AI Workout App Dr. Muscle Launches New App, Saves $125,000 a Year by Replacing Developers with AI
Founder Dr. Carl Juneau describes a six-month rebuild using AI, reducing developer headcount by about half
Sheridan, WY, Jan. 05, 2026 (GLOBE NEWSWIRE) — Dr. Muscle, an AI workout app company, reduced software development costs by about $125,000 per year after shifting a significant share of coding and implementation work from human developers to AI coding assistants. The company is launching Dr. Muscle X, a rebuild of its flagship AI workout app, and is sharing what it learned about using AI to change how a small team ships software.
Dr. Muscle X AI Workout App
The catalyst was a hiring experience that reflected a controversial trend in remote work. A recently hired senior tech lead was discovered to be interviewing for multiple other positions on the job — part of what some have called the “overemployed” phenomenon. This was the moment Dr. Carl Juneau, the founder of Dr. Muscle, started asking a different question: not “How do we hire better?” but “What if we didn’t need to hire at all?”
Rather than continue hiring, the company tested whether AI tools could take on tasks that previously required additional headcount. Dr. Muscle said it now uses AI-powered tools for much of its day-to-day development work, while remaining team members focus on product decisions, quality assurance, and tasks that require human judgment.
“The question was not whether AI could help developers write code faster,” said Dr. Juneau. “It was whether a small company could redesign its workflow so fewer people were needed to ship and maintain a production app. For us, the answer was yes — but only with careful review.”
Dr. Juneau, who holds a PhD in Public Health, said he led the rebuild despite not being a career software engineer. In the company’s description of its workflow, AI systems generated and modified code in response to prompts, and the founder reviewed the output and integrated it into the product. The company said it also added automated testing and review checks to validate AI-generated changes.
Dr. Muscle said the rebuild produced measurable changes in both timeline and performance. Dr. Muscle X, released as a progressive web app, was completed in six months — work the company estimates would have required its original five-person development team over a year. In internal performance benchmarks, time to start a first exercise fell from 10.2 seconds to 4.1 seconds.
For the company, the rebuild was intended as a test of how AI-assisted development can affect small-business economics, not a change in training methodology. Dr. Muscle said its progressive overload algorithm, refined over nearly a decade, continues to drive workout recommendations. The rebuild focused on user experience and speed while keeping the underlying training logic consistent, the company said.
“Small companies feel constraints first — budget, hiring, and time,” Juneau said. “What surprised me was how quickly the bottleneck moved from writing code to verifying code. Once verification became the focus, the team could do more with fewer people.”
Dr. Muscle X is available in early access at x.dr-muscle.com. The timing aligns with January interest in fitness and training programs.
KEY FINDINGS FROM DR. MUSCLE’S AI WORKFORCE SHIFT
- Cost reduction: About $125,000 in annual savings (company estimate)
- Team change: Development headcount reduced by about half
- Delivery timeline: Six-month solo rebuild versus an estimated 12+ months with original five-person dev team
- Founder background: PhD in public health (exercise epidemiology); no formal computer science training
FREQUENTLY ASKED QUESTIONS
What does “replacing half the dev team with AI” mean? Dr. Muscle said routine coding, debugging, and implementation tasks that previously required additional developers were shifted to large language models and AI coding assistants. Remaining team members focus on product direction, quality assurance, and tasks that require human judgment.
Which AI tools were used? The company said it relied on Claude (Anthropic), ChatGPT (OpenAI), and AI-powered extensions for Visual Studio Code. In its workflow, the founder writes prompts, reviews AI-generated code, and integrates it into the product.
Is this approach replicable for other small businesses? Dr. Muscle said the approach may be most applicable to small product companies where leaders are willing to adopt AI-assisted workflows and where work can be verified reliably. The company has published a longer build write-up at dr-muscle.com/dr-muscle-x-built-with-ai/.
What is Dr. Muscle X? Dr. Muscle X is an AI workout app that generates personalized training programs using progressive overload and other evidence-based training principles. It is a rebuild of the Dr. Muscle app and is launching in January 2026 as a progressive web app in early access at x.dr-muscle.com.
ABOUT DR. MUSCLE
Dr. Muscle is a fitness technology company that builds training programs based on scientific principles. Founded in 2016 by Dr. Carl Juneau, PhD, the company said its users have completed hundreds of thousands of workouts using its software. More information is available at dr-muscle.com.
MEDIA CONTACT
Dr. Carl Juneau, PhD
Founder, Dr. Muscle
carl@dr-muscle.com
LINKS
- Dr. Muscle: https://dr-muscle.com/
- Dr. Muscle X: https://x.dr-muscle.com
- Build write-up: https://dr-muscle.com/dr-muscle-x-built-with-ai/
Dr. Muscle X AI Workout Program
