Overcoming Isometrics for Strength, Size, & Performance
Dr. Joel Seedman, Ph.D.
Research studies have shown that post activation potentiation (PAP) is one of the most effective mechanisms we know of for maximizing power output, high threshold motor unit recruitment, explosive power, and speed, both during training and competition. Post activation potentiation (PAP) is a physiological phenomenon in which an intense series of voluntary muscular contractions, typically performed using heavy isotonic movements (i.e. barbell back squat) produces temporary increases in peak force and power during subsequent explosive activities. Read more about post activation potentiation in 3 part article literature review here.
For instance, performing a set of heavy back squats several minutes prior to an explosive activity, such as jumping or sprinting, can produce a boost in power and speed during those activities resulting in higher jumps and better sprint times. Similar effects have also been demonstrated in the context of upper body activities.
Here are several examples of post activation potentiation circuits consisting of a heavy compound lift performed several minutes prior to an explosive jumping exercise as demonstrated by a few of my pro athletes. Read more about my 40 top jumping exercises here.
While the exact physiological processes that may contribute to this response are still a matter of debate it appears that increased higher threshold motor unit recruitment may be the strongest contributor as heavy loading may help wake up these motor units. Once activated, they may be more easily recruited during explosive activities.
Regardless of the exact mechanisms involved, it’s quite clear that achieving PAP can create a temporary increase in power-related performance that can potentially translate to long-term improvements in performance, speed, and power.
Overcoming Isometrics vs Traditional Isotonic Repetitions
Although a majority of the aforementioned studies implemented isotonic exercises via the use of traditional free weight movements such as barbell squats and bench press, various studies have explored the use of overcoming isometric exercises, i.e. pressing/pulling against an immovable object, as a means of producing a post activation potentiation effect in both the upper and lower body.
Most of these investigations concluded that overcoming isometrics are superior to traditional isotonic free weight exercises for producing PAP.
The exact mechanisms through which overcoming isometrics produce superior PAP results are not yet fully understood. The current hypothesis is that overcoming isometrics, by virtue of being a maximal voluntary contraction that typically lasts several seconds allows temporal summation or gradual ramping up of firing frequency and motor unit recruitment to occur over time. Simply put, with each passing second the level of motor activation continues to ramp until it approaches or hits near maximal activation and recruitment levels.
Another way to think about it is that, typically, it takes several seconds of intense activation for an individual to achieve maximal motor unit recruitment. Unfortunately, most traditional repetitions end before maximal activation occurs. The overcoming isometric allows the nervous system to progressively ramp up with each passing second until maximal recruitment is achieved. In other words, you may achieve 50% maximal recruitment in the first second and 75% in the next second. By the third second you may finally reach close to 100% activation as you press with maximal intensity against the immovable object. At this point you’ll experience heightened levels of motor unit recruitment and intramuscular tension that are almost impossible to replicate with any other training method.
Additionally, it has been suggested that overcoming isometrics may permanently improve a lifters ability to recruit high threshold motor units during normal training conditions as well as during athletic competition. Furthermore, it’s thought that the high levels of intramuscular tension produced from overcoming isometrics act as a strong stimulus for inducing muscular hypertrophy and size gains. With that said, overcoming isometrics can be used can be used on a variety of movements including bench press, squats, deadlifts, lunges, rows, bicep curls, and other exercises as a means of eliminating sticking points, increasing neuromuscular efficiency, and triggering functional strength and hypertrophy gains in targeted muscles.
Potential Issues with Overcoming Isometrics
Although overcoming isometrics appear to be superior to traditional isotonic free weight movements in terms of producing PAP, overcoming isometrics aren’t without their fair share of limitations and potential issues. For instance, without an eccentric pre-stretch or lengthening phase prior to initiating the overcoming contraction during which the muscles are attempting to shorten, the lifter misses out on the all important eccentric elements of movement. These include the proprioceptive feedback associated with eccentric contractions, the high threshold motor unit recruitment associated with alpha gamma co-activation, the contribution of the stretch reflex, and the decreased onset of fatigue associated with pre-stretching a muscle prior to concentric contractions.
So yes, in one sense overcoming isometrics may provide a greater potentiation response than traditional heavy isotonic repetitions (which is not surprising given the haphazard way in which most individuals approach the performance of traditional exercises), however, in and of themselves, they’re still far from optimal when it comes to maximizing the physiological effectiveness of each and every rep.
THE BEST OF BOTH WORLDS: COMBINING ECCENTRIC ISOMETRICS & OVERCOMING ISOMETRICS
The obvious solution is to combine overcoming isometrics with eccentric isometrics which I refer to as overcoming eccentric isometrics and which may in fact provide the best of all worlds as they not only have the potential to produce just as much if not more potentiation and neural drive than traditional overcoming isometrics, they also eliminate the disadvantages associated with movements that lack the eccentric elements mentioned above. Read more about eccentric isometrics in my book MOVEMENT REDEFINED.
I should also note that in my research studies at the University of Georgia, eccentric isometrics produced a greater post activation potentiation response than traditional repetitions, similar to that seen when comparing overcoming isometrics to traditional repetitions. Unfortunately, as of yet there are no published studies comparing the effect of overcoming eccentric isometrics vs. overcoming isometrics alone on PAP. However, based on principles of neuromuscular and structural physiology one might reasonably predict that combining overcoming and eccentric isometrics would produce the strongest response as well as a host of other possible benefits.
Practical Application of Overcoming Eccentric Isometrics
For all the reasons previously alluded to, when implementing overcoming isometrics with my athletes I focus exclusively on overcoming eccentric isometrics, i.e. the combination of overcoming and eccentric isometrics, using relatively moderate loads (30-70% 1RM). Read more about eccentric isometrics in my book MOVEMENT REDEFINED.
In other words, they must pause in the stretched position using an eccentric isometric with moderate weight before driving into the pins. This helps to ensure there is some of degree of eccentric loading, pre stretch, pre-loading, and muscle spindle activation as described above which would not normally occur if one were to use an empty bar or simply press against an immovable stationary load (i.e. trying to press against a wall or a supramaximal load that is set on top of pins that can’t be moved).
The brief eccentric isometric in the bottom position helps to wake up muscle spindles, which enhances sensory feedback and improves body mechanics throughout the set. As noted earlier, most overcoming isometrics don't involve eccentric loading or pre-stretching of the muscles, therefore, the degree of somatosensory feedback produced by proprioceptive mechanisms such as muscle spindles is minimal to non-existent. As a corollary, because kinesthetic awareness and proprioceptive feedback during the set will be minimal at best, technique can easily begin to degrade.
Besides improving body awareness and somatosensory feedback, pre-stretching a muscle before intense concentric contractions has been shown to decrease the onset of fatigue. As a result the lifter is able to maintain higher quality of movement and higher force production on subsequent reps without form breaking down or excessive fatigue accumulation being the limiting factor. This is of even greater importance since studies suggest that the main limiting factor in terms of producing a strong PAP response is learning how to find the optimal balance between potentiation and fatigue.
Overcoming Eccentric Isometric Variations
There are an endless number of ways to use overcoming eccentric isometrics given that the protocol can be applied to almost any barbell or trap bar exercise. Shown here are some of my favorites.
Traditional Barbell Exercises
Barbell Overcoming Isometric Squats (Eccentric Isometric Version), Full squat article here.
Overcoming Eccentric Isometric Barbell Lunge
Overcoming Isometrics Incline Barbell Chest Press
Overcoming Isometrics Barbell Military Shoulder Press
Overcoming Eccentric Isometrics Bent Over Barbell Row
Overcoming Eccentric Isometric Squat Stance Deadlifts. Full Squat Stance Article Here.
Trap Bar Variations
Overcoming Eccentric Isometric Trap Bar Deadlift
Overcoming Eccentric Isometric Trap Bar Split Squat Lunge
Overcoming Isometric Trap Bar Row
Single Leg Variations
Overcoming Eccentric Isometric Single Leg Barbell Squats
Overcoming Eccentric Isometric Zercher Kickstand Squats
Overcoming Isometric Lunges and Single Leg RDL
Overcoming Isometric Single Leg Trap Bar Deadlifts
Single Arm Variations
Single Arm Barbell Suitcase Row
Overcoming Eccentric Isometrics Renegade Barbell Row. 50 More renegade rows here.
Bodyweight Exercises
Overcoming Eccentric Isometrics Pushups
Overcoming Eccentric Isometrics Pullups with Knee Flexion
Overcoming Eccentric Isometrics with Hip Flexion Knee Raise. Read more about proper pullup form.
Full Body Overcoming Eccentric Isometrics
Overcoming Eccentric Isometrics Squat and Curl
Overcoming Eccentric Isometrics Split Squat Lunging Overhead Press
Non-Squat Rack Options with Hanging Trap Bar Against Bench Protocol
Overcoming Eccentric Isometrics Hanging Trap Bar V-Grip Deadlift. Read about hanging trap bar.
Overcoming Isometrics Hanging Trap Bar V-Grip Row
Overcoming Eccentric Hanging Isometrics Trap Bar Split Squat Hack Lunge
Overcoming Eccentric Isometrics Trap Bar Chest Press
Overcoming Eccentric Isometrics Trapped Inside The Bar Chest Press
Overcoming Isometrics Hanging Trap Bar Row
Overcoming Isometrics Hanging Trap Bar RDL or Conventional Deadlift
Instantaneous PAP Protocol
Here is NFL athletes & GSP pro Austin Larkin performing a unique protocol that induces a more immediate post activation potentiation (PAP) effect that doesn’t require a rest period before going into the explosive movement.
5 key Points.
1. The protocol involves performing a loaded overcoming isometric against pins for 3-5 sec followed by an eccentric isometric to recharge the nervous system & create additional activation via alpha gamma co-contraction, followed by an explosive jump, then repeating.
2. Most research has examined the effects of performing overcoming isometrics (without the eccentric) followed by a several minute rest before the explosive event to allow fatigue to dissipate. However, I’ve found that while the more long-term post activation potentiation response (3-10 min after) requires significant fatigue dissipation, there’s also a more immediate PAP potentiation response where the neuromuscular system is so hyper-activated from the high levels of motor unit recruitment, that the neural ramping achieved from this lingers for several seconds in which case the athlete can rely on this short term neuromuscular memory to create an almost instantaneous post activation potentiation response. Think of this like swinging a weighted baseball bat followed several seconds later with a lighter bat.
3. Although you might assume the eccentric isometric induces greater fatigue is actually helps prevent fatigue while also creating additional activation & PAP More at link in bio.
4. This protocol helps reinforce co-contraction on the eccentric isometrics as anything but this & attempting to resist the eccentric lengthening will produce fatigue within seconds. Co-contraction helps dissipate fatigue.
Landmine Overcoming Isometrics & Instantaneous PAP
The landmine provides another great option not only for performing basic overcoming eccentric isometrics but also for performing more instantaneous PAP protocols as its very easy for the lifter to slip in and out of the safety pin thereby allowing them to transition immediately into the explosive movement. The landmine also provides numerous overcoming eccentric isometric options that many lifters will find more user friendly, less complex, and easier to setup than more traditional barbell variations. Here are more of my favorite variations that include shoulder presses superset with push press, lunges, split squats, chest presses, deadlifts superset with jump squats, and Purmotion versions.
WHY NOT GREATER THAN 70% 1RM LOADING??
Applying too great a load to the overcoming isometric will keep the lifter from being able to push with the same intramuscular intensity against the pins. This is something I've experimented quite a bit with myself and my athletes. Once you start to go beyond approximately 70%, the isometric begins to feel more like a yielding isometric (where the goal is to resist gravity and the urge to drop the weight further) rather than an overcoming isometric (where the goal is to feel like you're trying to break through the pins). It simply begins to feel like a totally different training stimulus from an intramuscular standpoint. The percentage of 1RM at which this occurs will likely vary from person to person.
GENERAL RECOMMENDATIONS AND TRAINING PROTOCOLS
I typically recommend performing 3 sets of 3-4 reps with each repetition using a 3-5 second maximal effort overcoming isometric contraction. However, rather than focusing too much on time per repetition, the goal should be to maximize deep activation and intramuscular tension and pay less attention to the exact duration. Simply, lift by feel. Read more about programming and rep ranges for strength training here.
Finding the Right Position & ROM
When performing overcoming isometrics the lifter should try to find a position anywhere from the moderately stretched position, or 90 degrees, to as high as the highest sticking point (20-30 degrees from lockout) as this allows both high force production and maximal motor unit recruitment to occur. In other words, the goal is to maximize the length tension relationship. Too much or too little overlap of muscles fibers will compromise force production and activation.
So yes, the overcoming isometric should feel powerful and forceful while also producing significant intramuscular tension on the targeted musculature. Lower or higher positions can also be employed periodically to work on specific sticking points that lifters may experience on certain portions of their lifts.
It should also be noted that as long as maximal effort and exertion are used close to, or near maximal levels, of activation will occur in the targeted musculature. With that said, what is likely to change based on the depth or ROM is the targeted muscle(s) that is emphasized.
For instance, performing the overcoming isometric closer to the bottom or 90 degree position of a chest press will likely target the chest and shoulders to a greater extent as well as the outer regions of the pectorals, whereas a higher position will likely target the triceps and inner chest more so with less emphasis on the shoulders. Similarly, an overcoming isometric near the 90 degree bottom position of a squat will likely result in a roughly equal level of quads and glute activation whereas higher positions will likely be predominately quads.
Rest Periods for PAP on Explosive Movements
Although the research is quite mixed with regards to the exact length of rest periods needed to maximize the PAP response, current practice suggests one should rest 2-10 minutes before moving to an explosive activity in order to ensure fatigue accumulation doesn’t outweigh the potentiation response. The stronger you are, the more time you’ll need to allow fatigue to dissipate.
However, waiting longer than 10-15 minutes can cause the potentiation response to gradually dwindle. Many folks will find they need experiment and go through some trial and error testing to figure out the optimal length of time they need to rest and recuperate in order to maximize the PAP response as it is likely to be quite individualized.
Frequency of Implementation
Due to the extreme strain they place on the nervous system and the amount of tension the musculoskeletal system is subjected to, overcoming isometrics should be used somewhat sparingly. As far as the maximum recommended frequency, I generally suggest no more than 3 sets per muscle group, or lift, and no more than once per week per muscle, or lift, as more than this may lead to symptoms of overtraining. However, the implementation of the eccentric isometrics in conjunction with the overcoming isometrics may help prevent overtraining since eccentric isometrics generally help with recovery due to their therapeutic effects.
Solo vs Supersets
While one of the main goals of overcoming isometrics is to elicit a post activation potentiation response in order to produce greater power output on subsequent explosive activities, they can also be performed for other reasons. In fact, the benefits of performing overcoming eccentric isometrics are so numerous that simply performing them as one of the main functional strength and hypertrophy exercises for the day is not only acceptable but beneficial for reasons discussed below.
17 Additional Benefits of Overcoming Eccentric Isometrics
More research is needed but, based on principles of muscle physiology and neurophysiology, there are 17 likely benefits of combining eccentric isometrics with overcoming isometrics. Read more about eccentric isometrics here.
1. Increase proprioceptive feedback and kinesthetic awareness produced by muscles spindles that are primarily activated under loaded stretched conditions. This helps optimize body mechanics, form, and technique. Most overcoming isometric conditions don’t provide such a benefit as in the absence of an eccentric element proprioceptive feedback is limited.
2. Increase ability to recruit high threshold motor units in light of the fact that muscle spindle activation from gamma motor neurons has been suggested to indirectly increase overall motor unit recruitment and neural drive via alpha gamma co-activation.
3. Enhance activation of the stretch reflex which likely contributes to greater force production and power as well as athletic performance.
4. Decrease onset of fatigue associated with pre-stretching the muscle prior to concentric contractions. Studies of muscle fatigue suggest that eccentric contractions and pre-stretch not only help delay the onset of fatigue they also increase force capabilities, both of which are a critical aspect of maximizing potentiation, proprioception and motor programing.
5. Maintain optimal length tension relationship of muscles as the muscles will be lengthening and shortening under tension rather than just shortening.
6. Provide a semi-adjusted strength curve similar to accommodating resistance. Overcoming eccentric isometrics produce an effect similar to that of accommodating resistance protocols such as band resistance, chains, and band assistance (reverse bands). That’s because the bottom eccentric isometric position involves somewhat lighter loads of 30-70% 1 RM while the degree of force and tension produced by the overcoming isometric against the pins (typically at mid range height) are greater than 1RM provided the individual is using maximal exertion during the overcoming isometric as they should be.
7. Allow the eccentric isometric and overcoming isometric to work synergistically. In essence, the eccentric isometric helps wake up additional motor units via pre-stretch and alpha gamma co-activation associated with muscle spindle activation. This produces a stronger and more forceful overcoming isometric with greater motor unit recruitment and force production and ultimately leads to greater potentiation. The greater potentiation then feeds right back into the eccentric isometric allowing greater co-contraction of agonists and antagonist muscles thereby enhancing the slingshot effect.
8. Enhance the power and force used to drive against the pins and move into the overcoming isometric as the eccentric isometric acts as a recoil or reloading of the muscles, much like a slingshot, as opposed to driving hard into the pins from a standstill position without pre-stretching/pre-loading the muscles before hand. In fact, the athlete should feel that the eccentric isometric hold makes the overcoming isometrics feel more locked in and more powerful not only because of the delayed fatigue associated with pre-stretching but also because of the previously mentioned reloading effect.
9. Improve muscle growth and hypertrophy. Overcoming eccentric isometrics involve all 3 mechanisms of muscle hypertrophy including mechanical tension, muscle damage, and metabolic stress. Traditional overcoming isometrics involve only 2 of these mechanisms namely mechanical tension and metabolic stress.
10. Produce greater post activation potentiation by reducing fatigue as the ability to balance activation and fatigue appears to be one of the most critical components for maximizing PAP.
11. Prevent autogenic inhibition, i.e. the neurologic inhibitory response produced by Golgi tendon organs in response to excess tension on tendons. Activation of muscle spindles has been shown to potentially offset this effect since these mechanisms are polar opposites. In other words, they cannot occur simultaneously at high levels due to the fact that activation of intrafusal fibers/muscle spindles would override the inhibition from Golgi tendons organs given muscle spindles have faster conducting axons than Golgi tendon organs.
12. Help optimize proprioception on the subsequent eccentric isometric likely contributing to an improved ability to fine-tune body positioning on that eccentric isometric by increasing muscle stiffness as proprioceptive feedback is strongly dependent on the ability to maintain high levels of intramuscular stiffness.
13. Improve ability to co-contract reciprocal muscle groups (agonist and antagonists) during the eccentric and eccentric isometric phases, a critical component of eccentric contractions, as a result of the high levels of muscular stiffness produced from the prior overcoming isometric.
14. Enhance motor control and stability on the eccentric and eccentric isometric phases. These elements have been shown to be directly linked to co-contraction of reciprocal muscle groups which, as noted above, are enhanced by the prior overcoming isometric.
15. Produce greater neural drive, force, and power output on the subsequent overcoming isometric as eccentric induced co-contraction contributes to greater reciprocal inhibition and firing of the agonists on that subsequent concentric contraction/overcoming isometric.
16. Reinforce greater levels of maximal effort and maximal intensity muscular contractions on both ends of the movement as the overcoming isometric and the eccentric isometric help feed off each other since both are intended to be maximal exertion regardless of the load. In fact many individuals have difficulty with the notion that eccentric isometrics are intended to be maximal effort in the bottom or 90 degree stretched position as the lifter should be using maximal effort to create as much co-contraction as possible by squeezing into the movement with their reciprocal muscles. The max effort overcoming isometric helps create a max effort mindset that translates to maximal exertion eccentric isometrics with very high levels of co-contraction.
17. Provide high intensity training options with maximal exertion that are very joint friendly and low impact since light to moderate loads can be effectively employed while still producing a strong training stimulus.
Read more about eccentric isometrics in my book MOVEMENT REDEFINED.
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