The Impact of a Psychological Skills Training and Mindfulness-Based Intervention on the Mental Toughness, Competitive Anxiety, and Coping Skills of Futsal Players—A Longitudinal Convergent Mixed-Methods Design
Abstract
:1. Introduction
2. Materials and Methods
2.1. Participants
2.2. Design
2.3. Data Collection
2.4. Procedure
2.4.1. Ten-Session PSTMI
2.4.2. Qualitative Interviews
2.5. Data Analysis
2.6. Ethical Information
3. Results
3.1. Quantitative Analysis
3.1.1. Changes in Pre- and Post-Intervention Outcome Measures
3.1.2. Years of Experience Predicting Difference in Post-Intervention Outcome Measures
3.2. Reflexive Thematic Analysis
3.2.1. Theme 1: Post-Intervention Enhancement in Athletic Performance and Mental Wellbeing
3.2.2. Theme 2: The Impact of Years of Experience on Skill Learning
3.2.3. Theme 3: Instilling Social Identity through Sport Psychology Sessions
3.2.4. Theme 4: Diverse Views on how to Improve the Intervention
3.2.5. Theme 5: The Non-Athletic Commitments of Futsal Players
3.3. Integrating Quantitative and Qualitative Data
4. Discussion
4.1. The Impact of the Intervention on Mental Health Variables
4.2. The Impact of Level of Experience on Mental Health Variables
4.3. Strengths and Limitations
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
- Röthlin, P.; Birrer, D.; Horvath, S.; Holtforth, M.G. Psychological skills training and a mindfulness-based intervention to enhance functional athletic performance: Design of a randomized controlled trial using ambulatory assessment. BMC Psychol. 2016, 4, 1–11. [Google Scholar] [CrossRef]
- Fossati, C.; Torre, G.; Vasta, S.; Giombini, A.; Quaranta, F.; Papalia, R.; Pigozzi, F. Physical exercise and mental health: The routes of a reciprocal relation. Int. J. Environ. Res. Public Health 2021, 18, 12364. [Google Scholar] [CrossRef]
- Jewett, R.; Sabiston, C.M.; Brunet, J.; O’Loughlin, E.K.; Scarapicchia, T.; O’Loughlin, J. School sport participation during adolescence and mental health in early adulthood. J. Adolesc. Health 2014, 55, 640–644. [Google Scholar] [CrossRef]
- Galper, D.I.; Trivedi, M.H.; Barlow, C.E.; Dunn, A.L.; Kampert, J.B. Inverse association between physical inactivity and mental health in men and women. Med. Sci. Sports Exerc. 2006, 38, 173–178. [Google Scholar] [CrossRef]
- Morgan, W.P. Selected psychological factors limiting performance: A mental health model. In Limits of Human Performance; Clarke, D.H., Eckert, H.M., Eds.; Human Kinetics: Champaign, IL, USA, 1985; pp. 70–80. [Google Scholar]
- Renger, R. A review of the profile of mood states (POMS) in the prediction of athletic success. J. Appl. Sport Psychol. 1993, 5, 78–84. [Google Scholar] [CrossRef]
- Raglin, J.S. Psychological factors in sport performance: The mental health model revisited. Sports Med. 2001, 31, 875–890. [Google Scholar] [CrossRef]
- Vealey, R.S. Sport personology: A paradigmatic and methodological analysis. J. Sport Exerc. Psychol. 1989, 11, 216–235. [Google Scholar] [CrossRef]
- Rowley, A.J.; Landers, D.M.; Kyllo, L.B.; Etnier, J.L. Does the iceberg profile discriminate between successful and less successful athletes? A meta-analysis. J. Sport Exerc. Psychol. 1995, 17, 185–199. [Google Scholar] [CrossRef]
- Purcell, R.; Gwyther, K.; Rice, S.M. Mental health in elite athletes: Increased awareness requires an early intervention framework to respond to athlete needs. Sports Med. Open 2019, 5, 46. [Google Scholar] [CrossRef]
- Hardy, L.; Jones, G.; Gould, D. Understanding Psychological Preparation for Sport: Theory and Practice of Elite Performers; Wiley: Hoboken, NJ, USA, 2018. [Google Scholar]
- Keng, S.-L.; Smoski, M.J.; Robins, C.J. Effects of mindfulness on psychological health: A review of empirical studies. Clin. Psychol. Rev. 2011, 31, 1041–1056. [Google Scholar] [CrossRef]
- Lochbaum, M.; Stoner, E.; Hefner, T.; Cooper, S.; Lane, A.M.; Terry, P.C. Sport psychology and performance meta-analyses: A systematic review of the literature. PLoS ONE 2022, 17, e0263408. [Google Scholar] [CrossRef]
- Wu, C.-H.; Nien, J.-T.; Lin, C.-Y.; Nien, Y.-H.; Kuan, G.; Wu, T.-Y.; Ren, F.-F.; Chang, Y.-K. Relationship between mindfulness, psychological skills, and mental toughness in college athletes. Int. J. Environ. Res. Public Health 2021, 18, 6802. [Google Scholar] [CrossRef]
- Walter, N.; Nikoleizig, L.; Alfermann, D. Effects of self-talk training on competitive anxiety, self-efficacy, volitional skills, and performance: An intervention study with junior sub-elite athletes. Sports 2019, 7, 148. [Google Scholar] [CrossRef]
- Josefsson, T.; Ivarsson, A.; Lindwall, M.; Gustafsson, H.; Stenling, A.; Böröy, J.; Mattsson, E.; Carnebratt, J.; Sevholt, S.; Falkevik, E. Mindfulness mechanisms in sports: Mediating effects of rumination and emotion regulation on sport-specific coping. Mindfulness 2017, 8, 1354–1363. [Google Scholar] [CrossRef]
- Zandi, H.; Amirinejhad, A.; Azizifar, A.; Aibod, S.; Veisani, Y.; Mohamadian, F. The effectiveness of mindfulness training on coping with stress, exam anxiety, and happiness to promote health. J. Educ. Health Promot. 2021, 10, 177. [Google Scholar]
- Rice, S.M.; Gwyther, K.; Santesteban-Echarri, O.; Baron, D.; Gorczynski, P.; Gouttebarge, V.; Reardon, C.L.; Hitchcock, M.E.; Hainline, B.; Purcell, R. Determinants of anxiety in elite athletes: A systematic review and meta-analysis. Br. J. Sports Med. 2019, 53, 722–730. [Google Scholar] [CrossRef]
- Mottaghi, M.; Atarodi, A.; Rohani, Z. The relationship between coaches’ and athletes’ competitive anxiety, and their performance. Iran. J. Psychiatry Behav. Sci. 2013, 7, 68. [Google Scholar]
- Spyrou, K.; Freitas, T.T.; Marín-Cascales, E.; Alcaraz, P.E. Physical and physiological match-play demands and player characteristics in futsal: A systematic review. Front. Psychol. 2020, 11, 569897. [Google Scholar] [CrossRef]
- Yiannaki, C.; Barron, D.; Collins, D.; Carling, C. Match performance in a reference futsal team during an international tournament–implications for talent development in soccer. Biol. Sport 2020, 37, 147–156. [Google Scholar] [CrossRef]
- Yeemin, W.; Dias, C.S.; Fonseca, A.M. A systematic review of psychological studies applied to futsal. J. Hum. Kinet. 2016, 50, 247–257. [Google Scholar] [CrossRef]
- Kesmodel, U.S. Cross-sectional studies-what are they good for? Acta Obstet. Gynecol. Scand. 2018, 97, 388–393. [Google Scholar] [CrossRef] [PubMed]
- Naser, N.; Ali, A.; Macadam, P. Physical and physiological demands of futsal. J. Exerc. Sci. Fit. 2017, 15, 76–80. [Google Scholar] [CrossRef] [PubMed]
- Cavichiolli, F.R.; Cheluchinhak, A.B.; Capraro, A.M.; Marchi Junior, W.; Mezzadri, F.M. O processo de formação do atleta de futsal e futebol: Análise etnográfica. Rev. Bras. De Educ. Física E Esporte 2011, 25, 631–647. [Google Scholar] [CrossRef]
- Alves, M.A.R.; Oliveira, A.d.S.; Paes, M.J.; Stefanello, J.M.F. Psychological aspects of soccer and futsal players: A systematic review. Suma Psicológica 2022, 29, 30–47. [Google Scholar] [CrossRef]
- Rezvani, M.; Abdoli, B.; Vaez Mousavi, S.M. The Effect of Psychological Skills on Female Futsal Players’ Selected Sport Performance. Sport Psychol. Stud. 2018, 7, 1–6. [Google Scholar] [CrossRef]
- Sepasi, H.; Nourbakhsh, P.; Zarasvand, K.A.; Javadi, A.A. The relationships between sporting imagery, self confidence, and body mass index with sporting success in elite futsal athletes. Ann. Biol. Res. 2012, 3, 5293–5295. [Google Scholar]
- Röthlin, P.; Horvath, S.; Trösch, S.; Holtforth, M.G.; Birrer, D. Differential and shared effects of psychological skills training and mindfulness training on performance-relevant psychological factors in sport: A randomized controlled trial. BMC Psychol. 2020, 8, 1–13. [Google Scholar] [CrossRef]
- Birrer, D.; Morgan, G. Psychological skills training as a way to enhance an athlete’s performance in high-intensity sports. Scand. J. Med. Sci. Sports 2010, 20, 78–87. [Google Scholar] [CrossRef]
- Wylleman, P.; Alfermann, D.; Lavallee, D. Career transitions in sport: European perspectives. Psychol. Sport Exerc. 2004, 5, 7–20. [Google Scholar] [CrossRef]
- Dawadi, S.; Shrestha, S.; Giri, R.A. Mixed-methods research: A discussion on its types, challenges, and criticisms. J. Prac. Stud. Educ. 2021, 2, 25–36. [Google Scholar] [CrossRef]
- Creswell, J.W.; Plano Clark, V.L. Designing and Conducting Mixed Methods Research, 3rd ed.; Sage Publications: Thousand Oaks, CA, USA, 2017. [Google Scholar]
- Schoonenboom, J.; Johnson, R.B. How to construct a mixed methods research design. Koln. Z. Fur Soziologie Und Sozialpsychologie 2017, 69, 107. [Google Scholar] [CrossRef]
- Sheard, M.; Golby, J.; van Wersch, A. Progress toward construct validation of the Sports Mental Toughness Questionnaire (SMTQ). Eur. J. Psychol. Assess. 2009, 25, 186–193. [Google Scholar] [CrossRef]
- Martens, R.; Burton, D.; Vealey, R.S.; Bump, L.A.; Smith, D.E. Development and validation of the Competitive State Anxiety Intentory-2. In Competitive Anxiety Sport; Martens, R., Vealey, R.S., Burton, D., Eds.; Human Kinetics: Champaign, IL, USA, 1990; pp. 127–140. [Google Scholar]
- Smith, R.E.; Schutz, R.W.; Smoll, F.L.; Ptacek, J.T. Development and validation of a multidimensional measure of sport-specific psychological skills: The Athletic Coping Skills Inventory-28. J. Sport Exerc. Psychol. 1995, 17, 379–398. [Google Scholar] [CrossRef]
- Oppenheimer, D.M.; Meyvis, T.; Davidenko, N. Instructional manipulation checks: Detecting satisficing to increase statistical power. J. Exp. Soc. Psychol. 2009, 45, 867–872. [Google Scholar] [CrossRef]
- DeJonckheere, M.; Vaughn, L.M. Semistructured interviewing in primary care research: A balance of relationship and rigour. Fam. Med. Community Health 2019, 7, e000057. [Google Scholar] [CrossRef] [PubMed]
- Eberspächer, H. Mentales Training. Ein Handbuch für Trainier und Sportler; Copress Sportinform: München, Germany, 2004. [Google Scholar]
- Jones, B.J.; Kaur, S.; Miller, M.; Spencer, R.M.C. Mindfulness-based stress reduction benefits psychological well-being, sleep quality, and athletic performance in female collegiate rowers. Front. Psychol. 2020, 11, 572980. [Google Scholar] [CrossRef]
- Gardner, F.L.; Moore, Z.E. The Psychology of Enhancing Human Performance: The Mindfulness-Acceptance-Commitment (MAC) Approach; Springer Publishing Company: New York, NY, USA, 2007. [Google Scholar]
- Cooper, A.Z.; Richards, J.B. Lectures for adult learners: Breaking old habits in graduate medical education. Am. J. Med. 2016, 130, 376–381. [Google Scholar] [CrossRef] [PubMed]
- Gucciardi, D.F.; Gordon, S.; Dimmock, J.A. Evaluation of a mental toughness training program for youth-aged australian footballers: I. A quantitative analysis. J. Appl. Sport Psychol. 2009, 21, 307–323. [Google Scholar] [CrossRef]
- Saunders, B.; Sim, J.; Kingstone, T.; Baker, S.; Waterfield, J.; Bartlam, B.; Burroughs, H.; Jinks, C. Saturation in qualitative research: Exploring its conceptualization and operationalization. Qual. Quant. 2018, 52, 1893–1907. [Google Scholar] [CrossRef]
- Guest, G.; Namey, E.; Chen, M. A simple method to assess and report thematic saturation in qualitative research. PLoS ONE 2020, 15, e0232076. [Google Scholar] [CrossRef]
- Fugard, A.J.; Potts, H.W. Supporting thinking on sample sizes for thematic analyses: A quantitative tool. Int. J. Soc. Res. Methodol. 2015, 18, 669–684. [Google Scholar] [CrossRef]
- Braun, V.; Clarke, V. Successful Qualitative Research: A Practical Guide for Beginners; Sage Publications: Thousand Oaks, CA, USA, 2013. [Google Scholar]
- Vella, A. Languages and language varieties in Malta. Int. J. Biling. Educ. Biling. 2013, 16, 532–552. [Google Scholar] [CrossRef]
- Shapiro, S.S.; Wilk, M.B. An analysis of variance test for normality (complete samples). Biometrika 1965, 52, 591. [Google Scholar] [CrossRef]
- Mahalanobis, P.C. On the Generalized Distance in Statistics. Proc. Natl. Inst. Sci. India 1936, 12, 49–55. [Google Scholar]
- Astivia, O.L.; Zumbo, B.D. Heteroskedasticity in Multiple Regression Analysis: What it is, How to Detect it and How to Solve it with Applications in R and SPSS. Pract. Assess. Res. Eval. 2019, 24, 1. [Google Scholar] [CrossRef]
- Hedges, L.V.; Olkin, I. Statistical Methods for Meta-Analysis; Academic press: Cambridge, MA, USA, 2014. [Google Scholar]
- Lakens, D. Calculating and reporting effect sizes to facilitate cumulative science: A practical primer for t-tests and ANOVAs. Front. Psychol. 2013, 4, 863. [Google Scholar] [CrossRef] [PubMed]
- Cohen, J. Statistical Power Analysis for the Behavioral Sciences; Lawrence Erlbaum Associates: Hillside, NJ, USA, 1988. [Google Scholar]
- Primer, A.P. Quantitative methods in psychology. Psychol. Bull. 1992, 112, 155–159. [Google Scholar] [CrossRef]
- Braun, V.; Clarke, V. Reflecting on reflexive thematic analysis. Qual. Res. Sport Exerc. Health 2019, 11, 589–597. [Google Scholar] [CrossRef]
- Hussein, A. The use of triangulation in social sciences research: Can qualitative and quantitative methods be combined? J. Comp. Soc. Work. 2009, 4, 106–117. [Google Scholar] [CrossRef]
- Morse, J.M. Mixed Method Design: Principles and Procedures; Routledge: Oxfordshire, UK, 2016. [Google Scholar]
- Guetterman, T.C.; Fàbregues, S.; Sakakibara, R. Visuals in joint displays to represent integration in mixed methods research: A methodological review. Methods Psychol. 2021, 5, 100080. [Google Scholar] [CrossRef]
- Ong, N.C.; Chua, J.H. Effects of psychological interventions on competitive anxiety in sport: A meta-analysis. Psychol. Sport Exerc. 2020, 52, 101836. [Google Scholar] [CrossRef]
- Marín-González, F.H.; Portela-Pino, I.; Fuentes-García, J.P.; Martínez-Patiño, M.J. Relationship between sports and personal variables and the competitive anxiety of Colombian elite athletes of Olympic and Paralympic sports. Int. J. Environ. Res. Public Health 2022, 19, 7791. [Google Scholar] [CrossRef] [PubMed]
- Stamatis, A.; Grandjean, P.; Morgan, G.; Padgett, R.N.; Cowden, R.; Koutakis, P. Developing and training mental toughness in sport: A systematic review and meta-analysis of observational studies and pre-test and post-test experiments. BMJ Open Sport Exerc. Med. 2020, 6, e000747. [Google Scholar] [CrossRef]
- Azita, H.; Mousavi, M.V.; Shahla, P.; Hamidreza, T. Effectiveness of Psychological Preparation Program on Sport Performance of Futsal Girl Players: Mediating Role of Personality. J. Res. Med. Dent. Sci. 2019, 7, 92–101. [Google Scholar]
- Rees, T.; Haslam, S.A.; Coffee, P.; Lavallee, D. A Social Identity Approach to Sport Psychology: Principles, Practice, and Prospects. Sports Med. 2015, 45, 1083–1096. [Google Scholar] [CrossRef]
- Tajfel, H. The Achievement of Inter-group Differentiation. In Differentiation between Social Groups; Tajfel, H., Ed.; Academic Press: London, UK, 1978. [Google Scholar]
- Turner, J.C. Social categorization and the self-concept: A social cognitive theory. In Advances in Group Processes; Lawyer, E.J., Ed.; JAI Press: Stamford, CT, USA, 1985. [Google Scholar]
- Pandian, P.R.; Kumar, V.B.; Kannan, M.; Gurusamy, G.; Lakshmi, B. Impact of mental toughness on athlete’s performance and interventions to improve. J. Basic Clin. Physiol. Pharmacol. 2022, 13, 409–418. [Google Scholar] [CrossRef]
- Kent, S.; Devonport, T.J.; Lane, A.M.; Nicholls, W.; Friesen, A.P. The Effects of Coping Interventions on Ability to Perform Under Pressure. J. Sports Sci. Med. 2018, 17, 40. [Google Scholar]
- Worchel, S.; Rothgerber, H.; Day, E.A.; Hart, D.; Butemeyer, J. Social identity and individual productivity within groups. Br. J. Soc. Psychol. 1998, 37, 389–413. [Google Scholar] [CrossRef]
- González-Hernández, J.; Gomariz-Gea, M.; Valero-Valenzuela, A.; Gómez-López, M. Resilient resources in youth athletes and their relationship with anxiety in different team sports. Int. J. Environ. Res. Public Health 2020, 17, 5569. [Google Scholar] [CrossRef]
- Washif, J.A.; Ammar, A.; Trabelsi, K.; Chamari, K.; Chong, C.S.M.; Kassim, S.F.A.M.; Lew, P.C.F.; Farooq, A.; Pyne, D.B.; James, C. Regression analysis of perceived stress among elite athletes from changes in diet, routine and well-being: Effects of the COVID-19 lockdown and “Bubble” training camps. Int. J. Environ. Res. Public Health 2022, 19, 402. [Google Scholar] [CrossRef]
- Presta, V.; Vitale, C.; Ambrosini, L.; Gobbi, G. Stereopsis in sports: Visual skills and visuomotor integration models in professional and non-professional athletes. Int. J. Environ. Res. Public Health 2021, 18, 11281. [Google Scholar] [CrossRef] [PubMed]
- Inoue, A.; dos Santos Bunn, P.; Carmo, E.C.; Lattari, E.; da Silva, E.B. Internal Training Load Perceived by Athletes and Planned by Coaches: A Systematic Review and Meta-Analysis. Sports Med. Open 2022, 8, 35. [Google Scholar] [CrossRef]
- Mitić, P.; Nedeljković, J.; Bojanić, Ž.; Franceško, M.; Milovanović, I.; Bianco, A.; Drid, P. Differences in the psychological profiles of elite and non-elite athletes. Front. Psychol. 2021, 12, 635651. [Google Scholar] [CrossRef] [PubMed]
- Corrigan, J.A.; Onwuegbuzie, A.J. Toward a Meta-Framework for Conducting Mixed Methods Representation Analyses to Optimize Meta-Inferences. Qual. Rep. 2020, 25, 785–812. [Google Scholar] [CrossRef]
- McCambridge, J.; Witton, J.; Elbourne, D.R. Systematic review of the Hawthorne effect: New concepts are needed to study research participation effects. J. Clin. Epidemiol. 2014, 67, 267–277. [Google Scholar] [CrossRef]
- Kaur, M. Application of mixed method approach in public health research. Indian J. Community Med. 2016, 41, 93–97. [Google Scholar] [CrossRef]
- Stratton, S.J. Quasi-experimental design (pre-test and post-test studies) in prehospital and disaster research. Prehospital Disaster Med. 2019, 34, 573–574. [Google Scholar] [CrossRef]
- Jager, J.; Putnick, D.L.; Bornstein, M.H., II. More than just convenient: The scientific merits of homogeneous convenience samples. Monogr. Soc. Res. Child Dev. 2017, 82, 13–30. [Google Scholar] [CrossRef]
Mean (Pre) | Mean (Post) | Mean Difference | t | df | 2-Sided p | Hedge’s g | ||
---|---|---|---|---|---|---|---|---|
Pair 1 | SMTQ (Pre-Post) | 37.85 | 41.85 | −4.000 | −2.996 | 12 | 0.011 | 0.778 |
Pair 2 | CSAI-2-CA (Pre-Post) | 23.85 | 21.00 | −2.846 | 3.008 | 12 | 0.011 | 0.781 |
Pair 3 | CSAI-2-SA (Pre-Post) | 19.15 | 18.08 | 1.077 | 0.783 | 12 | 0.449 | 0.203 |
Pair 4 | CSAI-2-SC (Pre-Post) | 24.31 | 24.92 | −0.615 | −0.581 | 12 | 0.572 | 0.151 |
Pair 5 | ACSI-28 (Pre-Post) | 45.38 | 50.62 | −5.231 | −2.775 | 12 | 0.017 | 0.720 |
Beta | R | R2 | F | p | df (Res/Reg) | |
---|---|---|---|---|---|---|
SMTQ (Post) | 0.405 | 0.405 | 0.164 | 2.157 | 0.170 | 1/11 |
CSAI-2-CA (Post) | −0.372 | 0.372 | 0.138 | 1.764 | 0.211 | 1/11 |
CSAI-2-SA (Post) | −0.477 | 0.477 | 0.228 | 3.242 | 0.099 | 1/11 |
CSAI-2-SC (Post) | 0.648 | 0.648 | 0.420 | 7.971 | 0.017 | 1/11 |
ACSI-28 (Post) | 0.646 | 0.646 | 0.418 | 7.897 | 0.017 | 1/11 |
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Vella-Fondacaro, D.; Romano-Smith, S. The Impact of a Psychological Skills Training and Mindfulness-Based Intervention on the Mental Toughness, Competitive Anxiety, and Coping Skills of Futsal Players—A Longitudinal Convergent Mixed-Methods Design. Sports 2023, 11, 162. https://doi.org/10.3390/sports11090162
Vella-Fondacaro D, Romano-Smith S. The Impact of a Psychological Skills Training and Mindfulness-Based Intervention on the Mental Toughness, Competitive Anxiety, and Coping Skills of Futsal Players—A Longitudinal Convergent Mixed-Methods Design. Sports. 2023; 11(9):162. https://doi.org/10.3390/sports11090162
Chicago/Turabian StyleVella-Fondacaro, Daniel, and Stephanie Romano-Smith. 2023. "The Impact of a Psychological Skills Training and Mindfulness-Based Intervention on the Mental Toughness, Competitive Anxiety, and Coping Skills of Futsal Players—A Longitudinal Convergent Mixed-Methods Design" Sports 11, no. 9: 162. https://doi.org/10.3390/sports11090162
APA StyleVella-Fondacaro, D., & Romano-Smith, S. (2023). The Impact of a Psychological Skills Training and Mindfulness-Based Intervention on the Mental Toughness, Competitive Anxiety, and Coping Skills of Futsal Players—A Longitudinal Convergent Mixed-Methods Design. Sports, 11(9), 162. https://doi.org/10.3390/sports11090162