Written by Will Duru, BSc (Hons) Sport and Exercise Science, award-winning Personal Trainer with over 10 years of experience in strength training and optimising recovery.
Poor form is killing your gains. Every day in the gym, I see people performing exercises incorrectly—rounded backs during deadlifts, flared elbows on bench press, knees caving during squats. These mistakes don’t just limit progress; they lead to injuries that can derail your fitness journey for months.
This is why 12REPS features over 2,000 professional exercise videos—all performed and taught by certified personal trainers. Not generic animations. Not stock footage from random models. Real qualified personal trainers with years of hands-on coaching experience, showing you exactly how to perform each movement safely and effectively.
Two Types of Professional Video Content
12REPS doesn’t just give you one video per exercise—we give you comprehensive instruction through two distinct video formats:
1,500+ Exercise Demonstration Videos
Every exercise in our library includes a professional demonstration performed by certified personal trainers. These videos show the complete movement from multiple angles so you can see exactly what proper form looks like in action.
500+ Detailed Tutorial Videos with Muscle Highlights
This is where 12REPS truly stands apart. For the most important exercises, we’ve created detailed tutorial videos that go far beyond simple demonstrations. These comprehensive guides include:
- Step-by-step instructions: Personal trainers walk you through each phase of the movement, explaining exactly what to do at every stage
- Muscle highlight overlays: Visual graphics show you which muscles are being activated during each part of the exercise
- Multiple camera angles: See the movement from front, side, and back views to understand the complete pattern
- Common mistakes breakdown: Watch real examples of incorrect form and learn exactly what to avoid
- Progression and regression options: Learn how to modify the exercise for your current fitness level
These tutorial videos transform 12REPS from a simple workout tracker into a comprehensive education platform. You’re not just following exercises—you’re learning the science and technique behind proper training.
Why Professional Exercise Videos Matter
Most workout tracker apps treat exercise demonstrations as an afterthought. They licence generic videos, use basic animations, or rely on user-generated content. This approach fails because proper form isn’t one-size-fits-all, and understanding the nuances of each exercise requires expert knowledge.
When certified personal trainers demonstrate exercises in 12REPS, they’re drawing on years of experience coaching hundreds of clients. They know the common mistakes beginners make. They understand the subtle cues that make the difference between an effective rep and a wasted one. They can show you modifications for different fitness levels and explain the biomechanics behind each movement.
This is the human touch that separates 12REPS from every other muscle building app on the market.
What the Muscle Highlight Feature Shows You
The muscle highlight technology in our 500+ tutorial videos is a game-changer for understanding exercise effectiveness. As the personal trainer performs the movement, you’ll see:
Real-Time Muscle Activation
Visual overlays highlight exactly which muscles are working during each phase of the exercise. This helps you:
- Understand the primary muscles being targeted
- Identify secondary and stabilising muscles
- Recognise when specific muscle groups should engage
- Verify you’re feeling the exercise in the right places
Phase-by-Phase Breakdown
The eccentric (lowering) and concentric (lifting) phases are clearly demonstrated with muscle highlights showing you:
- Which muscles contract during the lift
- Which muscles control the descent
- How to maintain tension throughout the full range of motion
- Where you should feel the stretch and squeeze
Mind-Muscle Connection
Understanding which muscles should be working transforms your training. When you can visualise the target muscles during your workout, you develop a stronger mind-muscle connection, leading to better activation, increased muscle growth, and more effective training sessions.
The Complete 12REPS Video Library
Compound Movements: Comprehensive tutorials for all major barbell and dumbbell lifts including squats, deadlifts, bench press, overhead press, rows, and pull-ups. These form the foundation of any effective strength training programme, and our detailed tutorials ensure you master proper technique.
Isolation Exercises: Professional demonstrations of targeted movements for specific muscle groups, from bicep curls and tricep extensions to calf raises and lateral raises. Perfect for addressing weaknesses or focussing on aesthetic development.
Bodyweight Training: Complete bodyweight progressions demonstrated by certified trainers, allowing you to build serious strength at home without any equipment. From beginner variations to advanced calisthenics movements.
Machine Exercises: Proper setup and execution for every common gym machine, ensuring you get maximum benefit from your commercial gym membership. Our trainers show you the correct seat height, grip width, and movement pattern for optimal results.
Functional Training: Kettlebell swings, Turkish get-ups, battle rope exercises, and other functional movements that improve athletic performance and real-world strength, all demonstrated with proper form and coaching cues.
HIIT and Conditioning: High-intensity exercises including burpees, mountain climbers, box jumps, and sprint variations for fat loss and cardiovascular conditioning, performed by trainers who understand how to maximise intensity safely.
Step-by-Step Tutorial Breakdown
The 500+ detailed tutorial videos follow a structured teaching format:
Introduction and Setup The personal trainer explains the exercise, its benefits, and the muscles it targets. You’ll learn proper equipment setup, starting position, and safety considerations before attempting the movement.
Movement Execution Watch as the trainer performs the exercise with muscle highlights showing exactly which areas are working. They explain:
- The starting position and grip
- How to initiate the movement
- The proper path of motion
- The end position and how to control the descent
- Breathing patterns throughout the exercise
Common Mistakes Real examples of incorrect form with explanations of why these mistakes happen and how they can lead to injury or reduced effectiveness. This preventative guidance is invaluable.
Coaching Cues Specific verbal cues that help you remember proper form during your workout. These are the same cues personal trainers use with in-person clients—simple phrases that immediately improve your technique.
Modifications and Progressions Learn how to scale the exercise up or down based on your current strength level. This makes 12REPS the best home and gym workout app for all experience levels.
Why This Makes 12REPS the Best Weightlifting App
When you combine professional exercise videos with the other features that make 12REPS exceptional, you get an unmatched training experience:
Expert Programming Meets Expert Instruction
The weekly workout programmes in 12REPS are designed by certified personal trainers. When you open your workout, you’re not just seeing a list of exercises—you’re getting a complete coaching experience. Each exercise links to professional demonstrations and detailed tutorials, ensuring you understand exactly how to execute the movement.
Learn While You Train
Other workout tracker apps just log your sets and reps. 12REPS educates you. By watching professional demonstrations and detailed tutorials with muscle highlights, you develop a deeper understanding of training principles. You’re not just following a programme—you’re learning how to train effectively for life.
Build Confidence in the Gym
Gym intimidation is real, especially for beginners. Walking into a weights room without knowing proper form is terrifying. With 12REPS, you can watch professional demonstrations and detailed step-by-step tutorials before attempting any new exercise. This preparation builds confidence and ensures your first attempt is safe and effective.
Prevent Injuries Before They Happen
Poor form is the leading cause of training injuries. By learning proper technique from certified personal trainers before you step under a barbell, you dramatically reduce your injury risk. The muscle highlight feature helps you understand exactly how the exercise should feel, allowing you to self-correct during your workout.
How 12REPS Compares to Other Fitness Apps
Hevy: Uses animation good quality exercise videos, but they’re generic demonstrations without the detailed tutorials, step-by-step breakdowns, or muscle highlight technology that 12REPS provides.
Strong: Relies primarily on basic animations that show the movement pattern but lack the nuance of proper coaching from certified personal trainers. No detailed tutorials or educational content.
JEFIT: Features generic exercise demonstrations without the comprehensive tutorial system or muscle highlight technology that helps you truly understand each movement.
12REPS: Over 2,000 professional videos including 1,500+ exercise demonstrations performed by certified personal trainers PLUS 500+ detailed tutorial videos with step-by-step instructions and muscle highlight overlays. You’re learning from qualified professionals who understand the science of training.
The Complete 12REPS Experience
Professional exercise videos are just one part of what makes 12REPS the best muscle and weight loss app:
Weekly Workout Programmes Designed by certified personal trainers, not generic algorithms.
Custom Routine Builder Build your own workout routine for the gym using any of the 1,500+ professionally demonstrated exercises.
Comprehensive Tracking Track your reps, sets, weight, 1RM, and total volume lifted. See your progress through clear graphs and statistics.
Home and Gym Flexibility Train anywhere with programmes that adapt to your available equipment.
Global Community Connect with lifters worldwide, share your progress, and find motivation from others on the same journey.
Expert Video Instruction Throughout From quick exercise demonstrations to detailed tutorials with muscle highlights, you’re guided by qualified personal trainers at every step.
Your Training Deserves Professional Instruction
You wouldn’t hire a personal trainer who couldn’t demonstrate proper form or explain which muscles you should be targeting. Why would you use a workout app that relies on generic videos or basic animations?
12REPS gives you access to over 2,000 professional exercise videos from certified personal trainers—including 500+ detailed tutorials with step-by-step instructions and muscle highlight technology. This is the same quality coaching that clients pay £70+ per hour to receive in person.
Every time you perform an exercise in 12REPS, you’re learning from qualified professionals who have dedicated years to mastering the science and practice of strength training. This expertise, combined with smart programming, comprehensive tracking, and a supportive community, creates the most effective training experience available
Learn proper form from certified personal trainers. Watch 500+ detailed tutorials with muscle highlights. Build muscle with expert programming. Track every aspect of your progress. Connect with lifters globally.
Download the best home and gym workout app with 2,000+ professional exercise videos from certified personal trainers.
Transform your training. Master proper form. See exactly which muscles are working. Achieve your goals with 12REPS.
