Biomechanics of the Lat Pulldown

The lat pulldown is one of the most popular exercises used to strengthen the muscles of the back. The purpose of this article is to provide an overview of the lat pulldown exercise including movement requirements, joint actions, and involved musculature. In addition, this article provides findings from relevant research discussing various grip positions of the lat pulldown exercise.

Learning Objectives:

  1. Understand the movement requirements, joint actions, and involved musculature of the lat pulldown exercise.
  2. Differentiate various grip positions of the lat pulldown.
  3. Provide exercise technique recommendations for fitness enthusiasts wishing to perform the lat pulldown exercise.

Introduction

The lat pulldown (short for latissimus dorsi pulldown) is one of the most popular exercises used to strengthen the muscles of the back. While there are fewer studies investigating the lat pulldown compared to more popular exercises such as the squat or bench press, there is ample evidence describing its effectiveness for targeting many muscles of the back and arms (Lusk et al., 2010; Synder & Leech, 2009; Sperandei et al., 2009; Signorile, Zink, & Szwed, 2002). There are some variations of the lat pulldown exercise including the close-grip pulldown, wide-grip pulldown, reverse-grip (supination) pulldown, and neutral-grip pulldown (to name a few).

Overview

The lat pulldown is a compound exercise designed to target many muscles of the back, most notably the latissimus dorsi (Figure 1). The primary joint actions that occur during the lat pulldown are listed below however, it is important to note that accessory joint motions occur depending on how the individual performs the exercise.

Figure 1Figure 1. Lat Pulldown

Concentric Phase (pulling bar towards the chest)

  • Shoulder adduction
  • Shoulder horizontal abduction
  • Elbow flexion
  • Scapulae downward rotation
  • Scapulae retraction

Eccentric Phase (returning to the start position)

  • Shoulder abduction
  • Shoulder horizontal adduction
  • Elbow extension
  • Scapulae upward rotation
  • Scapulae protraction

Table 1 provides a list of involved musculature. This is not a complete list as many muscles are involved in the joint actions listed above. It is also important to note that muscle activation varies depending if the muscle is performing an eccentric muscle action or a concentric muscle contraction, as well as the technique selected by the exerciser.

Table 1. Lat Pulldown: Targeted Muscle Groups
Agonists
  • Latissimus Dorsi (largest back muscle)
  • Teres Major (muscle near the bottom portion of the shoulder blade)
Synergists
  • Posterior Deltoid (back of the shoulder muscle)
  • Trapezius- upper, middle, lower) (a large trapezoid shaped muscle of the back)
  • Rhomboids (muscle that connects to the shoulder blades and spine)
  • Levator Scapulae (located near the side and back of the neck)
  • Biceps Brachii (front of upper arm muscle)
  • Brachialis /Brachioradialis (forearm muscles)
Stabilizers
  • Triceps brachii (back of upper arm muscle)
  • Rotator cuff (small muscles situated around the shoulder blades)
Eccentric Muscle Action: When a muscle exerts force while lengthening, usually because it is returning from a shortened (concentric) position to its natural resting position. Also known as a lengthening contraction and as the “negative” during resistance training exercises.

Concentric Muscle Contraction:When a muscle exerts force while shortening.

Technique

Starting Position

  • Adjust the lat pulldown machine to fit your body.
    • Adjust the pads so your knees are placed securely underneath. For ideal posture, the hips and knees should be roughly at 90° angles with the feet flat and securely on the floor about hip-width apart.
  • Grasp the bar with your hands shoulder-width or slightly wider than shoulder-width apart.
  • Abdomen should be drawn-in and braced.
    • Drawing-in and abdominal bracing activates the inner unit (transverse abdominis, multifidus, pelvic floor- muscles close to the spine) and global abdominal muscles (rectus abdominis, external obliques – superficial abdominal muscles) offering greater spinal stability.
  • Slightly lean the torso back about 20-30° to optimally match the line of pull of the latissimus dorsi with the cable machine.
    • Keep the spine in a neutral position and avoid excessive lumbar extension (arching the low-back).

Movement Pattern

  • Pull the bar toward your chest, by flexing your elbows while simultaneously performing shoulder adduction and scapulae retraction/depression (squeeze your shoulder blades together). Lower the bar until a slight stretch is felt in the pectorals and a full contraction of the latissimus dorsi and scapulae retractors occurs. This typically occurs when the bar is just above or touching the upper chest. However, a person’s shoulder mobility may prevent a full range of motion and in this case using the 90° rule (upper arms parallel to the floor, 90° of elbow flexion) may be a safer alternative.
    • Avoid letting the low-back arch, the head to jut forward, or the shoulders to shrug during this motion in order to maintain an ideal and safe posture.
    • Preserve a natural lordosis curvature of the lumbar spine throughout the entire lift.
    • Keep the trunk stabilized and avoid swinging the torso throughout the movement. While swinging the torso creates momentum and the ability to use heavier loads, it places less emphasis on the latissimus dorsi and scapulae retractors and more activation of the lumbar erector spinae muscle groups (muscles of the low-back).
  • Slowly return to the starting position by extending the elbows and abducting the shoulders. The motion also includes upward rotation and slight protraction of the scapulae.
    • During this phase, a common mistake is to allow the bar to rise too quickly. Maintain full control of the weight to enable an ideal eccentric muscle contraction.

Breathing Pattern

  • Exhale during the concentric phase of the exercise.
  • Inhale during the eccentric phase of the exercise.

Behind-the-Neck Lat Pulldown

Performing behind-the-neck lat pulldowns is a controversial exercise and one that should be avoided. While behind-the-neck pulldowns can effectively target the latissimus dorsi, the pros do not outweigh the cons. The same or greater levels of muscle activation occurs with front-of-the-neck lat pulldowns, in addition to the body maintaining better posture and joint alignment.

Behind-the-neck-pulldowns require the individual to jut their head forward to provide a clear path for the bar towards the base of the neck. A forward head posture can promote muscular tightness of several large neck muscles (i.e., sternocleidomastoid, levator scapulae, scalenes). A forward head posture has also been implicated in neck injury and even headaches (Yip, Chiu, & Poon, 2008; Fernández-de-Las-Peñas et al., 2007). As such, individuals should aim to perform resistance training exercises with a neutral cervical spine posture.

In addition, a behind-the-neck lat pulldown may cause greater stress to the shoulder capsule and ligaments. Some speculate this exercise may even cause greater risk to the rotator cuff musculature. This may be due to excessive external rotation of the shoulder when performing this exercise, however more research is needed to support or refute this claim.

Grip Positions

There are variations in grip positions a person can use when performing the lat pulldown exercise. Grip positions include a pronated narrow-grip (hands closer than shoulder-width), pronated wide-grip (hands greater than shoulder-width), a narrow neutral-grip, a wide neutral-grip, and a supinated-grip (Figure 2).

Figure 2. Grip Positions
Pronated narrow-grip Pronated narrow-grip
Pronated wide-grip Pronated wide-grip
Narrow neutral grip Narrow neutral grip
Wide neutral grip Wide neutral grip
Supinated grip Supinated grip

Research Concerning Grip Position

There is confusion within the fitness industry if a wide-grip lat pulldown activates the latissimus dorsi and other muscles more so than a narrow-grip. As such, Andersen et al., (2014) performed a research study to examine this very question. Fifteen men participated in the study. The researchers compared three different pronated grip widths: close, medium and wide-grips (1, 1.5, and 2 times biacromial distance) using electromyographic (EMG) activity. They found similar activation of the latissumis dorsi between all three grips during the concentric phase of the exercise. However, the biceps brachii tended to have higher activation levels using a narrow or medium-grip versus a wide-grip. Lastly, the wide and medium-grips displayed greater activation of the latissimus dorsi than the narrow-grip during the eccentric phase of the exercise. As such, the researchers suggest a medium pronated-grip may be a slightly better option, but fitness enthusiasts and athletes alike should expect similar results in strength and muscle size no matter which grip they choose.

Biacromial distance: The length measured from the end of one shoulder to the end of the opposite shoulder.
Electromyography (EMG): A diagnostic technique used for assessing and recording the electrical activity produced by muscles.

A 2009 study by Lusk et al., also examined various grip positions of the lat pulldown exercise. The researchers compared activation of the latissimus dorsi, middle trapezius, and biceps brachii muscle groups using four different grips; wide-pronated, wide-supinated, narrow-pronated, and narrow-supinated. Twelve men participated in the study. Their findings suggested a pronated-grip (both wide and narrow) activates the latissimus dorsi more so than a supinated-grip. They did not record any major differences in biceps brachii or middle trapezius activation amongst the varying grips. The researchers concluded a pronated-grip (either wide or narrow) is best for activating the latissimus dorsi.

Lastly, a 2002 study by Signorile, Zink, and Szwed (2002), investigated the effects of different grip positions (close neutral-grip, close supinated-grip, wide-grip front of neck, and wide-grip behind the neck) on EMG activity of shoulder muscles during the lat pull-down exercise. They specifically measured EMG activity of the latissimus dorsi, pectoralis major, teres major, and long head of the triceps brachii. The authors found numerous differences between all of the grip positions. However the wide-grip performed to the front of the neck produced the greatest latissimus dorsi activation. The authors suggest using a variety of grip positions that are specific to a person’s needs and goals.

Examining the different research findings, it may be slightly advantageous to use a medium or wide pronated grip to activate and strengthen the latissimus dorsi. Yet, one should not expect to see noticeable changes in strength or muscle size by specifically choosing one grip over another. To minimize boredom and maximize exercise adherence it may be best to perform a variety of grip positions during the lat pulldown exercise (except behind-the-neck pulldowns).

Lat Pulldown vs. Pull-up

The pull-up and lat pulldown exercises both target the muscles of the back. However, there is one major distinction. The lat pulldown is an open-chained exercise whereas the pull-up is a closed-chain exercise. Research demonstrates that closed-chain exercises may result in greater motor unit recruitment (more muscle fibers activated) when compared with open-chain exercises (Augustsson et al., 1998; Brindle et al., 2002; Ucar et al., 2014). In addition, a study by Doma, Deakin, and Ness (2013) concluded the chin-up is a more “functional” exercise when compared to the lat pulldown.

Closed-chain exercises are physical movements in which the hands or feet are in a fixed position with an immobile surface (such as the ground or fixed anchor point) and cannot move. When force is applied by the individual, their force is not great enough to overcome the immobile surface, and as a result the rest of the body moves in accordance. For example, during the concentric phase of a pull-up, the exerciser applies a pulling force to the bar, and as a result the elbows flex versus the bar breaking away from its support.

Open-chain exercises are physical movements in which in which the hands or feet are not in a fixed position with an immobile object, and as a result the force applied by the person is great enough to overcome the resistance. This type of resistance usually comes in the form of external load such as barbells, dumbbells, or selectorized strength-training machines. For example, during a lat pulldown an exerciser applies a pulling force to the bar, and subsequently the bar is pulled towards his or her chest.

Given the benefits of closed-chain exercises, one might be inclined to make a general statement that open-chained exercises are not functional and should be avoided during an exercise routine. However, as already discussed the lat pulldown is an effective exercise for strengthening many muscles of the back. It can and should be supplemented with other closed-chain strength training exercises such as the pull-up or chin-up.

Recommendations

For those new to exercise it is important to take a progressive and systematic approach to the lat pulldown. Start with a relatively light weight and focus on optimizing technique. The primary focus should be on learning how to properly retract the shoulder blades without movement compensations (i.e., jutting the head forward, shrugging the shoulders). Proper technique should be the emphasis before adding additional load or focusing on maximal lifts. Start with a standard pronated grip of the bar approximately shoulder-width. As confidence grows, fitness enthusiasts can begin to explore a variety of grip positions. Keep the volume relatively low to avoid overtraining and unnecessary muscle soreness. However, anyone who experiences shoulder pain should seek medical clearance before returning to their exercise program. Lastly, include additional resistance training exercises for the back to improve overall strength and muscle symmetry. These exercises can be a variety of open-and-closed-chain exercises.

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