Effects of Recreational Soccer on Health Outcomes: A Narrative Review
Soccer is a very popular team sport that involves a variety of physical actions, such as sprints, accelerations, sudden decelerations, and jumps, among others. Research has placed recreational soccer in a good position as a strategy to increase physical activity levels and promote health across the lifespan. In this regard, recreational (non-competitive) soccer promotes social interaction and has the potential to increase long-term adherence to physical activity, even in those without prior experience in this sport. In this narrative review, we address the effects of recreational soccer on various health outcomes across the lifespan (i.e., from childhood to the elderly years) in both sexes. In addition, the beneficial effects of recreational soccer for people with prevalent pathologies, such as hypertension, type II diabetes mellitus, and cancer, are discussed.
KeywordsPhysical fitness Physical activity Hypertension Diabetes Cancer Football
Soccer is a very popular team sport with more than 400 million active federated players around the world and with a great potential as a health promotion strategy for inactive and sedentary people [38, 40]. Most studies that have analyzed the effect of physical exercise on health, have traditionally focused on walking, running or cycling at intensities between 30% and 90% of the maximum oxygen consumption (VO2max) . However, few studies have analyzed the effects of a team sport such as soccer, in which frequent changes in intensity occur, on different health outcomes .
Soccer is characterised by a variety of physical actions including sprints, accelerations, sudden decelerations, jumps of maximum intensity and rapid and powerful kicks, among others. This combination of skills seems to improve cardiorespiratory and musculoskeletal physical fitness and therefore, decrease the risk of suffering from prevalent diseases . The very nature of soccer places it as a high-intensity interval training exercise that has received a lot of attention in the last years due to its potential health benefits.
Within the context of sport and health, it is important to distinguish between competitive (especially elite) and recreational sport, because their characteristics and potential effects are different. The present narrative review focuses on recreational soccer, exclusively. Recreational soccer can be defined as the practice of soccer without the existence of a competitive objective within the framework of a federated competition or a license for its practice, encompassing only the practice of soccer in a free form and with recreational or health purposes.
Several intervention studies have been carried out in order to evaluate the effect of recreational soccer on various health outcomes in different populations, such as children and adolescents [15, 19, 27, 41, 46, 53, 54, 55, 56], adults [1, 7, 8, 9, 10, 11, 20, 24, 32, 33, 37, 41], elderly [4, 5, 17, 41, 45], premenopausal women [16, 26, 28], hypertensive [2, 3, 22, 30, 34], type II diabetics [14, 44], people in unfavourable social situations ("homeless") , and as an adjunct to treatment in cancer patients and cancer survivors [12, 13, 49, 50, 51, 52]. Importantly, recreational soccer also promotes social interaction, the creation of social capital and links between the people involved. It also seems to have the potential to promote long-term adherence to physical activity, even for men and women with no prior experience in this sport .
The number and diversity of studies focused on examining the potential benefits of recreational soccer is high, and therefore, a review and synthesis of the available evidence is required. This narrative review brings together previous reviews [7, 23, 25, 29], as well as original articles published later in both sexes. Therefore, the aim of this review is to study the beneficial effects of recreational soccer on health outcomes in untrained people of different ages, sex and socioeconomic status. This review also aims to compile the existing evidence about the beneficial effects of recreational soccer in people suffering from prevalent pathologies, such as hypertension, type II diabetes mellitus and cancer.
Soccer, Health and Men
Summary of soccer-related studies, main outcome variables and main findings in healthy populations of different ages, sex and socioeconomic status
Main outcome variables
Weight, fat-free mass, % body fat, BMC, BMD, bone area, bone geometry, bone stiffness, osteocalcin, leptin, balance, blood pressure, resting heart rate, systolic function, diastolic function, cardiac structure, peripheral arterial function
Improvements in: bone mineral content, body composition, cardiac structure and function
VO2max, capillary density, reflex response, osteocalcin, BMC, BMD, PINP, CTX-1, muscular pain, perceived exertion, muscle mass, muscle strength, HDL cholesterol, LDL cholesterol, triglycerides, blood pressure, BMI, % body fat, heart rate, diastolic function, cardiac structure
Improvements in: cardiorespiratory health, musculoskeletal health (through osteogenesis), muscular adaptations, falls and fractures, sensory-motor function
Cardiac structure, systolic function, diastolic function, blood pressure, VO2max, P1NP, CTX-1, osteocalcin, BMD, BMI, muscle mass, % body fat, capillary density, HDL cholesterol, LDL cholesterol, HbA1c, plasma glucose, plasma insulin, muscle strength
Improvements in: cardiovascular health, osteogenesis, physical function and body composition
In youth, soccer training has been proven to be an effective method to improve performance in intermittent exercise, and improve coordination and VO2max . In obese children, regular participation in a soccer program is at least as effective as a physical exercise program for improving fitness, health and self-esteem outcomes . In addition, cross-sectional and longitudinal studies in male adolescent athletes (12–14 years old) have shown soccer to be a much more osteogenic sport compared with swimming and cycling at regions of clinical relevance, such as the hip and femoral neck [54, 55, 56]. These are key findings that soccer maximizing peak bone mass during growth reduces the risk of osteopenia and/or osteoporosis later in life .
The potential benefits of recreational soccer are also evident in unfavourable socio-economic circumstances as shown by the findings from the intervention carried out by Randers et al.  in adults (37 ± 10 years). The authors implemented a recreational soccer program to homeless people and found that 12 weeks of training, 3 times a week, improved participants’ VO2max (from 36.7 to 40.6 mL/min/kg), reduced their body fat by 1.6 kg and LDL cholesterol by 6%. In addition, their resistance and capacity to carry out intermittent exercises significantly improved, causing a marked impact on the cardiovascular health of this disadvantaged group in need of clinical care.
One of the reasons behind the positive findings in such diverse populations, may be the level of intensity reached as indicated by the elevated heart rate responses recorded, which can be achieved by just varying the number of players and/or the pitch size during the games . These games, usually called small-sided games (4 vs. 4, 5 vs. 5, 6 vs. 6, 7 vs. 7), seem to have the potential to create physiological adaptations and improve performance following regular training . In addition, factors such as the number of players or the size of the playing area may vary the cardiovascular demand, which is increased when the game takes place with fewer players. Therefore, the number of players stands as a primary factor when controlling the intensity of tasks and training in soccer .
Although the health benefits of recreational soccer practice are numerous as shown in this narrative review, it is important to mention that, as in any sport, there is a risk of injury. According to data from a study conducted in Spanish amateur soccer players, the frequency of getting injured is 0.11 per player per year, or 1 out of 10 players suffer an injury every year . In professional soccer players from the Spanish First Division, the overall incidence of injuries is 5.6 per 1000 h of exposure, and the incidence is significantly higher during competition and training (43.5 vs. 3.5 per 1000 h of exposure, respectively) , a pattern that is also observed in players from the Spanish Second Division . Both in recreational and professional soccer, injuries of lower extremity, especially of thigh, knees and ankles, predominate.
Soccer, Health and Women
Women's soccer is one of the fastest growing sport activities. In fact, there has been a 50% increase in the number of players worldwide during the last 8 years . In recent years, the interest on the health effects of recreational soccer in untrained women have substantially grown [1, 8, 16, 28]. Randers et al.  compared the cardiovascular health profiles of three groups: a group of 27 elite soccer players (24.4 ± 4.0 years), a group of 8 untrained women (27.0 ± 6.5 years) who participated in a recreational soccer program during 16-week, and a control group of 28 untrained women (29.3 ± 5.7 years) who did not perform any intervention. The results showed that elite players had a better cardiovascular health profile, higher VO2max, lower percentage of body fat and better cardiac function than the control group. Interestingly, the results also showed that the cardiovascular health profile of the untrained women involved in the 16-week program significantly improved with respect to the control group, although no differences were observed in comparison with the elite players.
Jackman et al.  found in their study with 8 untrained women (27.0 ± 6.5 years, VO2max 33.8 ± 5.7 mL/min/kg) that took participation in a 16-week recreational soccer program produced positive adaptations in the musculoskeletal health profile, including an increase in lean mass, reduction in fat mass, improved postural balance and increased osteocalcin concentrations. Pedersen et al.  emphasized that recreational soccer for women (19–45 years old), as opposed to continuous running, was effective in improving the response to sudden overloads on the trunk, suggesting that soccer training has the potential to lower the risk of lower back injury, a well-known clinical and social issue nowadays.
In later stages of menopause, muscle dysfunction and reduced bone mineral density could predispose to the development of osteoporosis and sarcopenia later in life. Therefore, maintaining an active lifestyle during the pre-menopausal stage may preserve bone mass and delay the onset of osteoporosis and sarcopenia . So far, some studies have been carried out for examining the effect of participating in recreational soccer in untrained pre-menopausal women. Krustrup et al.  compared the benefits of two intervention programs on health outcomes in untrained pre-menopausal women (36 ± 2 years); with a 16-week soccer training period vs. moderate intensity continuous running. After the 16-week intervention period, the soccer group decreased their blood pressure, fat mass and resting heart rate, while improvements in VO2max, lipid profile, muscle capillarization and arterial stiffness were found. Moreover, improvements in the systolic and diastolic function of the left ventricle were found, suggesting that the cardiac adaptations seem to be more consistent through participation in soccer than continuous running .
Similarly, Krustrup et al.  examined the long-term effects (16 months, two 1-h sessions per week) of recreational soccer training (40 ± 3 years) and continuous running (40 ± 2 years) in pre-menopausal women in comparison with a control group (38 ± 4 years). Specifically, the authors examined musculoskeletal and cardiac adaptations and reported a 24% increase in the left ventricular diameter after diastole in the soccer group, only a 5% increase in the continuous running group and no adaptations in the control group. Muscular function, reflex response, balance and bone mineral density improved in both intervention groups, but more significantly in the soccer group. In addition, the size of the cardiac chambers increased, as well as the left ventricular function (systolic and diastolic) and the right ventricular function (systolic).
Soccer and Prevalent Diseases
Summary of soccer-related studies, main outcome variables and main findings in unhealthy populations
Main outcome variables
Blood pressure, resting heart rate, heart rate variability, VO2max, HDL cholesterol, LDL cholesterol total cholesterol, triglycerides, % body fat, peripheral arterial function, plasma glucose, plasma insulin, BMC, BMD, fat-free mass, cardiac structure, systolic function, diastolic function
Improvements in: cardiovascular profile (through blood pressure), metabolic profile, physical fitness (e.g. aerobic) and body composition
VO2max, BMD, fat-free mass, BMI, waist circumference, plasma glucose, HbA1c, HDL cholesterol, LDL cholesterol, total cholesterol, triglycerides, plasma insulin, insulin resistance, cardiac structure, systolic function, diastolic function
Improvements in: cardiovascular profile (through triglycerides, blood pressure, VO2max, cardiac function and insulin sensitivity)
BMI, % body fat, BMC, BMD, fat-free mass, muscle strength, CTX-1, osteocalcin, P1NP, balance, VO2max
Improvements in: physical function and body composition (through muscle mass, muscle strength, and bone mass)
High blood pressure is associated with an increased risk for all-cause mortality, cardiovascular mortality and the likelihood of suffering from stroke, coronary heart disease, atrial fibrillation and renal failure .
Currently, there is strong scientific evidence of the influence that aerobic activities have on reducing blood pressure. In addition, the practice of an intermittent sport such as recreational soccer has been associated with lower blood pressure . In this regard, Krustrup et al.  managed to reduce blood pressure levels in a group of adults with moderate hypertension, with two 1-h soccer training sessions weekly over 6 months. The systolic and diastolic blood pressure decreased from 151 ± 10 to 139 ± 10 mmHg and from 92 ± 7 to 84 ± 6 mmHg, respectively. However, the reduction was lower in a group that was asked to follow the physical activity guidelines for adults , lowering the systolic blood pressure from 153 ± 8 to 145 ± 8 mmHg and the diastolic blood pressure from 96 ± 6 to 93 ± 6 mmHg. Similar results were found in the study by Andersen et al. , with two intervention groups, one of them receiving recreational soccer training and the other one following the traditional medical physical activity recommendations. After 3 months, the soccer group had the systolic and diastolic blood pressure reduced by 12 ± 3 and 7 ± 1 mmHg, respectively, while no significant changes were observed in the group receiving the physical activity recommendations. In addition, parameters such as resting heart rate, VO2max and body fat improved to a greater extent in the soccer group with respect to the physical activity recommendations group. Knoepfli-Lenzin et al.  compared the effect of 12-week soccer practice or continuous running on blood pressure. Both groups performed the same training volume, 1 h per week, 2.4 sessions per week and managed to reduce blood pressure. However, this reduction was significantly greater in the soccer group than the continuous running group (− 9 ± 5 mmHg vs. − 4 ± 6 mmHg).
Despite the studies conducted in this field are recent, the findings support the potential of recreational football as a non-pharmacological complement for the treatment of mild and moderate hypertension in middle-aged men, without previous experience in this sport . In this line, recreational soccer seems to have positive effects on various parameters of arterial health, such as a marked reduction in systolic and diastolic blood pressure, as well as a lower resting heart rate, lower body fat content, higher levels of VO2max and healthier lipid profile .
Type II Diabetes
The prevalence of type II diabetes in adults worldwide is estimated to rise to 5.4% . Physical exercise, due to its effectiveness in the control of the disease and few adverse effects , has been considered as one of the main pillars for diabetes’ treatment, along with diet and medication. Specifically, type II diabetes stands as a global health issue linked with obesity and a sedentary lifestyle and, increases the risk of mortality and morbidity . In this context, Schmidt et al.  examined the effectiveness of a 24-week recreational soccer program (two 1-h sessions weekly) on various health outcomes in type II diabetic adults (50 years old). The findings showed that the soccer group improved cardiac structure and function, the capacity to perform physical exercise and cope with intermittent efforts, VO2max and blood pressure levels, compared to the control group. This study was the first to report an improved myocardial systolic function after a physical exercise program in patients with type II diabetes. These findings are of relevance since improvements in the cardiorespiratory system may reduce morbidity and mortality rates in this population. In addition, findings from an intervention study carried out in men and women between the ages of 48 and 68, showed soccer participation (40 min, 3 times a week for 12 weeks) together with diet program to be more effective in improving insulin sensitivity, VO2max and lipids profile than just undergoing a diet program .
There seems to be a consensus in the key role of physical activity to improve physical capacity and quality of life in cancer patients . Prostate cancer, the most frequent among men, is known to increase the risk of cardiovascular disease, diabetes and osteoporosis . In addition, prostate cancer is associated with adverse effects caused by androgen deprivation treatment, such as rapid loss of bone mass, decreased performance and physical function, and increased risk of fractures . Several studies using recreational soccer interventions in patients with prostate cancer have been published [12, 13, 49, 50, 51, 52], and findings show improvements in body composition (i.e., increase in muscle mass and bone mineral density and decrease in adipose tissue), muscle strength, physical function, and quality of life.
In the study published by Uth et al. , patients (67.1 ± 7.1 years) under treatment for prostate cancer were assigned either to a soccer group (2–3 times per week, 45–60 min, during 32 weeks) or a control group (no intervention). The main findings showed the soccer group improved bone mineral density of the hip and femoral neck, and physical function during activities such as climbing stairs or jumps, in comparison with control group. In addition, improvements in the strength of the knee extensors and total lean mass were also observed in this soccer group .
It is important to underline that soccer has other benefits, such as those from a social and personal perspective. Soccer acts as a link among patients making them able to approach other patients with their same condition, with whom they share their intimacy and experiences related to the pathology and its treatment .
To sum up, the evidence regarding the effects of recreational soccer on health outcomes in people with prevalent diseases suggest that soccer practice can be a real form in the treatment of hypertension, but not for that of type II diabetes and cancer. While the benefits in hypertension relate to lowering blood pressure, for type II diabetes and cancer relate to general well-being and health risk. Of note, different pitch sizes imply different physiologic demands; however, since this information was not available in a number of the manuscripts used for this narrative review, we cannot draw conclusions at this respect.
Football stands as a form of physical exercise with important clinical implications for people with different socioeconomic status and physical fitness. The present narrative review describes how the practice of recreational soccer is associated with a series of physiological stimuli capable of improving numerous parameters related to cardiovascular, metabolic and musculoskeletal health, as well as psychological and social dimensions. Finally, the review describes the clinical utility of recreational soccer in health outcomes in people suffering from prevalent pathologies such as hypertension, type II diabetes and cancer.
All authors have substantially contributed in writing and critically reviewing the manuscript.
F.B.O. Research activity is supported by the Spanish Ministry of Economy and Competitiveness—MINECO/FEDER (DEP2016-79512-R); the University of Granada, Plan Propio de Investigación 2016, Excellence actions: Units of Excellence, Unit of Excellence on Exercise and Health (UCEES); the European Union's Horizon 2020 research and innovation programme under grant agreement No 667302; the SAMID III network, RETICS, funded by the PN I + D + I 2017–2021 (Spain), L.G.M. is funded by Programa de Captación de Talento—UGR Fellows, from the University of Granada, Spain. J.M.G. is supported by the Spanish Ministry of Education, Culture and Sport (FPU14/06837).
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