How Tonal Uses Markerless Motion Capture from Theia3D to Scale Biomechanics Research and Personalize Strength Training

Summary

Tonal’s biomechanics team uses Theia3D markerless motion capture to accelerate research, validate motion models, and power features like Smart View. Learn how they’ve streamlined data collection, scaled biomechanics across participants, and turned lab insights into real-time, personalized strength training.

Partner: Tonal
Team Lead: Steven Hirsch, Staff Data Scientist
Focus Area: Biomechanics & Exercise Science
Solution: Theia3D Markerless Motion Capture with Vicon
Key Benefits: Accelerated R&D cycles, biomechanics at scale, seamless lab-to-product integration, scalable data collection

Innovating Fitness with Data: Why Tonal Invests in Biomechanics at Scale

Tonal is redefining strength training through a blend of science, smart hardware, and personalized coaching. As a connected strength system powered by AI, Tonal adapts to each user’s abilities and goals in real time - using force sensors, velocity data, and motion analysis to drive smarter workouts.

At the center of this innovation is a deep commitment to biomechanics research. Tonal’s internal R&D lab collects and analyzes human movement data to power Smart View (their in-app feedback tool), test new models, and enhance training programs based on actual user behavior.

But high quality motion capture typically requires long setup times, complex calibration, and specialist operators. In a fast-paced R&D environment with limited athlete access, traditional marker-based systems just couldn’t keep up.

“We have limited time with participants. Theia3D was the only option that allowed us to collect high-quality motion data quickly and consistently - and still maintain the accuracy our research demands.”

- Steven Hirsch, Staff Data Scientist - Tonal

The Challenge: Fast, Repeatable Data Collection for Product Development

Tonal’s biomechanics team needed a motion capture solution that could:

Capture multiple participants back-to-back
Generate “ground truth” data
Fit into short research sessions (~30 mins max)
Provide robust and reliable data for user feedback models

Marker-based systems posed too many friction points - including setup time, sensitivity to calibration, and tedious post-processing. That left Tonal with a crossroads: looking for a research grade mocap solution that would seamlessly support the iterative nature of fast-paced product innovation.

The Solution: Markerless Motion Capture with Theia3D

To streamline R&D, Tonal adopted Theia3D as its primary lab-based motion capture system. With Theia3D, researchers can conduct full 3D biomechanical evaluations in minutes - without placing markers or managing complex rigs.

‍Key Benefits for the Tonal Team:

Rapid, Reliable Data Collection: Theia3D enables Tonal to collect high-quality motion data from participants in just 20-30 minutes - a 60-70% time reduction compared to traditional systems.
Efficient, Scalable Workflow: With batch processing and no need for markers, the team can run back-to-back sessions with minimal prep or post-processing time, allowing for greater subject throughput and faster iteration.
Validated Ground Truth Data for Model Training: Theia3D provides biomechanical data that serves as a reference point for training and validating Tonal’s own exercise models
Lab-to-Product Integration: Insights from Theia-powered research directly inform Tonal’s in-app features - enabling a faster path from scientific validation to user impact.

“Theia strikes the perfect balance between research-grade rigor and ease of use. It lets us focus on what matters most - collecting clean, high-quality data and translating it into better experiences for our users."

The Results: 3x Faster Research, Better Product Insights

Since implementing Theia3D Tonal has dramatically increased its research efficiency:

Comparison: Marker-Based vs. Theia3D Motion Capture at Tonal
Metric	Before (Marker-Based)	After (Theia3D)
Time per data collection	60–90 minutes	20–30 minutes
Participant throughput	1–2 per session	3–4 per session
Post-processing time	Manual, labor-intensive	Automated batch processing

This efficiency has allowed the team to scale their biomechanics research - analyzing more subjects, refining algorithms faster, and continuously improving Smart View’s ability to detect and coach form in real time.

“We used to spend more time cleaning data than using it. Now we batch process, dive right into analysis, and start building right away.”

Why It Matters: Unlocking Human Potential Through Smarter Strength Training

Tonal and Theia share a vision: bringing biomechanics out of the lab and into everyday training to unleash human potential. With Theia3D, Tonal’s team now has a fast, scalable motion capture solution that supports every stage of product development - from research concept to real-world, in-app experience.

Whether it’s validating force-velocity profiles, analyzing form at scale, or designing evidence-based training programs, Theia empowers Tonal to deliver lab-grade intelligence through a product that adapts to each user’s unique movement - helping people move better, train smarter, and reach their full potential.
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Ready to See How Theia3D Can Fit Into Your Workflow?

Book a demo to see how your team can scale up without sacrificing accuracy.

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