Many fitness apps still rely on BMI as a primary indicator of health. That’s a problem if you train for strength. The metric doesn’t account for muscle mass, bone density, or body composition. If you’re lean but strong, you might still get flagged as “overweight” or “obese” by default settings.

That creates confusion, especially for women who lift. Progress gets misclassified. Confidence takes a hit. And the algorithm keeps nudging you back toward weight loss instead of performance.

Why Fitness Apps Still Misread Progress

Let’s get this out of the way: BMI was never designed for individual assessment. BMI is a height-to-weight ratio developed in the 1800s, useful for population data but not for personal health insights. Yet many wearables, dashboards, and gym platforms still use it as a core calculation.

This results in a misread for anyone who has added lean muscle mass. Coaches know the issue well. A client gains ten pounds of lean tissue, drops two pant sizes, and the app still calls them “at risk.”

The default interpretation? Lose weight. Even if what they gained was functional, protective, and metabolically active.

Women Get Hit Twice

For women, the tech bias cuts deeper. Muscle gain already comes with outdated myths and social friction. Add a dashboard that penalises your progress, and it reinforces old fears. This is where most fitness apps fail to meet their users’ needs. Instead of reflecting performance, strength gains, or improved posture, they loop back to weight loss as the assumed goal.

Coaches working with women in perimenopause, strength cycles, or recovery phases often need to explain why the app isn’t a reliable guide. Data should drive progress, not anxiety.

The Economics Behind the Flawed Tech

Why haven’t the big apps updated their metrics? For a fairly straightforward reason: Simplicity and scale. 

BMI is easy to calculate and fits neatly into corporate reporting, insurance categories, and algorithmic sorting. But it’s not made for nuance. As strength-focused users become a larger market segment, the disconnect will only widen.

This is also why independent coaches and clinics with better measurement tools have a competitive edge. They don’t need to rely on outdated software. They can educate and program with clarity.

Better Metrics: What To Track Instead

If you want your tech to match your training, here’s what to look for:

• Body circumference changes: Waist-to-hip ratio, limb measurements, and belt notch counts give more context than total weight alone.
• Performance data: Are you lifting heavier, recovering faster, or holding better positions under load? That’s health in motion.
• Biofeedback markers: Sleep quality, hunger cues, mood, and digestion often improve before the scale changes.
• Blood markers: If the app integrates with lab data, you’ll gain a clearer view of your health status, beyond visual cues or scale weight.
• Photos over time: Visual tracking reveals muscle definition, posture changes, and fat loss that the scale may miss.

How Coaches Can Help Clients Reframe

When a fitness tracker mislabels your client, the solution isn’t to throw out the data, but to reframe how that data is interpreted. Reframing client mindsets all starts with education.

Show your clients what their bodies are doing well. Point out performance wins. Reinforce non-scale victories. If they deadlift their bodyweight, sleep through the night, or set clearer boundaries at work, that speaks volumes.

Teach them what real strength progress looks like, even if the graph doesn’t show it.

Final Thoughts

Fitness tech should help users get stronger, not second-guess their progress. If the tool you’re using still treats muscle like a problem, it might be time to reassess what metrics serve your goals.

Strong bodies don’t always shrink. They adapt, hold shape, and carry more muscle than most charts expect. Coaches who are aware of this can guide their clients through the noise, one reframe at a time.

About Robert James Rivera
Robert is a full-time freelance writer and editor specializing in the health niche and its ever-expanding sub-niches. As a food and nutrition scientist, he knows where to find the resources necessary to verify health claims.