Mindfulness-Acceptance-Commitment Research Articles

Exploring mindfulness interventions across cultures: a comparative meta-analysis of mindfulness interventions for athletes in Western and Eastern contexts.

Applying mindfulness training across cultures can be challenging because its internal motivation depends on values, but there are differences between Western and Eastern contexts. This meta-analysis examines the comparative impacts of the Western Mindfulness-Acceptance-Commitment (MAC) approach and the culturally-adapted Chinese Mindfulness-Acceptance-Insight-Commitment (MAIC) mindfulness training for athletes, to explore the importance of cultural adaptation in cross-cultural psychology to psychological skills training. This meta-analysis was registered with Prospero (ID: CRD42023474474) and adhered to the PRISMA principles. The PICO search methodology was employed to identify pertinent Chinese and English literature across six databases (Web of Science, PubMed, Scopus, CNKI, Wanfang, and VIP) from 2003 to 2023. The evidence originated from randomized controlled trials. Effect sizes were evaluated across three primary domains: athletic performance, mindfulness, and psychological flexibility, and heterogeneity and publication bias. Both MAC and MAIC demonstrated positive effects across all outcome categories in 18 studies. MAIC exhibited substantially larger effect sizes compared to MAC. In mindfulness (MAIC: g = 1.273, p < 0.001; MAC: g = 0.521, p = 0.001), sports performance (MAIC: g = 0.945, p = 0.015; MAC: g = 0.550, p < 0.001), MAC did not provide evidence of improved psychological flexibility (g = 0.076, p = 0.747), while MAIC demonstrated significant benefits (g = 0.964, p < 0.001). While MAIC is based on MAC, it yields more significant outcomes. This may be the "Insight" component introduced by MAIC, which skillfully integrates Eastern context. The MAIC strategy not only becomes more appropriate for local athletes but also indirectly enhances their mindfulness, athletic performance, and psychological flexibility, resulting from cultural adaptation. The new idea not only solves the culture shock caused by the direct application of Western MAC approach on Chinese athletes, but also provides a new solution to the problem that there is insufficient evidence to support the effect of the MAC approach on "psychological flexibility." Investigating differential effects between MAC and MAIC contributes to understanding the significance of culturally adapting mindfulness training and transnational movement of practices. The findings will assist practitioners in selecting evidence-based protocols tailored to athlete needs and cultural contexts. Prospero (ID: CRD42023474474).

A 6-Week Mindfulness-Acceptance-Commitment Intervention to Improve Professional Ballet Dancers' Psychological States Around Performance.

Background: Mindfulness and acceptance-based approaches have been trialled in professional sport. The present pilot study was a randomized controlled trial with professional ballet dancers investigating the effectiveness of the Mindfulness-Acceptance-Commitment (MAC) approach, developed for athletes, compared to an education program which included topics relevant to ballet and performance. Methods: Participants included 16 professional ballet dancers (2 men and 14 women) who were randomly assigned into either the MAC or education group for 1 session per week, for 6 weeks. Participants were assessed pre-and post-intervention using the Mindfulness Inventory for Sport (MIS) and the Acceptance Action Questionnaire (AAQ-II). Within 2 weeks of the final mindfulness session, all participants completed a semi-structured interview. Results: No differences were found when comparing the questionnaire responses between pre- and post- intervention, nor between the MAC group and the control group at post intervention for all subscales. Although dancers reported in the interviews that the sessions were valuable, they advised their ability to dedicate time to mindfulness ongoing would be challenging. Conclusions: Mindfulness interventions, as explored in this study, show promise to promote the well-being of professional ballet dancers. For consistent and ongoing mindfulness practice, future designs should seek to embed mindfulness practice into dancer and company schedules.

Yoga and Mindfulness Training for Professional Baseball Players: A Narrative Study on Perspectives and Practices.

Mindfulness-related practices (e.g., yoga) appear aligned with the field of athletic performance in developing sport-related capacities such as attention regulation, volition, perception, and coping. The purpose of the present narrative study was to explore the experiences of professional baseball players who interacted with the ideas and practices of mindfulness presented in classes featuring yoga and Mindfulness-Acceptance-Commitment (MAC). Participants were seven Minor League Baseball players who learned mindfulness practices in off-season instructional classes and then completed semi-structured episodic interviews on how their mindfulness practices were perceived and utilized in training and competition during the baseball season. Data were analyzed using the three-dimensional space approach to examine participants' subjective accounts of experience, behavior, environmental conditions, and external events. Individual narratives were re-storied and themed. Results indicated various themes across settings, from players' experiences in the yoga/MAC classes (effect of breath regulation on coping strategies; self-awareness and the mind-body connection), on the baseball field (confidence and self-efficacy; self-regulation; resilience and positive coping strategies), and off the baseball field (everyday life and activities; stigma of mental training). Overall, participants appeared to be accepting of mindfulness integrated into their training and provided perspectives supporting the benefits of yoga/MAC classes. This study has research and practice implications in incorporating yoga and mindfulness-based practices in athletic performance among young professional athletes.

A cluster randomized trial of a rational emotive behavior therapy (REBT) program and a mindfulness-acceptance-commitment (MAC) program, with South African adolescent rugby players

Until recently, research examining the application of Rational Emotive Behavior Therapy (REBT) in sports settings was virtually absent in South Africa. Despite the growing evidence of REBT's potential as a psychological intervention in Western nations, its use within the multicultural and sports-fervent context of South Africa remains unexplored. Moreover, limited research has addressed the impact of REBT on rugby players, with only a few case studies being reported. The current experiment employs a cluster randomized trial (CRT) to compare the effects of a 7-week preferential REBT program with a 7-week Mindfulness-Acceptance-Commitment (MAC) program on irrational beliefs, competitive anxiety and subjective performance, among adolescent South African rugby players. We also include a wait-list control group who received neither REBT nor MAC. Results indicate that athletes receiving REBT reported greater improvements in irrational beliefs, anxiety, and subjective performance, while that athletes receiving MAC also reported some improvements in anxiety. This study highlights the potential of REBT as a valuable psychological intervention in the context of South African adolescent rugby players.

Examining the effects of the Mindfulness-Acceptance-Commitment (MAC) programme on sport-specific dispositional mindfulness, sport anxiety, and experiential acceptance in Martial Arts

The aim of the study was to examine effects of the Mindfulness-Acceptance-Commitment (MAC) programme on sport-specific dispositional mindfulness, sport anxiety, and experiential acceptance, compared to an inactive control group, in a population of Martial Arts (MA) athletes. Twenty-three MA athletes were subjected to the MAC intervention, and 22 MA athletes comprised the control group. To analyse potential differences in the outcome variables between the two groups, Bayesian repeated measures analysis of variance (RM-ANOVA) was used. Findings showed that the MAC-group had greater increases over time in the sport-specific mindfulness subscales awareness and acceptance and acceptance, compared to the control group. In contrast, no interaction effects were found for present moment attention (AMQ), experiential acceptance (BEAQ), and sport anxiety (SAS-2). Overall, the present study adds further information and understanding about the effectiveness and implementation of the MAC programme.

Integrating Mindfulness to Reduce Injury Rates in Athletes: A Critically Appraised Topic

Clinical Question: Is there evidence to support the use of mindfulness to reduce injury risk in athletic populations? Clinical Bottom Line: There is currently inconsistent, good-quality evidence to support that mindfulness interventions are effective in decreasing injury rates in athletes compared to the standard of care. Future research should investigate the effectiveness of mindfulness in other populations and types of sports activity (e.g., basketball, gymnastics, etc.). Additionally, future research should investigate different mindfulness delivery techniques in addition to the Mindfulness–Acceptance–Commitment (MAC) approach. Due to the inconsistent, good-quality evidence to support the use of mindfulness to reduce injury rates, the grade of B is recommended by the Strength of Recommendation Taxonomy. Mindfulness interventions should be incorporated into clinical practice but stakeholders (e.g., coaches, athletes, administration) should be included in the decision to implement these programs.

Effects of mindfulness training on resilience, self-confidence and emotion regulation of elite football players: The mediating role of locus of control

This study investigated effects of mindfulness training on resilience, self-confidence and emotion regulation of elite football players as well as mediating role of locus of control. The study recruited 34 participants which were assigned into experimental (n=17) and control (n=17) groups. Age ranged between 16 and 32years (M age = 22.6years, SD = 1.47). The experimental group received 8 weeks mindfulness acceptance commitment (MAC) intervention program, while control group received no intervention. Participants completed Five Facet Mindfulness Questionnaire (FFMQ), The Connor-Davidson Resilience scale (CD-RISC), Trait Sport Confidence Inventory (TSCI), Emotion Regulation Questionnaire (ERQ) and Adapted Levenson Multidimensional Locus of control scales (ALMLC). Both groups completed the questionnaire at pre-test and post-test evaluation. Descriptive data employed mean and standard deviation, while Structural Equation Modelling (SEM) of Sӧrbom's method (alternative to analysis of covariance) was used for analysis of hypothesis. Finding of the study showed that there is significant direct and indirect effect of mindfulness acceptance commitment on resilience, self-confidence and emotion regulation on elite football players. The findings further showed that there is significant difference between the pre-test scores and post-test scores of intervention group and control group. The intervention group mean scores on resilience, self-confidence and emotion regulation are higher than the control group counterparts. This shows that MAC program is effective in increasing resilience, self-confidence and emotion regulation of elite football players concurrently which in turn could improve performance and attain success.

The Effectiveness of a Mindfulness Training Program on Selected Psychological Indices and Sports Performance of Sub-Elite Squash Athletes.

Mindfulness Acceptance Commitment (MAC) programs have garnered much support in enhancing sport performance through present-moment focus and non-judgmental thoughts. Expanding on previous studies conducted in collegiate and professional settings, the current study investigates the application of MAC amongst national sub-elite athletes. The study was conducted utilizing a single case A-B design, with a total of six sub-elite Malaysian Squash athletes (2 males, 3 females; Mage = 15 ± 2 years) purposively sampled from the Malaysian national squash team. Participants underwent 6 weeks of baseline testing, 7 weeks of program intervention, and a retention test 4 weeks post-intervention. The intervention consisted of psycho-education, centering and cognitive defusion among other aspects as purported in MAC programs. Changes in proficiency of mindful practice was observed through the Mindfulness Awareness Acceptance Scale (MAAS), experiential avoidance through the Acceptance Action Questionnaire (AAQ-II), stress levels through the Perceived Stress Scale (PSS), and sport performance through both coach- and self-rated scales. Overall, visual analysis revealed improvements in MAAS levels (M = 1.15 ± 0.15), with no marked changes in AAQ-II (M = –0.002 ± 1.12) and PSS (M = 0.7 ± 0.93) after 7 weeks of intervention. Coach-rated sport performance also improved across the phases (M = 0.86 ± 0.93), with mixed responses for self-rated improvements (M = 0.01 ± 1.19). Overall, the benefits of MAC program were well-maintained past the post-intervention phase. The current study supported the implementation of an MAC program for sub-elite athletes in real-world settings.

Examining the Effects of Mindfulness–Acceptance–Commitment Training on Self-Compassion and Grit among Elite Female Athletes

Background: Mindfulness-based interventions are well-established in the field of psychotherapy, and such interventions have also gained increased attention in the field of sport psychology, either to cope with psychological pressure or to improve an athlete’s performance. The goal of the present study was to examine whether a Mindfulness–Acceptance–Commitment (MAC) program could increase self-compassion and grit among elite female athletes compared to an active control condition. To this end, we performed a randomized trial among female adult athletes. Methods: Forty female adult athletes (Mage = 22.22, SD = 2.40) were randomly assigned either to the Mindfulness–Acceptance–Commitment group (n = 20; 7 group sessions, 60 min each) or the active control group (n = 20; 7 group sessions, 60 min each). At baseline, seven weeks later at the end of the study and again four weeks later at follow-up, participants completed a series of self-rating questionnaires on mindfulness, self-compassion and grit. Results: Dimensions of mindfulness, self-compassion and grit improved over time, but more so in the Mindfulness–Acceptance–Commitment condition compared to the active control condition. Improvements remained stable from the study end to follow-up. Conclusions: While the active control condition improved dimensions of mindfulness, self-compassion and grit among female adult athletes, improvements were much stronger in the Mindfulness–Acceptance–Commitment condition. Importantly, improvements in the Mindfulness–Acceptance–Commitment condition remained stable over a time lapse of four weeks at follow-up after study completion, suggesting that the Mindfulness–Acceptance–Commitment intervention appeared to improve cognitive–emotional learning processes.

Effect of a 7-week Mindfulness-Acceptance-Commitment intervention programme on mental toughness: An experimental study of male league softball players

Mental toughness is viewed as an important psychological variable that could assist athletes to perform successfully in sport. This study investigated the effects of a Mindfulness-Acceptance-Commitment (MAC) intervention programme on the mental toughness of male league softball players. It was hypothesised that players participating in the experimental group will report significantly higher mental toughness scores than those in a control group. A purposive sample of two teams randomly assigned to an experimental (n=9) and control group (n=8) from two different provinces, representing 17 players with a mean age of 23.41 years (9.36) was invited to participate in the study. Players in the experiment group received a 7-week MAC intervention programme, while those in the control group did not. Mental toughness was assessed with the Sports Mental Toughness Questionnaire (SMTQ). The non-parametric Wilcoxon Signed Rank tests and Mann-Whitney U-tests undertaken to analyse within-and-between-group differences at pre and post-test levels and consequently to determine the effects of the MAC programme on the softball players. The results indicated that the experimental group had significantly higher mental toughness than the control group at the post-test, thus confirming that the MAC intervention had a statistically significant effect (p=.000) on the mental toughness of the softball players. The MAC programme appeared to be a valuable intervention in securing the mental toughness of softball players.

The Use of Mindfulness Acceptance Commitment (MAC) Approach For Malaysian Elite Triathletes

Mindfulness Acceptance Commitment (MAC) approach has been introduced into the sport psychology field and has shown a lot of interest in the applied practices. Athletes who receive MAC approach are taught to deal with challenging internal experiences in a non-judgmental way, choosing to persist with their task-at-hand despite discomforts and to remain focused on being grounded at the present moment. In Malaysia, the elite triathletes have not been exposed to the MAC approach before. This paper aims to describe how the MAC approach was provided to the Malaysian elite triathletes. MAC was taught over six weeks, with one MAC theme introduced per week. Each triathlete was given a one-on-one session of 60-90 minutes per week with homework and practical exercises. After six weeks, the triathletes reported marked improvement in their sport and additional improvements in other domains of their life. Considering the promising improvements of the elite triathletes who received the MAC approach, it is worth considering that the MAC approach should be adapted and incorporated into the triathlon sport.

College Students’ Test Anxiety and Listening Test Scores: CB and MAC-Based Psychoeducation Vs. No Treatment Control

ABSTRACT The purpose of this study was to compare two psychoeducation interventions of cognitive behavioral (CB) and mindfulness acceptance commitment (MAC)-based models against a no treatment control (NTC) group with test anxiety and exam scores on a written and music listening test. Three sections of an undergraduate course participated (N = 104), with each assigned to a condition: (a) CB psychoeducation (n = 40), (b) MAC psychoeducation (n = 26), and (c) NTC group (n = 38). Participants in the CB and MAC psychoeducation received two 20-minute PowerPoint lectures that described the theoretical principles of their assigned condition and were encouraged to utilize the material in managing their test anxiety. CB and MAC-based psychoeducation improved participants’ knowledge of these models and improved test scores on music listening tests. Results suggest that CB and MAC-based psychoeducation are promising interventions for improving listening test scores and should be further studied.

Effects of Mindfulness-Acceptance-Commitment (MAC) on Sport-Specific Dispositional Mindfulness, Emotion Regulation, and Self-Rated Athletic Performance in a Multiple-Sport Population: an RCT Study

ObjectivesThe aim of the study was to examine mediating effects of emotion regulation and sport-specific dispositional mindfulness on self-rated athletic training performance, following the Mindfulness-Acceptance-Commitment (MAC) intervention, compared to a Psychological Skills Training (PST) control group.MethodsSixty-nine competitive elite athletes who did not have any prior experience with mindfulness- and acceptance-based exercises, were recruited and randomly assigned into either a MAC group or a traditional PST group. Latent growth curve analyses were performed to examine longitudinal relationships among the study variables. Mediation analyses were conducted to test if the growth trajectory of each of the proposed mediators mediated the relationship between the intervention and perceived performance (measured at T3).ResultsFindings showed that the MAC intervention had an indirect effect on self-rated athletic training performance through changes in dispositional mindfulness and emotion regulation respectively. Further, the MAC- group obtained greater post-test improvements in athletic mindfulness, emotion regulation abilities, and perceived performance compared to the PST group.ConclusionsOverall, findings suggest that dispositional athletic mindfulness and emotion regulation may function as important mechanisms in MAC, and that the MAC approach is a more effective intervention compared to the PST condition in reducing emotion regulation difficulties, as well as enhancing sport-relevant mindfulness skills and perceived athletic training performance in elite sport.

Practitioners’ reflections of working with the Mindfulness-Acceptance-Commitment (MAC) approach in team sport settings

The aim of this article was to describe the implementation of a team-based MAC intervention, and discuss important aspects to consider when implementing the MAC protocol in elite team sports. The MAC program contains seven modules in which core concepts such as mindfulness, acceptance, and values-driven behavior are being taught and practiced. We experienced conceptual as well as practical challenges in the application of the MAC protocol. A general recommendation in implementing MAC concepts and exercises for teams is to make the content of the program sport-specific.

Effectiveness of the mindfulness-acceptance-commitment-based approach on athletic performance and sports competition anxiety: a randomized clinical trial.

BackgroundImproving sports performance and reducing anxiety is one of the most important goals of athletes. Recurrence of symptoms and treatment cessation are common problems with common interventions. Approaches based on mindfulness-acceptance-commitment (MAC) can be a response to these limitationsObjectiveThe main purpose of the present study was to determine effectiveness of the mindfulness-acceptance-commitment-based approach to athletic performance enhancement and sports competition anxiety in students who have had athletic experience for 3 to 5 years.MethodsThis randomized clinical trial was conducted at the Faculty of Educational Sciences of Iran University of Medical Sciences in Tehran, Iran, from May 1, 2017 to September 15, 2017. A total of 31 students were randomly assigned to experimental (n=15) and control groups (n=16). The experimental group received the protocol Mindfulness-Acceptance-Commitment (MAC) for 8 sessions. Subjects completed the Charbonneau Sports Performance Questionnaire, Action and Acceptance Questionnaire (AAQ) and Sports Competition Anxiety Test (SCAT) Questionnaire. Data analysis was conducted by using multivariate covariance analysis (MANCOVA) by SPSS-22.ResultsThe results of the study indicated that the MAC approach increases significantly the performance of basketball playing athletes (p<0.05). Furthermore, the MAC approach decreases significantly experiential avoidance and sports anxiety in athletes (p<0.05). The size of the difference between the groups is moderate (Eta squared).ConclusionsThis study revealed that the mindfulness-acceptance-commitment-based approach is an effective intervention to increasing athletic performance and reducing experiential avoidance and sports anxiety in athletes.Trial registrationThe trial was registered at the Iranian Registry of Clinical Trials (http://www.irct.ir) with the Irct ID: IRCT20170409033333N1.FundingThis study has been financially supported by the Research Deputy of Iran University of Medical Sciences (Code: 95-04-185-29333).

Acceptance and commitment therapy as a clinical anxiety treatment and performance enhancement program for musicians

In this article we discuss the various options available to musicians wanting to treat their music performance anxiety (MPA), and we recommend that musicians work with a performance psychologist over the other available options. We also discuss the potential for Acceptance and Commitment Therapy (ACT) to serve as both a clinical anxiety treatment and performance enhancement program for musicians, while addressing the state of the research for both applications, as well as the research for a similar, mindfulness and acceptance-based performance enhancement program for athletes, i.e., the Mindfulness–Acceptance–Commitment (MAC) approach. In order for the field of performance psychology to develop into a more credible discipline, we believe practitioners working with musicians should follow an evidence-based practice model of care, in which empirically supported treatments for MPA and performance enhancement are promoted, and information about such treatments is disseminated among practitioners, musicians, and music teachers. Such a practice must become the norm in this field, because it will ultimately result in greater protections for those musicians seeking help for performance-related challenges by ensuring a higher level of professional accountability among practitioners. Lastly, we discuss some issues that may arise when applying ACT or the MAC approach to musicians.

Mindfulness y rendimiento deportivo

Resumen: La inclusión del mindfulness en el deporte es un campo reciente. Mientras que la psicología del deporte ha dependido principalmente de la “segunda ola” de intervenciones cognitivo-conductuales durante las últimas cuatro décadas, una nueva aproximación que incluye al mindfulness se ha desarrollado recientemente: la “tercera ola”. Esta nueva aproximación asume la idea de que el rendimiento es un estado que no se basa en el auto-control o cambio del comportamiento, sino que es un estado que emerge del reconcomiendo y aceptación de los pensamientos, emociones y sensaciones corporales. La práctica del mindfulness permite aprender a observar y aceptar los pensamientos, emociones y sensaciones corporales sin intentar eliminarlos o modificarlos. Este trabajo revisa los dos principales programas de mindfulness para el rendimiento deportivo, ambos de la “tercera ola”: el Mindful Sport Performance Enhancement (MSPE) y el Mindfulness-Acceptance-Commitment (MAC). Mindfulness and sport performance Abstract: Mindfulness in sports is a recent field. While sport psychology relied mainly on “second wave” cognitive-behavioural interventions for the last four decades, a new approach has recently been developed in sport psychology including mindfulness: a “third wave” approach. This new approach assumes that ideal performance is a state that is not based on self-control or change in behaviour, but rather a state that arises from recognition and acceptance of thoughts, emotions and bodily sensations. Practicing mindfulness allows learns to observe and accept the thoughts, emotions, and body sensations, without making any attempt to eliminate or modify them. This paper reviews the main programs of mindfulness in sport performance both from the “third wave”: Mindful Sport Performance Enhancement (MSPE) and Mindfulness-Acceptance-Commitment (MAC).

An empirical examination comparing the Mindfulness-Acceptance-Commitment approach and Psychological Skills Training for the mental health and sport performance of female student athletes

The present study was a randomised controlled trial investigating the effectiveness of the Mindfulness-Acceptance-Commitment (MAC) approach compared to traditional Psychological Skills Training (PST) for the mental health and sport performance of female collegiate athletes. Two hypotheses were proposed: (a) participants in the MAC group would demonstrate reduced behavioural issues, emotional distress, and psychological symptoms, and increased athletic performance when compared to those in the PST group; (b) MAC participants would exhibit reduced emotion dysregulation and increased psychological flexibility and dispositional mindfulness, compared to PST participants. Participants included 18 National Collegiate Athletic Association Division III female student athletes who were randomly assigned into either the MAC or PST group based upon pre-intervention levels of distress; and were assessed pre-intervention, post-intervention, and at 1-month follow-up. A mixed-model ANOVA analysis revealed that the MAC effectively reduced Substance Use, Hostility, and Emotion Dysregulation over time when compared to the PST group. Several within-group differences also emerged, as MAC participants demonstrated reduced Generalised Anxiety, Eating Concerns, and Psychological Distress, as well as increased psychological flexibility from post-intervention to one-month follow-up. As per coach ratings, MAC participants also evidenced improved sport performance from pre-intervention to post-intervention. Results suggest that the MAC is an effective intervention for the mental health and sport performance needs of female collegiate athletes.

운동선수의 수행향상을 위한 심리지원 프로그램 적용 및 평가 -마음챙김･수용전념(MAC)접근을 중심으로-*

운동선수의 수행향상을 위한 심리지원 프로그램 적용 및 평가 -마음챙김･수용전념(MAC)접근을 중심으로-*

Theoretical and Empirical Developments of the Mindfulness-Acceptance-Commitment(MAC) Approach to Performance Enhancement

As long as athletes strive to attain optimal performance states and consistently reach high performance goals, psychological interventions will be used to assist in the development of skill and the maintenance of performance. In the pursuit of these goals, newer evidence-driven models based on mindfulness- and acceptance-based approaches have been designed to achieve these ends. Based upon questionable efficacy data for traditional psychological skills training procedures that emphasize reduction or control of internal processes, mindfulness- and acceptance-based approaches develop skills of nonjudging mindful awareness, mindful attention, and experiential acceptance to aid in the pursuit of valued goals. The most formalized and researched mindfulness- and acceptance-based approach within sport psychology is the manualized Mindfulness-Acceptance-Commitment (MAC) protocol. In the 8 years since the MAC was first developed and presented, and the 5 years since the first publication on the protocol, the MAC program has accumulated a continually growing empirical base for both its underlying theory and intervention efficacy as a performance enhancement intervention. This article reviews the empirical and theoretical foundations of the mindfulness- and acceptance-based approaches in general, and MAC in particular; reviews the accumulated empirical findings in support of the MAC approach for performance enhancement; and presents recent MAC developments and suggested future directions.