Relativity for Runners

Training that adapts to your reality

Weather. Terrain. Fatigue. Recovery. Your training plan should understand them all.

Today's Workout
Optimized
8.5
miles
7:45
target pace
-8%
heat adj.
78°F
65% humidity
Moderate heat

Intelligent by design

Every feature is built to help you train smarter, recover better, and perform at your peak.

Weather-Aware Engine

Training plans that adapt to real-time conditions. Heat, humidity, wind, and sun exposure all factor into your prescribed effort.

Scientific Load Tracking

TRIMP-based load management with acute-to-chronic workload ratios. See exactly how your fitness and fatigue are trending.

Precision Elevation

Grade-adjusted pace using digital elevation models. Know your true effort on any terrain, not just what your GPS guessed.

Nutrition Intelligence

Fueling recommendations based on workout intensity and duration. Personalized carb and hydration guidance for every session.

Privacy-First Design

Your training data stays yours. No selling to third parties, no ads, no compromises. You control your information.

Performance-First

Fast, responsive, and reliable. No bloated features or slow interfaces. Just the tools you need to train smarter.

See it in action

Interactive demos that show how EinsteinFit adapts your training to real-world conditions.

Conditions Intelligence

See how conditions affect your workout

78°F
50°F110°F
50%
0%100%
5 mph
Calm30 mph
Sun Exposure
Safe
-1%

intensity adjustment

Mild heat. Minor pace adjustment recommended.

For demonstration purposes only. Not medical or coaching advice.

Real-Time Adaptation

How your workout responds to changing conditions

Auto-advancing

3-Provider Weather Reliability

Real-time triangulation from multiple sources

Cold (40°F)72°FHot (100°F)
Weighted Consensus
0°F
Temperature
0%
Humidity
0 mph
Wind
0% Confidence

EinsteinFit triangulates weather from multiple providers, weighting by reliability and latency to deliver the most accurate conditions for your training adjustments.

Weather-Adjusted Calories

See how conditions affect your energy expenditure

45 min
Intensity
72°F
50%
200 ft
549
total calories
Base: 540 cal
Heat: +4 (+1%)
Humidity: +0 (0%)
Elevation: +5 (+1%)
14 oz
recommended hydration
+2% weather adjustment

Estimates based on a 160 lb runner. Actual values vary by individual metabolism, fitness level, and terrain.

Built with rigor

Training intelligence grounded in science, refined through testing, and proven in practice.

Scientific Foundation

Based on peer-reviewed exercise physiology research

Real-Time Data

Environmental conditions updated throughout the day

Continuous Improvement

Algorithms refined based on real-world outcomes

“Built with guarantees. Tested with rigor. Shipping excellence.”

Frequently Asked Questions

Everything you need to know about training with EinsteinFit.

EinsteinFit pulls real-time weather data from multiple providers and adjusts your workout intensity based on temperature, humidity, wind, and sun exposure. Hot and humid conditions mean slower paces; cool and dry conditions let you push harder.

TRIMP (Training Impulse) is a scientifically validated method for quantifying training load based on duration and intensity. We track your acute (7-day) and chronic (28-day) training loads to help you optimize fitness gains while avoiding overtraining.

We use Digital Elevation Models (DEM) to calculate true elevation gain, not just what your GPS estimates. This means more accurate grade-adjusted pace calculations, especially on hilly terrain where GPS can be off by 30% or more.

Absolutely. We don't sell your data to third parties, we don't show ads, and you control what you share. Your training data stays yours. You can export or delete your data at any time.

Currently we focus on running and cycling, with plans to expand to swimming, hiking, and other endurance sports. Our weather and load tracking algorithms are sport-specific for maximum accuracy.

EinsteinFit offers a free tier with core features. Premium features like advanced analytics, historical weather data, and personalized nutrition guidance are available with a subscription. See our pricing page for details.

Still have questions? Contact support

Ready to train smarter?

Join athletes who are done guessing and ready for training intelligence that adapts to reality.

or stay updated

No spam. Unsubscribe anytime. Privacy Policy