Staff Applied Scientist (Human Performance AI)

Who We Are

At Tonal, we know firsthand that too many hurdles stand between each of us and our fitness goals. Drawing on decades of research and a diverse team of experts, we have created the most intelligent strength training system available that makes working out more efficient, effective, and engaging. 

We are applying our collective knowledge and creativity to reimagine working out, leveraging hardware, software, video content, artificial intelligence and computer vision to help customers achieve their fitness goals.

 We're passionate about building products that help our customers thrive.

Overview
Tonal is looking for a Staff Applied Scientist (Human Performance AI) to help expand Tonal’s intelligence across movements, training modalities, and member goals. You’ll be joining a high-impact team at the intersection of machine learning, biomechanics, and product innovation, building algorithms that adapt workouts, enhance coaching, and personalize progression using the largest strength training dataset in the world. With millions of workouts collected across diverse users, and enriched by data from cameras, cable sensors, and external trackers, Tonal has a one-of-a-kind platform for real-world AI. 

This role will be instrumental in developing models that enable new modalities and movements, detect fatigue, predict performance, define new training metrics, and learn how to relate to effort, engagement, and outcomes. 

What You Will Do

• Design and build advanced machine learning models and algorithms that power personalized training, form feedback, and intelligent progression

• Analyze movement patterns to identify fatigue, inefficiencies, or injury risk using real-world sensor data

• Define new metrics for training effectiveness, effort, and performance beyond traditional volume or weight lifted

• Apply self-supervised and transformer-based learning methods to extract insight from unlabeled or minimally labeled data

• Prototype and productionize models that enhance Tonal’s coaching capabilities and member experience

• Collaborate with Sports Science, Product, and Software teams to bring new intelligent features to life

• Use analytics to validate model impact, guide feature design, and support continuous learning in deployed models

• Mentor teammates and help shape Tonal’s long-term data science and AI roadmap

Who You Are

• A self-driven machine learning scientist with experience owning applied AI projects end-to-end and a passion for building meaningful real-world products

• 7+ years of experience, or 5+ with a Master’s degree, or PhD with 3+ years of experience in applied machine learning or data science

• Strong background in modeling time-series, human motion, or physical sensor data (e.g. force, velocity, pose estimation)

• Proficient in Python, and familiar with ML frameworks like PyTorch or TensorFlow

• Experience working with large datasets in modern environments like Databricks or Snowflake.

• Strong communicator who thrives in cross-functional settings and can simplify complex models for a product audience

• Demonstrated ability to experiment rapidly, iterate thoughtfully, and deliver production-level code

Extra Credit

• Experience deploying ML models to real-time systems or edge devices

• Experience with transformer architectures or self-supervised learning

• Background in biomechanics, kinesiology, or sports science

• Interest in fitness, performance training, or personalized coaching

At Tonal, we believe that the unique and varied lived experiences of our teammates contribute to our overall strength. We don’t just appreciate differences, we celebrate them, and we always seek people that represent a wide variety of backgrounds. We’re dedicated to adding new perspectives to the team and designing employee experiences that contribute to your growth as much as you do to ours. If your experience aligns with what we’re looking for (even if you don’t check every single box), send us your application. We would love to hear from you!

Tonal is committed to meeting the diverse needs of people with disabilities in a timely manner that is consistent with the principles of independence, dignity, integration, and equality of opportunity. Should you have any accommodation requests, please reach out to us via our confidential email, accessibility@tonal.com. All requests will be addressed and responded to in accordance with Tonal’s Accessibility Policy and local legislation.