As a health and exercise professional, you know that building rapport with clients is crucial for effective coaching. Recent research conducted at Fujita Health University revealed that smiling during conversations plays a significant role in establishing positive interpersonal connections. This study quantified the effects of one person’s smile on another person, offering practical applications for pros who are looking to create stronger bonds with their clients. Here’s how understanding the science of smiles can enhance your coaching practice and contribute to client success.

The Science of Smiling

Smiling during face-to-face conversations has long been associated with positive social interactions, but this research is the first to measure how one person’s smile intensity directly influences the smile of the person it is directed at. Using advanced facial recognition software, the study observed 40 participants engaged in three-minute conversations. These interactions varied by the listener’s level of smiling—minimal, moderate and greater intensity. Results showed a powerful effect: when listeners smiled more, speakers responded with increased smiling intensity and frequency, especially in same-sex pairs.

Lead researcher and professor Yohei Otaka explained why his team chose to study this effect. “If one smiles more during a conversation, the other person will also smile more, which can lead to a better interpersonal relationship with each other.” This reciprocal influence highlights the potential of smiling to foster a welcoming and supportive atmosphere—a valuable insight as you work to establish trust and develop motivation in you clients.

Smile Synchronization and Client Receptiveness

The research showed that smile synchronization (where both parties smile at similar moments) occurred across all types of pairs, regardless of gender, supporting the idea that smiling is a universal tool for social bonding. Importantly, participants reported higher levels of enjoyment and connection in conversations where smiles were more frequent and intense. This has implications for fitness and health coaching, where creating a comfortable environment can encourage clients to open up about their goals, challenges and even insecurities.

Moreover, these findings reinforce the idea that clients might respond differently based on gender dynamics. For instance, same-sex client–trainer pairs might experience smoother rapport-building if both engage in frequent and responsive smiling. In mixed-sex pairs, trainers might need to actively smile more to ensure clients feel as engaged and connected.

Smiling can also be used with other nonverbal communication skills, such as mirroring, to further the development of rapport and trust. Mirroring involves subtly mimicking behavior during communication by imitating each other’s speech and/or physical behaviors is a way to feel connected and often occurs naturally as a part of human nature. Examples of mirroring can include:

• Increasing or decreasing the speed of speech
• Leaning backward or forward depending on what the client is doing
• Sitting or standing the way a client is sitting or standing

Mirroring can also be done verbally by repeating a phrase back to a client and by using the same words a client uses to describe things.

Applying These Findings: Practical Tips for Health Coaches and Exercise Professionals

As a health and exercise professional, being intentional about smiling can enhance client interactions and foster a supportive training environment. Here’s how to implement these findings in practical ways to strengthen client relationships and improve client satisfaction:

1. Use smiling as a tool to break the ice.

Many clients, especially new or returning clients, may feel nervous during initial consultations or assessments. Smiling at the beginning of these sessions can help clients feel more at ease. For instance, if a client seems hesitant to discuss their goals or concerns, a warm smile paired with open body language may encourage them to share more openly. This is particularly valuable for clients who might be intimidated by the setting or unsure of what to expect from their fitness journey.

2. Increase engagement with clients during workouts.

The study demonstrated that when one person smiles more, the other is likely to respond similarly, creating a loop of positivity. You can use this insight during workouts by smiling and providing encouraging feedback, especially when clients are performing challenging exercises. For example, a genuine smile paired with positive reinforcement like, “You’re doing great—keep it up!” can boost a client’s confidence and help them associate their workout with a positive experience.

3. Adapt smiling intensity for each client.

Understanding each client’s personality and comfort level is key. The study suggests that the impact of smiling might vary across gender dynamics, with same-sex interactions leading to stronger synchronized responses. This could mean that some clients may feel more comfortable with high levels of expressiveness, while others might prefer a more moderate approach.

For example, clients who exhibit a reserved personality may feel more comfortable with a restrained yet friendly approach. A small smile or nod may be all that’s needed to acknowledge their efforts without overwhelming them. For clients who are more outgoing or expressive, matching their level of enthusiasm with more frequent smiles and positive expressions can build camaraderie and energy in health coaching and exercise sessions.

4. Use smiling to gauge and adjust rapport.

During conversations, a lack of reciprocal smiling from a client might indicate that they are feeling uncomfortable or disengaged. If you notice a client is not responding to your smiles or seems tense, this could be a cue to adjust your approach. Consider asking open-ended questions to uncover if there’s something they’re feeling uncertain about, or offer them more autonomy in the workout design to make them feel more comfortable.

Furthermore, the study’s findings on the “emotional boost” that comes from smiling indicate that you can use smiles as an informal feedback tool. When clients respond with increased smiling, it’s a signal that they feel positive and engaged. This feedback can help you fine-tune your coaching style on the spot, making your approach more client-centered and responsive.

5. Encourage clients to smile during social interactions.

For clients who participate in group classes or fitness activities that involve social interaction, encourage the use of smiling as a way to create community and connection. Smiling can also enhance the social aspect of group workouts, which is often an essential motivator for many clients. Consider starting group sessions with a quick icebreaker or team activity that encourages everyone to share a smile and a few laughs, helping clients to relax and bond with each other.

Smile-driven Rapport as a Key Factor in Client Retention

As shown in the study, the positive feedback loop created by smiling fosters interpersonal connections and improves the quality of the interaction itself. This is essential in building rapport—a crucial factor in client retention. Clients who feel emotionally connected and supported by you are more likely to adhere to their exercise regimen, trust in your guidance and continue returning for sessions.

By using smiling as a tool to reinforce a welcoming and motivating environment, you can strengthen the professional–client bond and positively impact your clients’ experiences. “Smiling during a conversation creates warmth and can lead to a better interpersonal relationship,” says Dr. Otaka. Such connections are the foundation of a supportive and effective training and/or coaching experience, enabling clients to feel valued, encouraged and ready to tackle their health and fitness goals.

Chris Gagliardi, MS, ACE Scientific Education Content Manager, finds this research particularly interesting and recalls his days of working as a telephonic health coach. “My supervisor at the time encouraged all the coaches on her team to keep a mirror at their desk to check for smiles. She would tell us that even though your client on the other end of the phone can’t see you, they can tell if you are smiling or not. They can tell if you are happy and enjoying your time with them. I believe there was truth in this thinking and that even seeing myself smile in a mirror would help to set the stage for effectively working with clients.”

Final Thoughts

While seemingly simple, the act of smiling is backed by significant psychological and physiological benefits that can improve rapport, increase client satisfaction and boost the overall atmosphere of a fitness environment. As a health coach or exercise professional, recognizing the power of a genuine smile and applying it thoughtfully within your sessions can transform the client experience. Whether in one-on-one coaching or group settings, smiling is a powerful tool for cultivating a positive, inclusive and supportive environment—making clients feel seen, supported and motivated to achieve their goals.