Selecting Exercises at the Gym - What's "Optimal" ?

Pre-Selection and Experimentation

Before diving into the principles of selection, it has to be stated that any exercise that is to be implemented in a program has to be both though out from before as well as attempted in a session to validate it's use. An exercise being thought out from before refers to the phenomenon of people selecting exercises purely based on biomechanics principles as well as other evidence-based information. This is a great way to go about selecting exercises, but should not serve as the exclusive method of selection. No exercise can be regarded as suitable for the individual only by general recommendations and guidelines if it is not tested and evaluated practically. Therefore, when an exercise is pre-selected, it is of high importance to then test it out in practice and alter accordingly to your needs. If there's shoulder pain using a more, in theory, suitable grip, then change it. If there's low muscle perception using a more "optimized" elbow angle, then change it. If your mobility is limited using a certain foot placement, change it! The point here is that it is delusional to blindly follow exercise recommendations completely based on the literature if the individual perception is not regarded at all. This actually takes away from the optimal-based approach rather than following it.

Exercise Selection Guideline

The first principle of exercise selection is the guideline of selecting exercises. Here we are able to use the evidence we have available to create a set baseline of commands that allow for irrelevant exercises to be filtered out and for the more relevant ones to be at our disposal.

1. Limiting Factor

The limiting factor of an exercise simply refers to the muscle group that has the highest degree of contribution during an exercise, and will hence limit the set from being continued when the relevant muscle group has reached muscular failure. When performing the bench press for the chest, the exercise should be limited by the chest muscles and not the triceps, although the triceps will still contribute. If you are performing an exercise aiming to target a specific muscle group but are being limited by another, then you might have to reconsider your technique or switch the exercise.

2. Range of Motion

The evidence here is clear. “Full Range of Motion” is better. When referring to full range of motion it is usually translated as working through long muscle lengths aka maximizing the stretched position. Using the example of the bench press for the chest, it will be more beneficial for hypertrophy if you allow the bar to touch your chest than not do so. When selecting an exercise make sure that 1. It allows for you to reach long muscle lengths, and 2. The length at which the targeted muscle group is trained at, is maximized ( during the stretch ) as much as possible.

3. Stability

The factor of stability heavily links back to the principle of specificity. When training for muscle growth the goal is to grow muscle. Therefore, when performing an exercise it should be ensured that you do not fail a set or stop the exercise because of instability. When performing a bench press for the chest do not have your legs raised up but rather have them planted on the ground to ensure stability.

4. Standardization

Any exercise being performed must have a high degree of standardization applied to it. This is because 1. It allows for greater tracking accuracy over the weeks and 2. Minimizes technique deterioration over subsequent sessions. The best way to perform this is by including pauses in your exercises such as at the bottom of the squat or the bench presses, locking out (safely) at the top of the movements, and including a tempo for the negative portion of the repetition (it is important that the tempo is only set for the negative/descending part as maximal effort should be applied during the concentric portion), preferably 2-3 seconds. When using the bench press for the chest it would be appropriate to include a pause when the bar touches your chest, a (smooth) lockout of the elbows at the top, and a controlled eccentric portion lasting around 2-3 seconds.

After applying these guidelines you have most likely now filtered down to a number of exercises that are deemed as suitable. So, where do you go from here? Since there are likely a number of exercises you can still choose from there can be a number of factors, based on your own individual perception, that will finalize your exercise selection.

Individual Perception Factors

1. Mind-Muscle Connection

The mind-muscle connection refers to your ability to feel/perceive the targeted muscle being worked during the set. There is some evidence pointing to the fact that the use of mind-muscle connection may indeed enhance hypertrophy. Despite the evidence, the use of it as a perception factor acts slightly differently. When performing a given exercise the degree to which you can feel the targeted muscle being worked can indicate, to some extent, how well suited an exercise is for you. When selecting exercises make sure there is a decent mind-muscle connection of the targeted muscle. It is also important to note that the mind-muscle connection will likely improve over time when performing the same exercise.

2. The Pump

The pump is a common phenomenon that almost all trainees experience at one point at the gym. The pump refers to the swelling of the muscle during exercise, usually described by a “skin-tearing” feeling. Again, there is quite a bit of evidence that the pump may act as a factor contributing to hypertrophy and has also been proposed by Brad Schoenfeld as one of the 3 mechanisms of hypertrophy (metabolite accumulation) in his famous 2010 paper. Despite the strong evidence we have that the pump may indeed be a mechanism of hypertrophy, the use of it as an exercise perception factor acts as one of the ways to determine the effectiveness of a given exercise. Exercises that allow you to gather a good pump of the targeted muscle group may very well indicate that they are worthy of a selection in your workout program. On the other hand, if an exercise gets you no pump of your targeted muscle group and you instead experience a pump on secondary muscle groups, although not necessarily, it may be worth reconsidering the use of a given exercise. Again, it is important to note that the pump is only one of a few indicators and should not be used as an indicator in isolation since it can be manipulated based on many things (Carbohydrates, Sodium, Resistance Curve, etc.).

3. Pain

The final perception factor is rather simple. Pain here refers to the degree of discomfort felt in the targeted muscle or relevant connective tissues when performing an exercise. No matter whether an exercise is deemed as “safe” or “low-risk”, if noticeable pain is experienced by the trainee it might be worth switching to a different exercise or the variation of the given exercise.

Factors Influencing Perception Factors

Perception Factors can be changed depending on a number of factors. Prior to quitting on an exercise it might be important to experiment with these factors so as to optimize your perception factors.

1. Repetition Range

The repetition range in which an exercise is performed under can influence the perception factors pretty significantly. The best examples we can use are probably stiff-legged deadlifts and dumbbell lateral raises. Stiff-legged deadlifts are commonly low on the perception factors scale when executed under too high of a repetition range, such as 10-20 or 20-30. This may likely be due to other secondary muscles coming in to play over the course of a set, such as the spinal erectors, lower back, and forearms. On the other hand, a repetition range of 5-10 seems to rank higher on the optimal scale. In contrast, Dumbbell Lateral Raises usually have the best feeling when operated under higher repetition ranges such as 10-20 or 20-30. When performed in the 5-10 repetition range, it is common to experience shoulder pain and low pump, making it less suitable of an exercise. Therefore, make sure to use the repetition range that optimizes the perception factors. The actual number of repetitions is irrelevant in regards to muscle hypertrophy as what seems to matter is the proximity to failure. It is then wise to choose a repetition range solely based on how the exercise feels.

2. Joint Angles

Joint angle is self-explanatory. At what angle is a relevant joint going to be placed at during a certain movement. For instance, many people find that pressing with an elbow angle of 45 degrees is a lot less pain-inducing for the shoulders relative to something closer to a 90 degree angle. Similarly, squatting below a 90 degree knee joint angle will likely result in a greater mind-muscle connection, relating to the quadriceps, due to the greater stretch induced. The key here is to manage relevant joint angle so that the 3 perception factors are optimized. Usually the perception factor that is largely dependent on joint angle is pain. Test an exercise for yourself. Alter the relevant joint angles so that the guidelines are still in place and the perception factors can be enhanced.

3. Cadence

Cadence, also known as repetition tempo, is the final factor which may influence the perception factors. When referring to cadence, we are mostly speaking about the eccentric part as it is probably best to exert maximum effort during the concentric portion rather than having a fixed tempo. Introducing more controlled eccentrics, as well as a pause, may increase individual perception factors. Again, it is important to note that direct evidence on this particular topic is inconsistent. Some evidence shows that repetition tempo may not be a significant enough factor when it relates to muscle growth whereas other indicates that slower eccentrics may be beneficial for hypertrophy. This is just a recommendation that can be applied to assess whether the exercise perception factors can be positively affected.

Resistance Curves

Resistance Curves have also been a relevant topic of discussion in the subject of exercise selection. A Resistance Curve is the change in difficulty experienced at different parts of an exercise's repetition. There are 4 types of resistance profiles.

1. Ascending

Most Difficult at the start of the concentric portion. A good example of this are squats.

2. Descending

Most Difficult at the end of the concentric phase. Lateral raises are an example of this.

3. Parabolic

Most Difficult in the middle of the repetition.

4. Flat

Similar difficulty throughout the range of motion.

Why are resistance profiles important and what is the ideal resistance curve to use? There is evidence alluding to the fact that matching the resistance curve of an exercise to the strength profile of a muscle may lead to greater hypertrophy. This means that using a resistance curve to match where the muscle is at it's strongest (where the greatest amount of cross-bridge formation occurs) will be the greatest potential option. Despite this idea, there are great limitations preventing it's practical use. A large majority of the time, altering the resistance curve of an exercise to match the strength profile of a muscle can be difficult to do. It is also important to mention that the findings we have are still far from conclusive. Therefore, the best way to approach things in regards to resistance curves is by only altering the resistance curve of an exercise to match the strength profile of a muscle when it is easy to do so as it may slightly improve gains.

Additional evidence also suggests that different resistance curves are likely to induce similar adaptations in hypertrophy. This reinforces the idea that focusing on resistance profiles likely provides marginal to no benefits for hypertrophy. It is likely more important to train at longer muscle lengths in general than additionally focusing on which part the exercise is hardest at.

Long muscle lengths

Applying everything that has been touched upon so far will probably be enough for you to finalize your exercise selection. The truth is that distinguishing between exercises on minute details will probably not yield any more significant results. If you are to walk away from this article with only one thing in mind is the idea of training through long muscle lengths. Studies on range of motion and hypertrophy are pointing towards one direction which seems to be that training through a full range of motion is better than training through a shorter range of motion. This likely doesn't have to do with the actual range of motion, because full ROM is always different depending on many things, but with the muscle length that you're training at. Longer muscle lengths are what seem to be the determining factor in the range of motion. Training through these long muscle lengths, which are usually characterized by a deep stretch of the muscle, is superior than training through short muscle lengths. A recent systematic review and meta-analysis by Wolf et al. supports this idea as, interestingly enough, partials at long muscle lengths induced greater hypertrophy than both full ROM and short muscle lengths. Now, the issue with partials at long muscle lengths is the ability to standardize the technique and ROM over time, violating a principle of the exercise guidelines we mentioned. This is the reason why full ROM seems to serve a good default approach for most people as it has the ability to combine the evidence we have available as well as a simple practical approach.

What about EMG?

If you happen to be even slightly familiar with resistance-training research you might bring up the question of "what about EMG data?". EMG has served as the bread and butter of biomechanics for a very long time. It simply refers to muscle activation during a given exercise. Now, EMG may very well require an article on its own but for the time being I will try to break things down as simple as I can. EMG, although not always, seems to be getting less and less relevant as an indicator of exercise effectiveness over time. Whilst a few years ago it seemed that EMG data were treated as gospel, a recent publication by Vigotsky et al. explains why this may not be the case. Simply put, it seems that EMG data may not be valid for predicting long-term muscular adaptations.

Where to go from here

Piecing everything together we can come up with the following strategy to help us select exercises for each muscle group that is to be trained.

1. Filter out irrelevant/non-suitable exercises using the exercise selection guideline.

2. Choose the most appropriate exercises from the ones you now have available to your disposal depending on your own individual perception factors. Use a rep-range which maximizes the perception factors of each exercise without violating the guidelines.

3. Alter the resistance curve of the exercise to match the strength profile of the muscle only when it is easy to do (OPTIONAL)

4. Include partials at long muscle lengths when it is easy to standardize technique and ROM (OPTIONAL)

Nuances of exercise selection

No matter how simple we try to break things down, a bunch of questions will likely both remain and form. Our aim at FarsHub is to make fitness as simple as possible based on scientific findings as well as anecdotal experience. There are still many nuances when it comes to the topic of exercise selection. Whilst the topic of exercise selection is still relatively fresh in the field of sport science, we have evidence to provide us the confidence with which we implement this strategy to all our clients with a large degree of success. If the evidence shifts or new findings are published, which may contradict the current literature, then this article will be updated accordingly and our strategies re-evaluated, but for the time being, the "optimal" scale remains extremely broad.