIT FIRST and 11 for Health on January 21-24, 2019, organized by SDU with DBU, FPF, and UEFA as partners. The purposes and possibilities of the global Football is Medicine platform are multifaceted, with research quality and productivity, scientific collaboration and networking, research dissemination as well as the development of an education in evidence-based football programs as the most prominent. The ongoing and future research into the effects of football training on human health is interesting and ambitious, with small-to-medium RCT projects on prevention and treatment of type 2 diabetes, cardiovascular disease, osteopenia, severe obesity and several types of cancer running or planned in Europe, South America, North America, Asia and Africa, and a large-scale multicentre project on Football Fitness in Europe. Pilot projects, feasibility studies, and small-scale RCT projects are also running for refugees and socially deprived groups as well as patient subsets with Parkinson's disease, dementia, psoriasis, asthma and anxiety, and it is being investigated whether Walking Football is a feasible and valid alternative to “running football” to achieve conspicuous health effects for patient groups.21 Long-term training studies and implementation projects are also being conducted with football for men with prostate cancer and Football Fitness for young, middle-aged and elderly women.19, 22 In all of these projects it is encouraged to take a multidisciplinary or interdisciplinary perspective and to integrate expertise and research questions from sports science, sport training physiology, sports medicine, sports psychology and sports sociology.2 The plans for global research dissemination and implementation are equally ambitious. With regard to research dissemination, there will be a focus on research articles and special issues in high-quality peer-reviewed international journals, like the present issue, with audio-visual coverage of the main results, including these, and with evidence-based popular articles, booklets and books published for the general population as well as healthcare workers and authorities. With regard to implementation there will be emphasis on global dissemination of evidence-based concepts with football training for children (FIT FIRST7, 8 and 11 for Health6, 8) and sedentary adults and patient groups (Football Fitness2-5, 9-22), but also evidence-based programmes using, for example, elite football clubs to promote healthy diet and everyday life physical activity for fans (FFIT23/EuroFIT24). For such large-scale implementation plans to succeed, a close collaboration is required between important stakeholders in the scientific community, the football governing bodies, the worldwide health organizations and national authorities. We look forward to contributing to this work. Fifteen years of research have produced strong evidence to show that football is indeed breath-taking, high-intensity, multipurpose training and is effective as physical and psycho-social therapy. In fact, football is medicine, and we are ready to act on this knowledge! The authors would like to thank the contributors in this present special issue and all the researchers that have contributed to the football for health work over the last 15 years. The authors would also like to thank Football Governing Bodies, Sports Confederations, Municipalities, Ministry Units, and Charities for their support and innovative collaboration, including the Danish FA, Faroese FA, and Portuguese FA, the Danish and Faroese Governments, Nordea-Fonden, TrygFonden, The Danish Heart Foundation, FIFA F-MARC, and UEFA. None declared.

In 2006, the recognised Nordic exercise physiologists Professors Pedersen and Saltin provided powerful evidence that exercise was an effective therapy in chronic disease—they emphasised exercise as a cornerstone in the prevention and non-pharmacological treatment of lifestyle diseases.1 Shortly after, American College of Sports Medicine (ACSM)’s president Dr Sallis delivered his well-documented and strong statement that ‘exercise is medicine and physicians need to prescribe it!’.2 These statements, and the research on which they are based, have influenced health authorities and governments around the globe to include exercise recommendations in the prevention and treatment of chronic diseases. Prominent worldwide exercise guidelines, including those from the WHO and ACSM, encourage sedentary individuals and patients to engage in exercise activities like brisk walking, jogging, cycling and fitness centre training. However, within physical activity guidelines, less emphasis has been placed on the health benefits of sporting activities.In a 2012 Lancet review, it was concluded that ‘sport may contribute to the health of nations’.3 A subsequent meta-analysis published in 2015 concluded that, in terms of health effects of sport, ‘the best evidence was found for football and running’, and that ‘evidence for health benefits of other sport disciplines was either inconclusive or tenuous’.4 Since then, high-quality research has emphasised the preventive effects of several ball games for sedentary adults, and we report that the evidence for the health benefits of football (soccer) is even stronger.5–10 More than 150 peer-reviewed articles published …

This article examines the development of social capital through the use and dynamics of different types of stories (“I,”“we” and “they”) as described by Robert D. Putnam. The data come from a research project in which inactive women participated in a 16‐week intervention program of physical exercise, either in the form of football or running. The study shows a positive development of social capital in the two different types of physical activity. The I‐stories show themselves to be central to bonding within the two groups and bridging outside the groups (developing and/or creating networks). The study also points to the importance of the activity itself for internal bonding illustrated through we‐ and they‐stories. Our data indicate that team sports, such as football, may have an advantage over individual sports in the development of social capital.

We examined whether improvements in the performance and health profile of an intensive 12-week football intervention could be maintained with a reduced training frequency. Seventeen healthy untrained males completed the study. Ten subjects trained 2.4 times/week for 12 weeks and another 52 weeks with 1.3 sessions/week [football group (FG)] and seven subjects acted as controls [control group (CG)]. For FG, fat mass (3.2 kg) and systolic blood pressure (8 mmHg) were lower (P < 0.05) after 64 than 0 weeks, and VO2max (8%) and Yo-Yo intermittent endurance level 2 test performance (49%) were higher (P < 0.05), with no difference between 64 and 12 weeks. After 64 weeks, quadriceps muscle mass (11%), mean fiber area (10%) and citrate synthase activity (18%) were higher (P < 0.05) than those at 0 weeks. Leg bone mass (3.5%) and density (2.0%) were higher (P < 0.05) after 64 than 0 weeks, but not different between 12 and 0 weeks. Plantar jump force (17-18%), 30-m sprinting velocity (1.3-3.0%) and muscle glycogen concentration (19-21%) were higher (P < 0.05) and blood lactate during submaximal exercise was lower (27-72%, P < 0.05) after 64 than after 12 and 0 weeks. The above-mentioned variables were unaltered for CG. In conclusion, positive adaptations in cardiovascular fitness obtained over 12 weeks of regular recreational football training can be maintained over a 1-year period with a reduced training frequency, with further development in musculo-skeletal fitness.

The present study investigated the performance effects and physiological adaptations over 16 weeks of recreational football training and continuous running for healthy untrained premenopausal women in comparison with an inactive control group [Football group (FG): n=21; running group (RG): n=18; CO: n=14]. Two weekly 1-h training sessions were performed in FG and RG. After 4 and 16 weeks of training VO(2max) was elevated (P < 0.05) by 7% and 15%, respectively, in FG, and by 6% and 10%, respectively, in RG. After 16 weeks, Yo-Yo intermittent endurance level 2 performance was 33% and 19% better (P < 0.05) for FG and 29% and 21% better (P < 0.05) for RG than after 4 and 0 weeks, respectively. Peak sprinting speed was 12% higher (21.0 +/- 0.6 vs 18.8 +/- 0.7 km/h; P < 0.05) for FG after the training period, whereas no difference was observed for RG. After 4 weeks citrate synthase (CS) and 3-hydroxyacyl-CoA dehydrogenase (HAD) activity was 9% and 8%, respectively, higher (P < 0.05) than before training in FG with no further changes during the last 12 weeks. In RG, CS increased (P < 0.05) by 12% after 4 weeks and no significant increase was observed for HAD. In FG, the number of capillaries per fiber was 18% higher (P < 0.05) after 16 weeks (2.44 +/- 0.15 vs 2.07 +/- 0.05 cap/fiber), with no significant difference for RG. No differences were observed between 0 and 16 weeks for CO. In conclusion, recreational women's football leads to significant increases in VO(2max), performance and muscular adaptations throughout a 16-week training period. Thus, football can be used as an activity to elevate the physical capacity of untrained women.

To examine the effects of regular participation in recreational soccer on health profile, 36 healthy untrained Danish men aged 20-43 years were randomised into a soccer group (SO; n = 13), a running group (RU; n = 12) and a control group (CO; n = 11). Training was performed for 1 h two or three times per week for 12 weeks; at an average heart rate of 82% (SEM 2%) and 82% (1%) of HR(max) for SO and RU, respectively. During the 12 week period, maximal oxygen uptake increased (p<0.05) by 13% (3%) and 8% (3%) in SO and RU, respectively. In SO, systolic and diastolic blood pressure were reduced (p<0.05) from 130 (2) to 122 (2) mm Hg and from 77 (2) to 72 (2) mm Hg, respectively, after 12 weeks, with similar decreases observed for RU. After the 12 weeks of training, fat mass was 3.0% (2.7 (0.6) kg) and 1.8% (1.8 (0.4) kg) lower (p<0.05) for SO and RU, respectively. Only SO had an increase in lean body mass (1.7 (0.4) kg, p<0.05), an increase in lower extremity bone mass (41 (8) g, p<0.05), a decrease in LDL-cholesterol (2.7 (0.2) to 2.3 (0.2) mmol/l; p<0.05) and an increase (p<0.05) in fat oxidation during running at 9.5 km/h. The number of capillaries per muscle fibre was 23% (4%) and 16% (7%) higher (p<0.05) in SO and RU, respectively, after 12 weeks. No changes in any of the measured variables were observed for CO. In conclusion, participation in regular recreational soccer training, organised as small-sided drills, has significant beneficial effects on health profile and physical capacity for untrained men, and in some aspects it is superior to frequent moderate-intensity running.