“Yinner partnership ensures that people are fit for work and ready for the future.“
Atika Bouz, Projectmanager Gemeente Amsterdam
More health.
We guide people toward their goals through a blend of human training & coaching, data insights, and AI-powered performance support – across organizations and sports.
Human Coaching & Training
In-person training & coaching throughout the journey, integrating education, skill building, purpose discovery, and mindset coaching—either 1:1 or in group sessions.
AI-Coach Assistant
24/7 personalized coaching through our platform. Secure, private, personal and fully tailored to your journey whenever you need it.
Wearable & body informed data
An advanced medical wearable that provides insights into your HRV, burnout score, autonomic nervous system, sleep quality and other health data.
For sports
High performance starts by being the best version of yourself
For elite athletes, coaches and sport organizations
Yinner for Athletes
At Yinner, you are at the center. We guide you on your personal journey to sustainable peak performance, with a powerful mix of human coaching, continuous AI coaching, and insights from your wearable. This means you are supported every day to train smarter, recover better, and perform sustainably.
Yinner helps you to get the best out of yourself. By knowing the buttons to turn on to unlock your full potential. Both for your athletic capabilities and your resilience and energy status. After the program, you have the power to shape your own success and take control of your performance and career, fully aligned with your ambitions and goals.
Yinner for Coaches
Bring Out the Best in Every Athlete
Great coaching is not just about training harder. It’s about developing the athlete behind the performance. At Yinner, we help coaches create sustainable peak performance through one integrated ecosystem. Technical and tactical skills, health and wellbeing, mental strength, recovery, environment and strategy work together not separately.
Coach the complete athlete with human & tech solutions
An athlete can have world-class skills, and still underperform due to a fragile support system, low recovery, stress, pressure, lack of focus. Our approach helps coaches to:
- understand what truly drives performance in each athlete
- recognize early signs of overload, stress, or mental fatigue
- build resilience and self-regulation under pressure
- support recovery, energy management, and long-term health
- create a high-performance environment where athletes thrive
For organisations
More health, better performances, higher quality of life starts with being your best self
For employees, leaders and teams
Yinner for corporate athletes
Get the best out of yourself
Take a fresh approach to employee performance. The pressure is on and how are your employees handling it? They need to reach their personal peak and sustain it every day and every year on their journey to success.
Our solutions help employees strengthen their resilience and develop new capabilities that support sustainable health, effectiveness, and long-term results.
We guide them through a combination of human expertise, AI-powered insights, and data-driven coaching and training within our proven framework.
Yinner for Leaders
Unlock the best in others
Great leadership is about understanding what truly drives people – and knowing which buttons to turn on to help people perform, grow, and thrive. At Yinner, we know that leading others is a performance discipline.
Just like elite athletes, professionals perform best when their development is approached holistically: skills, strategy, environment, wellbeing, and mindset all work together. That’s how we support leaders in learning how to bring out the best in others sustainably.
Our approach helps leaders to:
- recognize what is really happening beneath performance
- understand the individual needs of each team member
- coach with precision instead of assumptions
- create the conditions where people can flourish
- strengthening resilience and self-regulation
- building capabilities and mental sharpness
- improving energy, focus, and recovery
Yinner for Learning & Development
Learn the skills to lead L&D
We are a leading authority in building skills in mastering and leading sustainable L&D performance. We integrate resilience, capabilities and performance into your leader, manager & staff training.
Our Masterclass include: The Future of L&D
Let's connect- Harmonizing Human Expertise with AI coaching
- AI in Coaching
- Enhanced insights trough AI & Wearables
- The Human element in Coaching
- Learning journeys and real time personalization at scale
- The Blending of AI and Human Coaching
- Biometric & Energy Intelligence
The Yinner method
At Yinner, we support you constantly on your path to your end-goal. From where you are now to what you want to achieve in the future.
We use powerful structures and holistic principles from elite sports that are universally applicable to people.
With a combination of human & tech real-time performance coaching, data-driven based on biometric data.
Sustainable performance starts with our holistic performance equation, real-time readiness checks, goal setting and personalized guidance to improve your capabilities, resilience and energy on your journey.
Where we stand for
Young at Heart
Open-minded, curious, energetic, and continuously developing
Inner Drive
Strong inner drive for growth and performing at your best
Relationship Oriented
Focused on building strong relationships and collaboration
Results Driven
Committed to achieve measurable and sustainable results
Evidence-based approach
Yinner: proven concept for business and sports
Automate and remove unnecessary training & coaching tasks
Focussing on meaningful, high-value coaching
Better health. Better performance. Better quality of life. Less absenteeism and burnout. More vitality.
OUR CLIENTS
What People Say
“Companies should adapt to the future needs of changing job roles. Yinner can help you with this.”
Martijn Willemsen, Field Sales trainer & coach Coca-Cola
“If we want to be the business of tomorrow, we must stop traditional car leasing. We use Yinner to develop for futures roles.”
Marjolein Groen, HR business partner Athlon
“What Yinner does is develop and prepare people. The aim is to prepare people for new roles and be ready and fit for the future.”
Lucas de Vries, Customer service NRC Handelsblad
“Yinner truly knows what a company needs and where the strengths of a person lie. In this way, they can create the best match from a human point of view.”
Yoeri van Alteren, CEO Change INC.
Our Mission
Yinner helps professionals achieve sustainable peak performance by combining AI based elite coaching and high- end biometric insights and personalized guidance.
Our Team
I’m Coert-Jan Tomassen, Founder & CEO of Yinner. I help professionals and teams elevate their performance in a sustainable way - drawing on proven principles from elite sports. My purpose is to make the insights and methods I’ve learned at the highest level accessible to everyone, so more people can unlock their potential faster, with more focus, energy, and impact.
I am Ellekijn van Vliet, Operational Lead and Coach at Yinner. My passion is guiding people in strengthening their energy and optimizing their performance, based on the belief that peak performance starts with a healthy balance between body and mind. From personal experience, I understand what it feels like when your energy declines and life feels heavier and how you can gradually regain strength and direction, step by step. My goal is to help clients grow sustainably not only during their journey with us, but also in the long term — enabling them to remain vital, resilient, and self-aware for life so they become the best version of themselves.
I am Jelle van Vliet, and my role within Yinner is Business Strategy & Planning.
I am a versatile, people-oriented and entrepreneurial leader with extensive national and international experience in driving sustainable growth through commercial, operational, innovative, and digital transformation. Guided by a clear sense of purpose, I connect strategy and execution in a natural and agile way within Yinner.
With a strong focus on growth, acquisitions, innovation, operational excellence, digitalization, and international expansion I build lasting value for people.
I am a versatile, people-oriented and entrepreneurial leader with extensive national and international experience in driving sustainable growth through commercial, operational, innovative, and digital transformation. Guided by a clear sense of purpose, I connect strategy and execution in a natural and agile way within Yinner.
With a strong focus on growth, acquisitions, innovation, operational excellence, digitalization, and international expansion I build lasting value for people.
I believe that real progress begins when we pay attention to how people feel, think, and grow — and when there is space for reflection, understanding, and conscious choices. To me, innovation is not a driving force, but a supportive one: technology should empower people, not replace them. In my work, I strive to create experiences that feel personal, grounded, and empowering. I see innovation as a means to reduce complexity, not to take control. My goal is to help people gain clarity, strengthen their own decision-making, and take steps that authentically align with who they are. The greatest impact occurs when people remain in control, with technology operating in the background — respecting autonomy, boundaries, and individuality.
Contact our team
Tell us about your needs and our team will help you to get there.
Ellekijn van Vliet
Performance coach
"*" geeft vereiste velden aan
Ellekijn van Vliet
Performance coach
