A literatura refere que os métodos convencionais de otimização do desempenho demonstram uma eficácia reduzida, pelo que estratégias alternativas devem ser consideradas (Gardner & Moore, 2006, 2012; Palmi, & Planas, 2018; Solé, Carraça, Serpa, & Palmi, 2014). O estudo do mindfulness e compaixão tem sido alvo de um crescente interesse no domínio da Psicologia. A prática que se tornou o foco da tradição budista há 2.600 anos, tornou-se parte da Psicologia contemporânea e da investigação, sobretudo na área da redução de stress realizados na década de 70. Mais recentemente, a abordagem focada na flexibilidade psicológica, considerada uma das abordagens de "terceira geração" nas intervenções cognitivo-comportamentais, foi incluída nessa abordagem. Embora os estudos ligados ao treino de competências psicológicas convencionais tenham mostrado resultados positivos, mas também inconsistentes no desempenho atlético, as intervenções baseadas no mindfulness (Gardner, 2016; Kaufman, Glass, & Pineau, 2018) emergiram recentemente como uma ferramenta potencialmente benéfica para melhorar o desempenho dos atletas de elite. Deste modo a combinação da prática de Redução de Stress Baseado no Mindfulness, (Kabat-Zinn, 2003) com as intervenções focadas na compaixão e flexibilidade psicológica oferecem alternativas, baseadas na evidência, que promovem a melhoria do desempenho desportivo, e a prevenção de lesões em alta competição (Birrer, Rothlin, & Morgan, 2012; Solé, Carraça, Serpa, & Palmi, 2014). Neste sentido, a presente tese de Doutoramento tem como objetivo principal adaptar e avaliar a eficácia de um Programa Baseado no Mindfulness em Jogadores de Futebol (MBSoccerP). Adicionalmente pretendeu-se estudar os atributos que estão envolvidos no desempenho de alta competição, especialmente nas modalidades coletivas, de forma a determinar se as estratégias baseadas no mindfulness, flexibilidade psicológica e auto compaixão promovem estados de desempenho ótimo, redução de sintomas psicopatológicos (ansiedade) e menor supressão do pensamento. Desta forma, realizaram-se os seguintes estudos: iv Estudo 1: Otimização da Performance em Atletas de Elite: As Intervenções Baseadas no Mindfulness. O objetivo desta revisão foi sintetizar os resultados empíricos que retratam a eficácia dos programas baseados no mindfulness na optimização da performance em atletas de elite. Para a realização deste estudo, efetuou-se uma pesquisa bibliográfica de artigos originais publicados entre 1985 e março de 2017, recorrendo às bases de dados Medline, Psych info, Web of Science, Cochrane, Ebscohost, Isi Web of Knowledge. A pesquisa focou-se nas intervenções baseadas no mindfulness, performance desportiva, atletas de elite e, por último, nas diferentes combinações de conceitos. Todos os artigos foram reunidos tendo em conta o design, tipo de controlo, população, instrumentos e resultados. No total, foram selecionados 26 artigos condicentes com os critérios metodológicos do presente estudo, verificando-se maioritariamente a implementação dos programas MSPE e MAC no campo da Psicologia da performance desportiva. Os resultados evidenciam que os programas MAC e MSPE são eficazes na otimização do desempenho desportivo de elite. Conclui-se que, os programas baseados no mindfulness são um fator importante na otimização da performance em alta competição. Estudo 2: Mindfulness and Compassion Strategies on Elite Soccer: Conceptualization of Mindfulness-Based Soccer Program (MBSoccerP) Com o objetivo de complementar o primeiro estudo, desenhou-se um programa baseado no Mindfulness (MBSoccerP) para otimizar o desempenho desportivo, tendo por base a evidencia científica existente nesta área no contexto desportivo. O programa MBSoccerP será descrito de forma exaustiva e detalhada no capitulo 3 da presente tese. A conceptualização metodológica do estudo foi realizada com base em publicações científicas das bases de dados PUBMED, MEDLINE, PsycINFO, Cochrane e ISI-Web of Science pesquisadas de 1985 a 2018 e com diferentes termos de pesquisa. Os resultados do estudo obtidos sugeriram a elaboração e implementação do programa MBSoccerP em atletas de futebol para testar a sua eficácia nos contributos intercorrentes (mindfluness, compaixão, flexibilidade psicológica) para melhorias integradas no desempenho desportivo. v Estudo 3: Programa baseado no Mindfulness para Futebol Profissional (MBSoccerP): estudo de eficácia em Atletas de Elite O objetivo deste estudo foi examinar a eficácia de um programa de mindfulness em atletas de futebol de elite - 2ª liga (MBSoccerP). Num plano quase-experimental com grupo de intervenção mindfulness (n = 28) e grupo de controlo (n = 29), foi testado o impacto do programa MBSoccerP e decorrentes relações e mecanismos de mudança. Os dados foram analisados recorrendo a t-student, correlações e a análises de covariância, para examinar possíveis efeitos e relações entre as variáveis antes e depois da intervenção MBSoccerP. Os resultados do estudo principal, a análise da covariância (medidas repetidas), indicaram que o grupo de intervenção (M = 25.68, SD = 3.42) melhorou significativamente nas subescalas Mindfulness_Agir Consciente, Mindfulness_ Não Reagir; nas subescalas Autocompaixão_Mindfulness, Autobondade e Condição Humana; na escala de Flow Disposicional, e no desempenho desportivo global dos atletas pela Ficha de Avaliação de Indicadores da Performance-Versões Atleta/Treinador. Verificou-se ainda a diminuição na subescala_ansiedade do Inventário Breve de Sintomas Psicopatológicos e na inflexibilidade psicológica, por comparação com o grupo de controlo. Os resultados sugerem que o MBSoccerP pode ser efetivo na otimização do desempenho, mindfulness, autocompaixão, flexibilidade psicológica e estado de flow. Estudo 4: Estudo piloto de um programa baseado no Mindfulness (MBSoccerP): O papel do mindfulness, autocompaixão e flexibilidade psicológica no estado de flow e desempenho desportivo em atletas de futebol de elite Neste estudo piloto procurou-se explorar os efeitos de um programa baseado no Mindfulness (MBSoccerP) numa amostra de 57 atletas profissionais de futebol. Testes t e correlações foram realizadas para examinar possíveis efeitos e relações entre as variáveis antes e depois da intervenção MBSoccerP. A regressão hierárquica também foi utilizada para avaliar a influência da flexibilidade psicológica, autocompaixão, e facetas de mindfulness nas medidas de desempenho desportivo e flow. Os resultados indicaram que as facetas mindfulness, a autocompaixão, a performance e o flow melhoraram do pré para a pós-teste, diminuindo o evitamento experiencial. Além disso, as facetas mindfulness foram preditoras de vi maior flow disposicional no pós-teste. A inflexibilidade psicológica foi preditor de um menor flow disposicional no pós-teste. Os resultados sugerem que o MBSoccerP pode ser eficaz na otimização do flow disposicional e desempenho desportivo. Estudo 5: O Treino Mindfulness e Compaixão no futebol profissional: efeitos, papéis e associações no flow, sintomas psicológicos e supressão de pensamento. O presente estudo explorou as relações entre autocompaixão, mindfulness, flexibilidade psicológica e índice de sintomas psicológicos (incluindo a ansiedade), supressão de pensamento e flow, através da implementação de treino mental focado no mindfulness, compaixão, e flexibilidade psicológica (MBPSoccerP) em atletas de futebol. Estudamos também a influência das facetas mindfulness, da flexibilidade psicológica, autocompaixão nas medidas de sofrimento psicológico, ansiedade, flow e supressão do pensamento. Num design quase experimental efetuou-se um estudo pré-pós teste, analisado com a estatística testes t emparelhados, correlações de Pearson e análise de regressão, realizadas numa amostra não clínica de jogadores de futebol - 2ª liga portuguesa (n = 57; M = 25,79 anos, DP = 3,3) Verificou-se que a autocompaixão, o mindfulness e a flexibilidade psicológica apresentaram uma associação negativa com o índice geral de sintomas psicológicos (incluindo ansiedade) e a supressão do pensamento, e uma associação positiva ao estado de flow disposicional. Estes resultados suportam que, a autocompaixão, o mindfulness e a flexibilidade psicológica explicaram a variação encontrada no índice geral de sintomas psicológicos (incluindo ansiedade), supressão de pensamentos e flow disposicional. Os resultados sugerem que as facetas mindfulness, a autocompaixão e o desenvolvimento da flexibilidade psicológica podem ser benéficos no cultivo de experiências desportivas mais positivas, mediando com maior frequência o estado de flow e diminuindo sofrimento psicológico e as preocupações ruminativas. Deste modo, e no seu cômpito geral, os resultados sugerem que o programa MBSoccerP pode ser efetivo na otimização do desempenho, nos traços mindfulness, na melhoria da autocompaixão, no aumento da flexibilidade psicológica e estado de flow. Contudo implicações práticas, assim como limitações e direções para futuras investigações são também enumeradas e debatidas nesta tese. Literature suggests that conventional methods of performance optimization demonstrate reduced effectiveness, so alternative strategies must be considered (Gardner & Moore, 2006; Neff & Germer, 2013; Mosewich, Crocker, & Kowalski, 2013; Palmi & Planas, 2018; Solé, Carraça, Serpa, & Palmi, 2014). However, psychology has increasingly become interested in the study and training of mindfulness and compassion. Mindfulness practice has deep roots in Buddhist tradition. More than 2,600 years ago, and in the late 1970s that mindfulness began to be studied by Psychology and reserach, specially, in stress reduction. More recently, So-called ’third wave’ cognitive and behavioural therapies represents a new generation of psychological therapies that are increasingly being used in the treatment of several difficulties and psychological problems and also foucus on the interplay of minfulness, compassion and psychological flexibility, namely the ACT Model. The importance of psychological skills training (PST) in the development of athletic performance is widely recognized. Therefore, Psychological skills are posited as effective for attaining optimal athletic performance, and the benefit of PST is widely reported. Although considerable scientific evidence is available regarding the efficacy of traditional psychological performanceenhancement methods, some authors claim that sport psychology interventions have not been critically examined, and most studies investigating the efficacy of PST do not meet the criteria for evidencebased empirical support. Hence, Recently, interest in mindfulness-based interventions has increased in sport psychology as a way to improve the performance of elite athletes (Gardner, 2016; Kabat-Zinn, 2003; Kaufman, Glass, & Pineau, 2018) Therefore the combination of MBSR practice (Kabat-Zinn, 2003) with interventions focused on compassion and psychological flexibility, offer evidence-based alternatives that promote performance improved and sport injuries prevention in high performance context (Birrer, Rothlin, & Morgan, 2012; Solé, Carraça, Serpa, & Palmi, 2014; Gardner, 2016, Kaufman, Glass, & Pineau, 2018; Moghadam, 2013; Mosewich, Crocker, & Kowalski, 2013). viii Hence, this Ph.D. thesis shows as main objective to adapt and evaluate the effectiveness of a mindfulness based program (MBSoccerP) in sport context. Additionally, it was intended to study the attributes that are involved in the performance of high competition, especially in team sports, in order to understand if strategies based on mindfulness, psychological flexibility and compassion promote optimal performance states, reduction of psychopathological symptoms (anxiety) and though suppression. Hence, a first literature review was conducted with the purpose of synthesizing the empirical results that portray the effectiveness of mindfulness-based programs in performance optimization in elite athletes. 1st study: Enhance Sport Performance of Elite Athletes: The Mindfulness-Based Interventions The purpose of this review is to summarize the empirical findings on the effectiveness of mindfulness-based programs to enhance elite athletes sport performance. The search included original articles published from 1985 to March 2017, using Medline, Psych info, Web of Science, Cochrane, Ebscohost, Isi Web of Knowledge databases and references of retrieved articles.The main search terms were mindfulness programs, sport performance, elite athletes, in different combinations as needed. All articles were coded for their design, type of control, study population, and outcome measures. Search returned 26 articles, and set out 2 mainmindfulness-based interventions on the field of elite sport performance. Despite methodological limitations in theresearch design, the results show MAC and MSPE programs as effective on enhancing elite athlete’s sportsperformance. To confirm these preliminary results, further research, with improved experimental designs, isrecommended. Findings yielded mindfulness programs as an important factor on elite sport performance. In a second moment, another initial study (study 2) was developed, with the objective of developing the sessions, implement and determine the effectiveness of the implementation of the Mindfulness-based program (MBSoccerP) to optimize the sport performance, based on mindfulness evidence based programs developed in sport context. “Mindful Sport Performance Enhancement” (MSPE, Kaufman, Glass, & Pineau, 2018); “Applying Selfix Compassion in Sport” (Gilbert, 2009; Mosewich, Crocker, Kowalski, & DeLongis, 2013; Tirch, 2010); “Mindful Athlete” (Mumford, 2015); “Mindfulness-Acceptance-Commitment Appraoch” (MAC, Gardner, & Moore, 2007, 2012); Mindfulness-Based Stress Reduction ( MBSR, Kabat-Zinn, 1985, 2003). The MBSoccerP program will be described in detail in chapter 3 of the present thesis. Study 2: Mindfulness and Compassion Strategies on Elite Soccer: Conceptualization of Mindfulness-Based Soccer Program (MBSoccerP) The difference between success and failure has become increasingly smaller in sport. A “third wave” approach in sport psychology has been used recently to increase the performance level of the elite athletes with very well-defined programs. (Birrer, 2012, Gardner, & Moore, 2007; Gross et al., 2016). Study findings yielded that high-level athlete’s meta-awareness and effective refocusing training by mindfulness-based programs were identified as important factors on performance training and competition (Carraça, Serpa, Palmi, & Rosado, 2018). Explore the conceptualization and implementation of the Mindfulness-Based Soccer Program (MBSoccerP) to optimize mindfulness, compassion in the elite soccer performance. Secondary aims are: understand the relationship between attributes of mindfulness traits and self-compassion - the impact on the state of sports performance and dispositional flow; the relation between psychological symptoms, experiential avoidance and consequent effect on the level of anxiety and sports performance. Letter to editor was conduct based on scientific publications and was retrieved from the PUBMED, MEDLINE, PsycINFO, Cochrane, ISI-Web of Science databases searched from 1985 to 2018. The main references cited in reviews were also included in the review to ensure that no relevant studies were excluded. The main search terms were mindfulness-based interventions, sport performance, soccer, flow state, self-compassion, in different combinations as needed. The letter to editor allowed documenting advantages in participating in the Mindfulness- Based Soccer Program MBSoccerP with increase the attributes related to mindfulness, higher levels of self-compassion, acceptance flow state, sport performance, a lower overall index of psychopathological symptoms and physiological response to stress, less suppression of thoughts. Study findings yielded could suggest that MBSoccerP can be helpful to enhance x performance in sport. Thus, in a third phase, the main goal of this thesis was to adapt and evaluate the effectiveness of a Mindfulness-Based Program in Football Players (MBSoccerP). Study 3: The Mindfulness- Based Soccer Program (MBSoccerP): Effects on Elite Athletes Newly, 3º wave Cognitive Behavioral Therapy (CBT) programs suggest that mindfulness-based programs might be a powerful strategy to optimize performance and improve flow. The aim of this study was to examine the effectiveness of a Mindfulness-Based Soccer Program (MBSoccerP) on elite soccer athletes. In a quasi-experimental design with experimental (n = 28) and control group (n = 29), the effectiveness of MBSoccerP was tested. The results of an analysis of covariance with repeated measures indicate that the intervention group (M=25.68, SD=3.42) significantly improved in Mindfulness-act with awareness; Mindfulness non-react; Self-compassion mindfulness; Selfcompassion self-kindness; Selfcompassion common-humanity subscales; Dispositional flow state total scale; and decreased Brief Symptom Inventory anxiety subscale and experiential avoidance, as traits compared to the control group, and increase direct measures scores of sports performance Athlete´s Performance Self-Rating Scale and Coach´s Performance Self-Rating Scale. Results suggest that MBSoccerP can be effective in enhance elite soccer performance, self-compassion, psychological flexibility, mindfulness and flow. Additionally, it was intended to study the attributes that are involved in the performance of high competition, especially in collective modalities, in order to determine if strategies based on mindfulness, psychological flexibility and compassion promote optimal performance states. The multiple hierarchical regressions were thus used to evaluate the influence of the main constructs of the MBSoccerP program, described in study 4 and study 5. Study 4: A Pilot study of a Mindfulness- Based Program (MBSOCCERP): The Potential Role of Mindfulness, Self-Compassion and Psychological flexibility on flow and Elite Performance in Soccer Athletes. xi Mindfulness-based interventions have consistently demonstrated associations with multiple aspects of flow and sport performance. In this current pilot study, we sought to explore the effects of Mindfulness-based program for elite soccer athletes (MBSoccerP) training on self-compassion, mindfulness, and psychological flexibility, flow and sport performance outcomes on a sample of 57 elite soccer players (Portuguese 2ª league) from two different cohorts participated in this study. Also, we examined the relationship between mindfulness, psychological flexibility, and self-compassion at baseline-predicted flow and performance measures. Paired t-tests and correlations were conducted to examine changes and significant relation between variables before and after the MBSoccerP intervention. Also hierarchical regression was used to assess the influence of baseline psychological flexibility, self-compassion, and mindfulness facets on flow and sport performance measures at postintervention in this pre-/post-pilot study. Results suggested that mindfulness, self-compassion, direct forms of performance and flow improved from pre to post-intervention and psychological inflexibility decreased. Further, mindfulness predicted higher flow at post intervention while controlling for baseline mindfulness. Psychological inflexibility predicted lower dispositional flow at post intervention. Findings suggest that MBSoccerP may be effective for improving flow and performance. Study 5: Mindful Compassion Training on Elite Soccer: Effects, Roles and Associations on Flow, Psychological Distress and Thought Suppression. Research on mindfulness and self-compassion has suggested that these closely related constructs are also strongly related to flow, psychological distress, experiential avoidance and thought suppression. Despite the potential of this approach, literature in respect to the relation and role of these constructs in the sport context is scarce, particularly in soccer. The current study explored relations among self-compassion, mindfulness, psychological flexibility, and psychological distress (including anxiety), thought suppression and flow state, through the implementation of Mindfulness-Based Soccer Program (MBPSoccerP) for elite athletes. This study also analyzed the influence of baseline psychological flexibility, self-compassion and mindfulness facets on psychological distress, anxiety, flow and thought suppression measures at post-intervention. Methods: A quasiexperimental design was used and involved a pre-/post-pilot study and paired t-tests, pearson correlations and hieraquical regression analyses were conducted to determine the common xii and unique variance in sport context predicted by these constructs and to compare their relative predictive strength in a nonclinical sample of elite soccer players -Portuguese 2º league (n=57; Mage = 25.79 years, SD = 3.3) Results: Findings showed self-compassion, mindfulness and psychological flexibility were negative associated with psychological distress (including anxiety) and thought suppression; and positively related to flow. In support, self-compassion, mindfulness and experiential avoidance explained variance beyond psychological distress (including anxiety), thought suppression and flow. Conclusions: Results suggest that mindfulness, self-compassion and psychological flexibility development may be beneficial in cultivating positive sport experience and flow state and less psychological distress and thought suppression. Overall the results suggest that the MBSoccerP program can be effective in optimizing performance, and increasing mindfulness traits, self-compassion, psychological flexibility and flow state. The results suggest that mindfulness, self-compassion, and the development of psychological flexibility can be beneficial in cultivating more positive sport experiences, and more often mediating flow and reducing psychological distress and negative thought. It is concluded that, programs based on mindfulness, are an important factor in the optimization of performance in high competition. The aim of this thesis is to explore the origins and applications of psychological skills training programs based on mindfulness, selfcompassion and psychological flexibility in the context of elite soccer, in order to meet the aims and research questions of the main study and sub studies. Implications for practice, limitations and some of the directions for future research are also stated.