The pectoral muscle group is a set of muscles notoriously difficult to train in an isolationary capacity, as their primary mechanism of action is the movement and stabilization of the arms - though several exercises such as the pec deck come quite close to achieving this goal.
The pec deck is a chest muscle isolation exercise performed with the usage of a machine that provides opposing resistance to the forearms and elbows so as to induce sufficient hypertrophic stimulus in the pectoralis minor and major.
However, the pec deck may require substitution with a suitable alternative exercise, as it presents its own set of risks and drawbacks such as poor synergist muscle activation and risk of elbow impingement - all of which may easily be avoided through the usage of an exercise with different mechanics but a similar training stimulus.
As was previously mentioned, though the pec deck is a highly effective exercise that is perfectly suitable for most healthy exercisers; certain issues with its training stimulus or angle of resistance can cause individuals to seek out an exercise that achieves the same end result, though with a different set of disadvantages.
The most common of these disadvantages is the simple fact that the pec deck does not properly train the isometric strength of the pectoral muscle group and nearby skeletal muscle structures, resulting in poor carry-over to free weight compound exercises, athletic sports related activities or simple everyday tasks.
Other frequently seen issues with the pec deck that can call for its substitution are to do with its angle of resistance, wherein the exerciser may experience shoulder, elbow or clavicular pain as they shift these tissues out of their structurally sound positioning, causing instability and potential injury if excessive resistance or poor form is also a factor.
Finally, there is also the case of exercisers being unable to access a pec deck machine, requiring that the exercise be substituted with one of similar muscle group activation and intensity so as to retain the original purpose of the pec deck within the exerciser’s training routine.
A suitable alternative to the pec deck must possess a similar muscle group activation set - that is to say, that it also trains the pectoralis minor and major muscles that make up the chest. Whether or not this alternative exercise also includes other muscle groups as a compound movement will depend on the exerciser’s goals and the structuring of their training program.
Moreover, the alternative exercise must also induce a level of intensity in accordance with the exerciser’s needs, with lesser exercise intensity for injured individuals or novice exercisers who find the pec deck to be too strenuous, and greater intensity for athletes who find the relative activation of the pec deck to be insufficient for their progressive development.
Finally, there is a matter of the alternative exercise’s mechanics in comparison to the pec deck, with certain alternatives such as the cable chest fly or slider push up recreating the movement of the pec deck, though with a more forgiving and stable angle of resistance.
The sort of mechanics and form cues used by the alternative exercise should be in accordance to the physiology and needs of the exerciser, as a history of elbow injuries or pec tears - for example - will obviously make certain movements like dumbbell flys potentially dangerous if performed by the exerciser.
The sole muscle group trained by the pec deck (and any potential alternative exercise therein) is that of the pectoral muscles, and as such a large number of exercises may act as suitable substitutes to the pec deck so long as they also meet the other training needs of the exerciser.
It should be noted that, in ordinary training programs, the pec deck is often programmed as an accessory isolation exercise meant to maximize muscular hypertrophy and strength development - and as such, substituting the pec deck with a chest-based compound movement like the bench press or chest press can lead to injury and overtraining unless further restructuring of the workout program is done.
While this is not to say that the pec deck cannot be alternated out with a compound exercise, it is still best to only do so if the exerciser is knowledgeable enough of their own physical limits and on workout programming to make such a change in a safe manner.
The cable crossover is among one one of the best possible alternatives to the pec deck, as it not only recreates the angle of resistance, muscle group activation and mechanics of the exercise in a safer manner - but also is capable of activating the pectoral muscles in a greater capacity than the pec deck itself.
This is due to the fact that the cable crossover crosses the exerciser’s wrist over the other, further activating the pectoralis minor muscle than what the pec deck’s limited range of motion will allow.
In addition to this, the cable crossover’s more variable angle of resistance and variable pulley elevation allows the exerciser to better tailor the machine to their own proportions and mobility, reducing the risk of injury and allowing them to take full advantage of their own individual biomechanics.
When substituting the pec deck with the cable crossover, the exerciser may simply copy the same programming of the pec deck; matching the volume and level of resistance to the cable crossover, with no further restructuring or alteration in set and repetition schemes needing to be made.
If the exerciser wishes to retain the pec deck’s machine-based training stimulus in the alternative exercise, simply utilizing a similar machine-based chest exercise should prove more than sufficient - providing much the same benefits as any other exercise performed with the use of an exercise machine, such as greater stability and reduced risk of injury.
Quite similar to a cable crossover save for a reduced range of motion that better recreates that of the pec deck, cable chest flys also act as an isolation exercise that solely trains the pectoralis muscle group - with the added benefit of a more free range of motion and angle of resistance, reducing strain on the elbows and shoulders as the exerciser can better tailor the movement to their own biomechanics.
Just as in the case of the cable crossover, substituting the pec deck with the cable chest flys requires no further alteration of the workout program, allowing the exerciser to simply substitute the pec deck in a one to one ratio in terms of volume and resistance.
One of the more uncommon pectoralis muscle group isolation exercises, the lying cable fly is simply a cable fly performed with the exerciser in a supine position atop a bench or similar surface.
This variation of the cable fly greatly reduces stress placed on the shoulder and elbow while intensifying pectoralis major muscle activation due to the altered angle of resistance and greater torso stability involved.
The lying cable fly will usually require a lower level of resistance than the pec deck or standing cable fly, as the exerciser will be unable to press as far forward with their upper torso, reducing their total strength output and placing them in a disadvantageous position despite the increased pectoral muscle group recruitment.
As such, while the exerciser may substitute the pec deck with the lying cable fly in a one to one ratio in terms of volume, the total resistance between the two exercises will be distinctly different despite a similar level of intensity involved.
For cases wherein the exerciser does not have access to any sort of fitness equipment except free weights - or otherwise does not wish to make use of machine-based exercises, the usage of free weight-based pectoral muscle group exercises should prove more than sufficient for providing isolation-type training stimulus to the chest muscles.
A classic among chest building exercises, dumbbell flys are the free weight counterpart to the pec deck, providing highly targeted pectoralis major and pectoralis minor activation in an isolationary capacity.
Unlike the pec deck however, dumbbell flys are performed while the exerciser is lying upon their back, forming the body in such a way that the angle of resistance is less injurious and as such results in less elbow and shoulder pain - so long as the scapula remains in a stable and advantageous position.
As an added benefit, the free weight nature of the dumbbell fly provides not only dynamic but also isometric contraction of the pectoralis muscle group, directly translating into greater athletic capacity in terms of activities involving the chest muscles.
However, switching to the dumbbell fly from the pec deck will require some alteration in the structure of the workout session and the programming of the exercise itself, as the greater exertion and the fact that the dumbbell fly also activates the biceps brachii and posterior deltoid head can lead to injury and overtraining if not accounted for.
This is in combination with the greater intensity of the dumbbell fly exercise, of which will dictate that a lesser volume of repetitions be used alongside a lower amount of relative weight in comparison to the pec deck.
Another highly effective exercise that targets the pectoral muscles in a similar intensity to the pec deck, the dumbbell chest pullover is performed with the exerciser lying atop a bench and lowering a dumbbell behind their head with both hands, thereby stretching the chest muscles while also co-activating the triceps, latissimus dorsi and teres major - thereby placing the dumbbell chest pullover in the compound exercise category.
As was previously mentioned in this article, as the pec deck is an isolation exercise, substituting it with a compound movement such as the dumbbell chest pullover will require some restructuring of the workout program, namely; reducing the total volume placed on these activated muscle groups.
The dumbbell chest pullover may therein act as a pec deck substitute only if all other possible alternative exercises have already been attempted, as though it is indeed a suitable alternative exercise as well - it is the least similar among all other exercises mentioned in this article.
When programming the dumbbell chest pullover as a pec deck alternative, the exerciser will need to reduce both the total amount of weight used during the exercise as well as the total volume per set. This is not only because of its greater number of muscle groups activated, but also because of the fact that it places strain on certain parts of the body that are otherwise at risk of being injured.
Though sliders are more often reserved for home gym workouts and are otherwise rather situational in their usage, the slider fly exercise is one particular alternative to the pec deck that is not only convenient but also considerably safer in regards to the exerciser’s elbows and shoulders.
This exercise is performed by the exerciser assuming a standard push up position before allowing their arms to slide outward in opposite directions prior to reversing the motion, with the sliders serving to reduce friction between their hands and the floor.
Not only does this greatly activate the pectoralis muscle group in a manner quite similar to the pec deck, but may also be tailored to an exerciser’s unique physiology and training experience - making it suitable for physical rehabilitation patients, athletes who find the pec deck to be ineffective or regular exercisers seeking a change in their training program.
As the slider push up fly’s total resistance is relative to the exerciser’s own bodyweight, the length of their arms as well as several other factors such as the material the floor is made of - programming it in equivalency to the pec deck will vary on a case by case basis, though most individuals will find that performing the slider push up fly with a greater amount of volume is far more preferable.
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