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Artificial Intelligence

Analysis of body composition by artificial intelligence

Trainer Connect is the first personal trainer app in the world with AI-powered body composition analysis from a photo. Take the body assessment photos and the AI estimates body fat percentage, somatotype, posture, and muscle asymmetries in seconds — no bioimpedance, no skinfold caliper, with the accuracy of the world's most advanced multimodal models.

How AI-powered fitness assessments work

In 4 simple steps, right inside the app, you turn a traditional body assessment into a complete visual analysis powered by artificial intelligence.

1

Client authorizes

The student records consent in the app (once), as required by LGPD. They can revoke it at any time under "Profile → AI Analysis."

2

Trainer takes the photos

During the assessment, take front, back, and side photos. Workout clothes, neutral background, even lighting — the better the photo, the more accurate the analysis.

3

AI analyzes in seconds

The Claude Sonnet model (by Anthropic) processes the images and generates estimates for body fat %, lean mass %, somatotype, posture, and asymmetries.

4

Trainer reviews and saves

Values appear editable so the personal trainer can review them. Clinical interpretation is always up to the professional. Everything is logged in the student's assessment.

What AI measures in your client

A complete visual analysis that goes far beyond a number on the scale. Everything a personal trainer needs to prescribe evidence-based training.

Why does AI body analysis matter?

Traditional body assessments depend on expensive equipment (segmental bioimpedance, DEXA, skinfold calipers) or manual measurements that vary widely between examiners. For trainers working online, in gyms without the right equipment, or offering remote coaching, equipment barriers have always limited continuous tracking of a student's body composition.

AI-powered visual analysis changed that game. Multimodal models like Claude Sonnet, by Anthropic, were trained on millions of images and can identify subtle anatomical markers: fat tissue distribution, muscle definition, body segment proportions, and postural patterns. This enables them to generate useful body composition estimates from standard physical assessment photos.

It's not a substitute for high-precision DEXA or bioimpedance scans — it's a practical, accessible complement. Trainers can run multiple analyses throughout the month to track a client's progress between formal clinical assessments, spot trends (losing lean mass? gaining belly fat?), and adjust training more quickly.

Who benefits most

  • Online coaching personal trainers — for those without physical access to the student, who used to rely only on a scale and photos.
  • Gym instructors — for those who want to offer high-value fitness assessments without investing in expensive equipment.
  • Sports coaching trainers — for those who need to keep up with dozens of students quickly.
  • In-home service professionals — for those who can't fit a bioimpedance scale in their bag.

Privacy, compliance, and security

Body analysis requires photos. Photos require responsibility. Trainer Connect was built with privacy by design.

Client's express consent (LGPD)

AI analysis only runs after the student explicitly authorizes it, logged in the app with date, time, and consent version. The trainer can also record consent on the student's behalf (with their agreement, in person). The student can revoke consent at any time under "Profile → AI Analysis."

Signed temporary URL

Photos aren't sent to the AI in bulk. Each analysis generates signed URLs with a short expiration, used exclusively for the Anthropic request. Once processing is done, the links expire automatically.

Anthropic's zero data retention

Anthropic maintains a zero retention (zero data retention) for enterprise clients via API: images are neither stored nor used to train models. All processing is ephemeral.

Personal trainer always in control

The values generated by AI are editable suggestions. The trainer reviews each field before saving it to the assessment. Clinical interpretation and the final prescription are always the responsibility of the professional with proper professional registration.

Frequently asked questions about AI body analysis

How does AI estimate body fat percentage from a photo?
Trainer Connect's AI (Claude Sonnet, by Anthropic) is a multimodal vision model trained on millions of images. It analyzes proportions, muscle definition, fat tissue distribution, and visible anatomical markers in body assessment photos to generate a body fat percentage estimate. It's a visual estimate — it doesn't replace a DEXA scan or high-precision bioimpedance, but it's practical, instant, and useful for ongoing tracking.
What kind of photos do I need to submit for AI body analysis?
Ideally full-body photos of the client from three angles: front, back, and side. Use form-fitting workout clothes (top + shorts or leggings), even lighting, a neutral background, and a natural stance (standing, arms relaxed at the sides). The higher the photo quality, the more accurate the AI's analysis.
Does the AI replace bioelectrical impedance and skinfold calipers?
It doesn't replace — it complements. AI-based visual analysis is a practical, low-cost tool for ongoing tracking, especially useful in online coaching. For clinical precision, methods like DEXA and segmental bioimpedance remain the gold standard. The advantage of AI is being able to run multiple assessments throughout the month at no extra cost, tracking progress over time.
Does the AI comply with LGPD and respect student privacy?
Yes. The analysis only runs after the student's explicit consent, recorded in the app. Photos are sent via a signed temporary URL to Anthropic, solely at the moment of analysis. Anthropic maintains a zero data retention policy — images are never used to train models. Students can revoke consent at any time under "Profile → AI Analysis". See also our Terms of Service, clause 8.1.
Who can use it: personal trainer or client?
The analysis is run by the trainer, within the student's body assessment screen. The student authorizes it (consent), the trainer takes the photos during the assessment, the AI generates the values, and the trainer reviews them before saving. All clinical interpretation remains the professional's responsibility.
Which plan includes AI-powered body analysis?
AI-powered body analysis is included in all paid Trainer Connect plans, with a monthly quota: Starter (5 assessments/month), Pro (20), Elite (50) and Unlimited (unlimited). The free plan doesn't include AI analysis.

Modernize your fitness assessment today

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