Science-backed calculators and movement analyzers designed to optimize your joint health, daily calorie burn, metabolic balance, and training periodization without guesswork.
Matches your heel drop (0mm to 12mm), rocker sole geometry, and foam density to specific conditions like plantar fasciitis, Achilles tendinopathy, and flat arches.
Calculates optimal turnover rates (steps/min) and stride length based on height and walking pace. Detects overstriding to reduce ground impact stress on shins and knees.
Calculates Basal Metabolic Rate (BMR) and daily energy burn via the clinically validated Mifflin-St Jeor formula. Provides targeted deficit and macronutrient distributions.
Estimates single-effort mechanical strength using submaximal rep sets with Brzycki and Epley equations. Generates intensity zones for hypertrophy and strength periodization.
Generates custom hourly feeding and fasting windows (16:8, 14:10, 18:6) synchronized with natural circadian rhythms, workout timing, and autophagy metabolic states.
Applies Compendium of Physical Activities MET ratings to calculate caloric expenditure based on body weight, walking speed, and treadmill incline angles.
Determines Zone 1 through Zone 5 aerobic and anaerobic heart rate training ranges using personal resting heart rate and Heart Rate Reserve (HRR).
Estimates total fluid requirements and sodium replenishment based on workout duration, ambient temperature, humidity, and individual sweat rates.
Evaluates EVA and TPU foam breakdown across mileage milestones (350–500 miles) to help walkers replace footwear before joint impact pain emerges.
Estimates body fat percentage, lean tissue weight, and fat mass using tape measurements of the neck, waist, and hips based on Naval Health Research equations.
Generic health calculators often use oversimplified rules of thumb. Keep Fit Health tools implement peer-reviewed equations, including Mifflin-St Jeor for basal metabolism, the Karvonen formula for cardiovascular training zones[cite: 1], and Brzycki submaximal algorithms for resistance training[cite: 1].
Physical fitness requires joint longevity. Our footwear and gait analyzers are specifically engineered to help walkers and runners manage heel-to-toe drop angles, match midsole cushioning to structural arch heights, and prevent overuse conditions like plantar fasciitis and Achilles tendinopathy[cite: 1, 2].
Every tool runs client-side inside your browser. No personal measurements, heights, weights, or lifestyle data are sent to external databases or stored on servers, giving you instant results with complete privacy.
