Learn every lift
in 3D.
Free workout guides you can rotate to check your form from any angle, with the working muscles highlighted, plus calculators for your calories, protein, and one rep max.
3D Workouts
Gym exercises animated in 3D. Rotate them to check your form from any angle.
Barbell Back Squat
A foundational lower-body lift. With a barbell across your upper back, you sit your hips down between your heels and stand back up.
View in 3D →Kettlebell Goblet Squat
A beginner-friendly squat. Holding a kettlebell at your chest keeps your torso upright and makes it easier to sit deep between your heels.
View in 3D →Romanian Deadlift
A hip hinge for the hamstrings and glutes. With soft knees and a flat back, you push your hips back and lower a barbell down your thighs to about knee height.
View in 3D →Barbell Deadlift
The classic full-body pull. With a flat back and the bar against your shins, you stand up with a loaded barbell from the floor, driving through your legs and hips.
View in 3D →Dumbbell Lunge
A split-stance leg exercise for the quads and glutes. Holding dumbbells at your sides, you lower your back knee toward the floor and drive back up through your front foot. This is the stationary version, with your feet planted.
View in 3D →Standing Calf Raise
A simple bodyweight move for the calves. Standing tall, you rise up onto the balls of your feet as high as you can, then lower your heels slowly back to the floor.
View in 3D →Barbell Bench Press
The classic chest builder. Lying on a flat bench, you lower a barbell to your lower chest with your elbows tucked, then press it back up over your shoulders.
View in 3D →Dumbbell Bench Press
A flat-bench chest press with a dumbbell in each hand. Each arm works on its own, and the hands can travel a little further than with a barbell.
View in 3D →Incline Dumbbell Press
A chest press on a bench set to a low incline, which shifts more of the work to the upper chest and front of the shoulders.
View in 3D →Push-Up
The classic bodyweight chest exercise. Holding your body in one straight line, you lower your chest toward the floor and push back up.
View in 3D →Dumbbell Fly
A chest isolation move on a flat bench. With a slight, fixed bend in your elbows, you open your arms in a wide arc and hug the dumbbells back together over your chest.
View in 3D →Cable Crossover
A cable chest fly. Standing between two high pulleys, you sweep the handles down and together in front of your hips in a wide hugging arc.
View in 3D →Parallel Bar Dip
A bodyweight push for the chest and triceps. Supported on two bars, you lower your body by bending your elbows, then press back up to straight arms.
View in 3D →Pull-Up
The classic bodyweight back exercise. Hanging from a bar with an overhand grip, you pull your chin up over the bar and lower yourself back down.
View in 3D →Barbell Bent-Over Row
A heavy compound pull for the whole upper back. Hinged forward with a flat back, you row a barbell from arm's length up to your lower ribs.
View in 3D →One-Arm Dumbbell Row
A single-arm back exercise braced on a bench. With your torso flat, you row a dumbbell from arm's length up beside your waist.
View in 3D →Inverted Row
A bodyweight row under a bar set at about waist height. Holding your body straight like a plank, you pull your chest up to the bar.
View in 3D →Lat Pulldown
A cable machine pull that trains the same muscles as a pull-up. Seated with your thighs braced, you pull a wide bar down to your upper chest.
View in 3D →Seated Cable Row
A seated cable pull for the middle of the back. With your feet braced and torso tall, you row a close-grip handle to your stomach.
View in 3D →Barbell Overhead Press
The standing strength test for the shoulders. You press a barbell from the front of your shoulders to straight arms overhead, moving your head out of the way as it passes.
View in 3D →Resistance Band Pull-Apart
A simple upper-back and rear-shoulder exercise. Holding a band at arm's length, you pull it apart until it touches your chest.
View in 3D →Dumbbell Biceps Curl
The classic arm builder. Standing tall with your elbows at your sides, you bend at the elbow to lift the dumbbells toward your shoulders.
View in 3D →EZ-Bar Curl
A biceps curl with an angled bar. The EZ bar's bends put your wrists in a more natural, half-turned position than a straight barbell.
View in 3D →Dumbbell Triceps Kickback
A single-arm isolation move for the triceps. With your upper arm pinned alongside your torso, you straighten the elbow against the dumbbell's weight.
View in 3D →Cable Triceps Rope Pushdown
A cable isolation move for the triceps. With your elbows pinned at your sides, you press a rope down until your arms are straight and spread the ends apart.
View in 3D →Forearm Plank
A core hold. Resting on your forearms and toes, you keep your body in one straight line from head to heels for as long as you can hold good form.
View in 3D →Fitness calculators
Calories, protein, body composition, and strength numbers in seconds.
TDEE Calculator
Estimate your Total Daily Energy Expenditure and see calorie targets for maintenance, weight loss, or weight gain. Supports both metric and US units.
Open calculator →BMR Calculator
Estimate your Basal Metabolic Rate with the Mifflin-St Jeor, Harris-Benedict, and Katch-McArdle formulas, and see your calories at each activity level.
Open calculator →Macro Calculator
Turn a daily calorie target into grams of protein, carbs, and fat. Balanced, high-protein, low-carb, low-fat, or your own custom split.
Open calculator →Protein Intake Calculator
Find how much protein you need a day for your weight and goal, from building muscle to losing fat, and how much to eat at each meal.
Open calculator →Calories Burned Calculator
Estimate the calories you burn walking, running, cycling, swimming, lifting, and 30+ other activities from your weight and workout time.
Open calculator →Weight Loss Timeline
See when you'd reach your goal weight at a given pace, or what pace a target date needs, with the daily calories each plan takes.
Open calculator →BMI Calculator
Calculate your Body Mass Index from height and weight and see which category it falls into. Supports both metric and US units.
Open calculator →Ideal Weight Calculator
See the healthy weight range for your height, plus the Robinson, Miller, Devine, and Hamwi ideal body weight formulas. Metric and US units.
Open calculator →Body Fat Calculator
Estimate body fat percentage with the U.S. Navy tape-measure method, and see your fat mass, lean mass, and category. Supports metric and US units.
Open calculator →Heart Rate Zone Calculator
Work out your five training heart rate zones from your resting and max heart rate, using the Karvonen heart rate reserve formula.
Open calculator →Running Pace Calculator
Calculate pace, finish time, or distance from the other two, in km or miles, with speed and an even-split table. Presets for 5K to marathon.
Open calculator →One Rep Max Calculator
Estimate your one-rep max from a set of reps, and get training weights for every percentage from 65% to 100% of your max.
Open calculator →Barbell Plate Calculator
See exactly which plates to load on each side of the bar for any target weight, in kg or lb, using only the plates your gym has.
Open calculator →Reaction time
How fast are your reflexes? Try the quick test, then take a full test for an average over several rounds.
Test your reaction time
Tap when the box turns green · 3 rounds · about 15 seconds
Articles
The science behind training, nutrition, and the tools, in plain language.
Heart Rate Training: The Science of Zones and the Karvonen Formula
How heart rate reflects exercise intensity, where the Karvonen formula and “220 minus age” came from, what research says about training mostly easy, and how to find your own zones.
Read article →Pacing Strategy: The Science of Running Your Best Race
Why even pacing beats a fast start, what world records reveal about how the best runners spread their effort, how the marathon got its odd distance, and how to plan your own splits.
Read article →Protein, Carbs, and Fat: The Science of Macronutrients
What each macronutrient does, where calorie counts came from, how much protein you really need, and what large trials say about low-fat versus low-carb diets.
Read article →Measuring Body Fat: What the Tape, the Scale, and the Scanner Tell You
Why BMI misses so much, how body fat is measured — from underwater weighing to DEXA scans and the Navy tape method — how accurate each method is, and what a healthy range looks like.
Read article →Why Weight Loss Slows Down: The 3,500-Calorie Rule and Your Metabolism
Where the 3,500-calorie rule came from and why it overpromises, how metabolism adapts as you lose weight, whether fast or slow loss is better, and what helps people keep weight off.
Read article →Progressive Overload: The Science of Getting Stronger
How muscles adapt to lifting, how an army doctor turned heavy lifting into medicine, heavy versus light loads, how fast to add weight, and why strength training pays off for health.
Read article →The Science of Reaction Time: Why Milliseconds Matter
What really happens between seeing or hearing a signal and moving, why we react faster to sound than to light, how reaction time changes with age and sleep, and whether you can train it.
Read article →Smooth Pursuit: How Your Eyes Follow a Moving Target
The science of smooth pursuit eye movements — the brain circuits behind them, a century of research from Raymond Dodge to modern sports vision, and what tracking practice can realistically do for you.
Read article →Peripheral Vision and Visual Attention: Seeing More Than You Look At
Why only a tiny patch of your vision is sharp, how saccades and attention fill in the rest, and what research on the useful field of view and multiple object tracking says about training awareness.
Read article →The Schulte Table: The Science of Visual Search and Focus
Where the Schulte table came from, what visual search science says about finding numbers in a grid, how it relates to clinical attention tests, and an honest look at its link to speed reading.
Read article →Working Memory: How Much Can Your Mind Hold at Once?
The science of short-term and working memory — from Miller’s magical number seven to the Corsi block test — plus what brain-training research really shows and how sequence games can help.
Read article →Mental Math: What Happens in Your Brain When You Calculate
How the brain represents numbers and solves arithmetic, a short history of mental calculation from the abacus to human computers, and the real benefits of building arithmetic fluency.
Read article →Box Breathing and 4-7-8 Breathing: The Science of Slow Breathing
How slow, structured breathing affects your heart, nervous system, and mood — the physiology, the history from pranayama to military training, and what clinical studies actually show.
Read article →Brain & eye training
Short drills for focus, eye tracking, memory, and breathing.