The Concept and History of Coaching

- The 1970s: The Birth of the Inner Game
The concept of coaching first began to take shape in the 1970s. Professional tennis coach Timothy Gallwey introduced the "Inner Game" — a question-based approach designed to remove internal obstacles and promote self-directed learning in athletes [1]. This approach represented a clear departure from traditional directive and command-based instruction, and it had a lasting influence on the development of coaching as a discipline. Gallwey placed emphasis not only on technical skill, but on the internal mental state of the athlete — highlighting the importance of self-awareness and personal responsibility.

- The 1990s: The Spread of Coaching in the United States
In the 1990s, the "Inner Game" evolved into what became widely known as "coaching," spreading rapidly across the United States in business and personal development contexts [1][2]. John Whitmore built on Gallwey's ideas and developed the concept of business coaching further. He established the GROW model — Goal, Reality, Options, Will — which provided a systematic framework for the entire coaching process. This model was widely adopted in business coaching practice and has been supported by empirical evidence of its effectiveness. Coaching became an indispensable tool for leadership development and individual performance improvement in organizations.

- The Late 2000s: Introduction to Japan and Diverse Interpretations
In Japan, coaching began to be introduced primarily in business settings from the late 2000s onward. In its early stages, definitions and understandings of the concept varied considerably and lacked consistency. In sports contexts, for example, "coaching" tended to be understood as synonymous with "instruction," while in business contexts it was positioned as a method of fostering intrinsic motivation and capability development through dialogue. For the purposes of this assessment, coaching is defined as a communication approach that promotes self-expression and goal achievement through dialogue.

The Development of Coaching Scales: Domestic and International Trends
A wide range of scales have been developed both internationally and in Japan to measure and evaluate the effectiveness and quality of coaching.

- International Trends in Scale Development
In Western countries, the professionalization of coaching and the growing emphasis on evidence-based practice have led to the development of various assessment tools.

- Outcome evaluation scales: Numerous scales have been developed to measure the extent to which coaching contributes to goal achievement, self-efficacy, wellbeing, and performance improvement. Research conducted by the International Coaching Federation (ICF) represents one example [3].

- Skill evaluation scales: Many scales have also been developed to assess coach skills and competencies, including the Coaching Session Evaluation Scale (CSES), which is based on the ICF Core Competencies [4][5].

- Meta-analyses: In recent years, a growing number of meta-analyses have been conducted to synthesize evidence on the effectiveness of coaching. These studies suggest that workplace coaching has a positive impact on skill acquisition, emotional regulation, and organizational outcomes — though the need for more rigorous research has also been noted [6][7].

- Trends in Scale Development in Japan
In Japan, scale development has drawn on international findings while adapting to cultural contexts and practical applications.

- Hamada & Shoji (2013): In the field of Japanese sports psychology, a coaching scale was developed that reflects cultural characteristics and athlete tendencies. The research suggested that coaching has the potential to contribute to intrinsic motivation and performance improvement [8].

- Shimamoto et al. (2015): Developed a scale for multidimensional evaluation of coaching behaviors in sports settings. Measurement items included communication skills, quality of feedback, and the ability to draw out athlete initiative — contributing to the design of practical training and instructional approaches [9]. - Shimizu et al. (2018): Developed an evaluation scale aimed at cultivating effective coaches, conducting multifaceted analysis of the coach-athlete relationship. The study examined the psychological effects on athletes and presented practical guidelines for use in real coaching environments [10].

These prior studies were referenced in the development of this scale.

A team of active business leaders, certified psychologists, clinical psychologists, and graduates of psychology master's programs conducted brainstorming sessions, followed by a grouping process. This resulted in six categories. After further review, four questions were assigned to each factor, producing a scale of 24 items in total.

- Rapport Building
1. I proactively approach others with a smile.
2. I frequently express gratitude to those around me.
3. I am good at keeping conversation going in a relaxed and natural way.
4. I am comfortable using humor and lightheartedness in interactions.

- Active Listening
5. I can listen with genuine empathy even when I am busy.
6. I reflect back and organize the other person's thoughts clearly.
7. I can wait through silences without feeling anxious.
8. I am able to draw out the other person's core values through conversation.

- Assessment Ability
9. I can systematically identify a person's strengths and areas for growth.
10. I seek to understand the values behind a person's actions.
11. I can identify patterns in how the other person thinks.
12. I can articulate specific development goals for the person going forward.

- Feedback Skills
13. I always create opportunities to give feedback.
14. I make sure to acknowledge and praise the other person's efforts and actions.
15. I communicate areas for improvement in a clear and accessible way.
16. I use a structured cycle of planning, action, review, and improvement.

- Motivational Support
17. I always help the other person visualize what success will look like after achieving their goal.
18. I actively assign work that allows a high degree of autonomy.
19. I consistently let the other person know that I am paying attention to them.
20. I celebrate their successes genuinely and wholeheartedly.

- Developing Problem-Solving Ability
21. I encourage the other person to articulate and test their hypotheses.
22. I have them analyze the causes of inconsistency in their results.
23. I prioritize learning over outcomes in our conversations.
24. I repeatedly provide opportunities to try again after setbacks.

● Number of Questions

6 factors × 4 questions each

● 5-Point Scale

Strongly Disagree　　0

Disagree　　　　　　1

Neutral　　　　　　　2

Agree　　　　　　　　3

Strongly Agree　　　4

● High / Moderate / Low Threshold per Factor

12 to 16　　Good　　8 to 11　　Fair　　0 to 7　　Poor

● Overall Score Thresholds

78 to 96　　Excellent

64 to 77　　Good

49 to 63　　Fair

0 to 48　　　Poor

For each score level, we provided an evaluation of approximately 1,000 characters covering key characteristics and points to be aware of. The content was developed based on prior research and the clinical experience of the authors.

This assessment has not been subjected to factor analysis or checks for reliability and validity. It reflects the professional judgment of specialists, but please note that it lacks sufficient statistical grounding and is not intended for use in academic research.

[1] Gallwey, W. T. (1974). The Inner Game of Tennis. Random House.
[2] Whitmore, J. (1992). Coaching for Performance: GROWing People, Performance and Purpose. Nicholas Brealey Publishing.
[3] International Coaching Federation. (2020). 2020 ICF Global Coaching Study. ICF.
[4] International Coaching Federation. (n.d.). ICF Core Competencies.
[5] Baron, L., & Morin, S. (2009). The Coaching Session Evaluation Scale (CSES): Development and preliminary validation. International Journal of Coaching in Organizations, 7(1), 84–98.
[6] Theeboom, T., Beersma, B., & van Vianen, A. E. M. (2014). Does coaching work? A meta-analysis on the effects of coaching on individual level outcomes in an organizational context. The Journal of Positive Psychology, 9(1), 1–18.
[7] Sonesh, S. C., Coultas, C. W., Lacerenza, C. N., Marlow, S. L., Benishek, L. E., & Salas, E. (2015). The power of coaching: A meta-analytic investigation. Journal of Organizational Behavior, 36(1), 1–30.
[8] Hamada, Y., & Shoji, Y. (2013). A study on the psychological effects of coaching. Transactions of Japan Society of Kansei Engineering, 12(2), 165–171.
[9] Shimamoto, Y., Tsubosaka, K., Kiuchi, A., & Ishii, M. (2015). Development of a sports coaching skills scale to promote life skills acquisition. Sasakawa Sports Foundation Research Grant Report.
[10] Shimizu, T., Enomoto, K., Nukaga, S., & Arai, H. (2018). Development of a coaching evaluation scale for good coach development and its relationship with athletes. Sasakawa Sports Research Grant Report, 307–313.