RRS Education Research Reviews DATABASE
Muscle Activation Levels & Traditional Latissimus Dorsi Weight Training
Research Review by Dr. Shawn Thistle©
Study Title:Variations in muscle activation levels during traditional latissimus dorsi weight training exercises: An experimental study.
Authors:Lehman GJ, Buchan DD, Lundy A, Myers N, Nalborczyk A
Publication Information:Dynamic Medicine 2004; 3:4 (BioMedCentral)
Summary:Personal trainers and physical/manual therapists often espouse that different grip variations can influence muscle activity during a number of resistance training exercises. One particular example of this is the latissimus pull-down exercise, where it is often said that bicep activity prevails during a supinated, close-grip technique while latissumus activity is maximized by the common overhand, wide-grip technique.
The aim of this study was to examine this theory, as well as the theory that actively retracting the scapulae during a seating row increases the activity of the middle trapezius and rhomboid musculature.
Twelve healthy, previously trained males (average age 27 years) free of back pain or upper extremity injury took part in this study. Surface electrodes were used to record activity of the biceps, latissimus dorsi, middle trapezius and rhomboid musculature during four exercise tasks:
- wide grip pull-down (overhand grip at 150% of biacromial distance [shoulder width])
- reverse grip pull-down (supinated grip at 100% BAD)
- seated row, shoulders retracted - forearms at mid-pronation, 6 inches apart, shoulders actively retracted during motion
- seated row, shoulders slack - same as #3, but shoulder girdle allowed to roll forward
This study produced some surprising results:
- latissimus dorsi activity was greater during the seated row with protracted (rounded) scapulae than either of the pull-down exercises
- the level of protraction/retraction did not effect latissimus activity during the seated rowing exercises
- forearm pronation/supination had no effect on latissimus activity during the pull-down
- biceps activity remained constant across all exercises
Conclusions & Practical Application:This study refutes the commonly held beliefs that a wide-grip pull-down preferentially activates the lats while a supinated-grip increases biceps activity during a pull-down. Further, it also refutes the idea that actively retracting the scapulae during a seated row increases the activity of the middle scapular stabilizers (middle trapezius and rhomboid).
Some shortcomings of this study should be noted however. First, only one part of the lats were used for EMG recording, meaning other parts of the muscle that weren't investigated may have experienced a change in EMG activity. Further, the weights used may not have been enough to fully elucidate the effects of these grip/technique modifications. However, the weights used in the study (10-12 rep maximum) do represent intensities commonly employed by personal trainers with average clients.
The exercise and fitness industry is laden with myths and falsehoods and this study provides early evidence that helps clarify the effects of varying grip and technique for pulling exercises.
Pulling exercises are a cornerstone of most training exercises and my intent here is not to debate their utility. Our goal as professionals however, should be to continue the quest for knowledge regarding the actual effects of these modifications.