Pull-ups: Why You're Strong But Still Can't Do Them

Why can I lift a lot but not do pull-ups?

It's a common paradox: you might be able to deadlift twice your body weight or bench press significant loads, yet struggle to perform a single unassisted pull-up. This discrepancy arises primarily from the unique demands of the pull-up, which tests relative strength, specific muscle group activation, grip endurance, and neuromuscular coordination in ways that many traditional lifting exercises do not.

Relative Strength vs. Absolute Strength

One of the most significant factors is the distinction between absolute strength and relative strength. Absolute strength refers to the maximum amount of force you can exert, regardless of your body weight. This is what's typically measured in lifts like the deadlift or squat, where you're moving an external load. Relative strength, however, is your strength in proportion to your own body weight. A pull-up requires you to lift and control your entire body mass against gravity. If you weigh 200 pounds, a pull-up is a 200-pound vertical pull, whereas a 200-pound bench press is an absolute strength measure where your body weight isn't directly part of the load. Individuals with a higher body fat percentage relative to lean muscle mass will find pull-ups disproportionately challenging due to the increased load they must move.

Specificity of Training

The Principle of Specificity (SAID: Specific Adaptation to Imposed Demands) dictates that your body adapts specifically to the type of training it undergoes. If your training primarily involves horizontal pushing (e.g., bench press), lower body pushing (e.g., squats), or hip-hinging (e.g., deadlifts), you'll develop strength in those specific movement patterns and muscle groups. Pull-ups are a vertical pulling movement, recruiting a distinct set of muscles in a specific coordination pattern. Training exclusively with barbells and dumbbells for other movements will build general strength, but not necessarily the highly specific strength and motor patterns required for a pull-up.

Distinct Muscle Recruitment Patterns

The primary movers for a pull-up differ significantly from those used in many common gym lifts:

• Pull-up Primary Movers:
  • Latissimus Dorsi (Lats): The large back muscles responsible for shoulder adduction, extension, and internal rotation. They are the powerhouse of the pull-up.
  • Biceps Brachii: Essential for elbow flexion.
  • Rhomboids and Trapezius: Contribute to scapular retraction and depression, stabilizing the shoulder blades.
  • Posterior Deltoids: Assist the lats in shoulder extension.
  • Forearm Flexors: Crucial for grip.
• Common Lifting Primary Movers (Examples):
  • Bench Press: Pectoralis major, anterior deltoids, triceps brachii (horizontal pushing).
  • Squat: Quadriceps, gluteus maximus, hamstrings (lower body pushing).
  • Deadlift: Gluteus maximus, hamstrings, erector spinae, quadriceps, trapezius (posterior chain dominant, hip hinge).

While some muscles, like the trapezius, might be involved in both, their primary roles and the overall movement mechanics are vastly different. Your body prioritizes strength development in the specific movement patterns you train.

The Critical Role of Grip Strength

A often-overlooked limiting factor in pull-ups is grip strength and endurance. Unlike a deadlift where you might use a mixed grip or straps to manage the load, a pull-up requires a sustained, strong overhand grip to support your entire body weight. If your forearm flexors fatigue before your lats or biceps, you simply won't be able to hold onto the bar, regardless of your upper body pulling strength. Many heavy lifters have strong grips for static holds, but the dynamic, sustained nature of the pull-up can expose weaknesses in grip endurance.

Core Stability and Kinesthetic Awareness

A successful pull-up isn't just about arm and back strength; it demands significant core stability. Your abdominal muscles, obliques, and erector spinae work synergistically to prevent your body from swinging and to maintain a rigid, efficient pulling posture. A weak core can lead to inefficient movement, energy leaks, and an inability to transfer force effectively from your lower body to your upper body during the pull. Furthermore, kinesthetic awareness (your body's ability to sense its position and movement) and coordination are vital for the smooth, controlled execution of a pull-up, which is a more complex motor skill than many isolated strength exercises.

Body Composition Considerations

As mentioned under relative strength, body composition plays a significant role. If you carry a higher percentage of body fat, the "load" you are pulling (your body weight) is greater, but the amount of force-producing muscle mass might not be proportionally higher. This makes the strength-to-weight ratio less favorable for pull-ups. Conversely, a leaner individual with a high lean muscle mass will have a distinct advantage.

Addressing the Imbalance: How to Improve Your Pull-ups

If you're strong but struggle with pull-ups, targeted training can bridge the gap:

• Negative Pull-ups: Start at the top of the pull-up (chin over the bar) and slowly lower yourself down, controlling the descent for 3-5 seconds. This builds eccentric strength, which is crucial for the movement.
• Assisted Pull-ups: Use a resistance band looped around the bar and your feet/knees, a pull-up assist machine, or a spotter to reduce the load. Gradually decrease assistance as you get stronger.
• Lat Pulldowns: While not identical, lat pulldowns mimic the vertical pulling motion and strengthen the primary muscles (lats, biceps) involved in pull-ups. Focus on proper form and engaging your lats.
• Inverted Rows (Bodyweight Rows): These horizontal pulling exercises build back strength and scapular control, with the intensity easily adjusted by changing your body angle.
• Grip Strength Training: Incorporate dead hangs, farmer's carries, and plate pinches to improve your forearm and grip endurance.
• Core Strengthening: Integrate exercises like planks, hollow holds, and leg raises to build the necessary trunk stability.
• Consistency and Progression: Like any skill, pull-ups require consistent practice and progressive overload. Gradually challenge yourself with more repetitions, sets, or less assistance over time.

Conclusion: Embrace the Challenge

The journey from being strong in general lifts to mastering the pull-up is a testament to the specificity of human movement and adaptation. It's a common, surmountable challenge that highlights the importance of training diverse movement patterns and addressing specific muscular and neurological demands. By understanding the underlying reasons for this discrepancy and implementing targeted training strategies, you can bridge the gap and add the impressive and highly functional pull-up to your strength repertoire.