Does Size = Strength? - The Muscle PhD

Does Size = Strength?

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Introduction

Welcome to what should be a fun and exciting article for all of us. This is a common question we’ve all had pop into our heads – is a bigger muscle a stronger muscle? If someone has bigger quads than you, can they squat more weight than you? If a bro has massive pecs, can he bench a forklift? You get the idea.

At face value, this would seem like a pretty simple question. We’d immediately assume that the answer to most of these queries is a resounding “yes,” but unfortunately, it can be a little murkier than that. So, as we do so often around here, let’s get into the details.

How do we get Stronger?

First, we need to discuss how we get stronger. There are a lot of adaptations that take place when you start lifting weights. The general order of these adaptations is a little out of the scope of this piece, but it’s obvious (and accepted) that neural adaptations begin almost the second you pick up a weight.

If you’ve ever taught someone how to perform a lift, you’ll know what we’re referring to. Their first few reps are a little rough and shaky, the next few look okay, and last few keep getting better. One or two more cues and their form becomes pretty consistent over the next few sets. That is instantaneous motor learning and is also why we typically recommend getting your form as solid as possible right away. The more reps you perform with great technique, the better your motor learning experience and the more ingrained that proper pattern becomes (Schmidt & Wrisberg, 2008).

Intriguingly, motor learning contributes to strength quite a bit. You see, when we test strength, we’re oftentimes constrained to some sort of test that’s a little complicated for most folks; many studies utilize a 1RM on the squat or bench press to assess strength. Unfortunately, both of these movements inherently involve quite a bit of skill. For folks with minimal experience, simply learning the exercise will almost instantly boost strength. In fact, McCurdy et al. (2004) found that subjects immediately improved their 1RM on a novel exercise by 4.7% after a single testing session.

Motor learning falls under the umbrella term of “neuromuscular adaptations.” These are adaptations that are primarily localized in the brain, spinal cord, and motor neurons – in exercise science, we generally consider this to be the central nervous system. We include “muscular” in neuromuscular because these adaptations can affect factors like muscle activation, agonist/antagonist inhibition, rate coding, and so forth. Let’s cover those in more detail.

  1. Muscle Activation: this one is somewhat self-explanatory. In order to get stronger, we need to recruit more muscle fibers. When we recruit more muscle fibers, we (typically) see an increase in muscle activation. More active fibers = more force production = more strength! Usually, we measure muscle activation against some sort of standard figure. More recent research has employed the use of either maximal isometric contractions or maximal involuntary contractions – then we can report dynamic contractions as a percentage of either. As you gain training experience, your ability to recruit your muscles improves and we usually see an increase in voluntary muscle activation – especially in certain muscles compared to others. We’ll touch on that in a bit.
  2. Agonist/Antagonist Inhibition: When we start lifting weights, we perform movements and/or produce force(s) that our body isn’t used to. In turn, a likely protective mechanism occurs in which we actually activate the opposing (antagonist) muscle during an exercise. An easy to visualize example is a leg extension exercise. Obviously, we’re targeting the quads, right? However, multiple studies have shown that the hamstrings are also activated during leg extensions which might confer some sort of protective benefit for the knee joint (Cresswell & Overdal, 2002; Kingma et al., 2004). While antagonist activation is likely necessary for reducing injury risk and/or providing joint stability, reducing this activation is one reason we get stronger. Imagine your first week of training; 100lbs on leg extensions might have felt pretty tough, right? However, just a few weeks down the road, they’re not nearly as hard. While other adaptations certainly took place, your hamstrings also got out of the way!
  3. Rate Coding: Essentially, rate coding refers to how quickly your motor neurons can “fire,” – or, more scientifically, how quickly they can fulfill an action potential (Enoka & Duchateau, 2017). This adaptation is likely more prevalent with power training or sprint training in which gains take place at high velocities. For the most part, muscle force is controlled by both motor unit recruitment (activation) and rate coding, however, high velocity contractions are generally more dependent on rate coding (Enoka & Duchateau, 2017). Regardless, rate coding can still certainly play a role in strength gains – have you ever tried to lift a heavy weight slowly? No, of course not; maximum velocity should always be the intention. Previous studies have also shown that strength training induces a greater increase in rate coding than endurance training (Vila-Cha et al., 2010) which underscores the role rate coding plays in strength adaptations.
  4. Motor Unit Coordination: We’re also going to cover motor unit coordination as it’s highly related to motor learning. In essence, motor unit coordination discusses how muscle groups and even neuromuscular compartments of individual muscles “team up” to produce force and, ultimately, movement. Very rarely do we have a single muscle performing a joint action – especially when considering the major muscles that we train in the gym. For instance, when we perform curls, we’re not just training the biceps. In fact, we’re also training the brachialis, brachioradialis, and most of the forearm flexor muscles – not to mention the triceps and shoulder muscles involved in stabilizing the upper arm. Intricate coordination of the motor units between these muscles is necessary for successful elbow flexion (curling motion) and the order of firing is dependent on both the task and the unique mechanical advantage of each muscle at each degree of range of motion (Brown et al., 2007). All-in-all, strength training results in a more “efficient” motor unit coordination pattern that supports safer, but also more powerful, movements.
  5. Hypertrophy: Lastly, muscle growth can also increase strength. Muscle growth via weight training involves a large portion of myofibrillar hypertrophy, which refers to the addition of myofibrils (contractile proteins) to a muscle fiber. Over time, this obviously leads to a bigger muscle, but the increase in contractile proteins should also increase force production. It is generally well accepted that a relationship exists between myofibrillar hypertrophy and strength (Taber et al., 2019), however, the degree and strength of this relationship isn’t well-understood and has caused some other researchers to question this connection (Loenneke et al., 2019). We’ll get into that more in a minute.

Hopefully you made it through that dry discussion – I promise it should get more interesting here soon! Above is a brief refresher on the major neuromuscular adaptations to strength training that influence strength. Ultimately, strength is a skill that needs to be trained appropriately. And, yes, muscle growth probably influences strength at least a little bit. Before we can discuss that, though, let’s cover some boring statistics methods so we can better understand how scientists are doing all this nerdy stuff.

Statistically Defining Strength Gains

Obviously, many studies define strength as a 1RM on a given exercise, but they can also utilize unique devices to measure peak muscle force or torque. Regardless, research has now gotten to the point where we’re trying to explain or measure how and why people get stronger. Essentially, we want to know, “what role does each training adaptation play in overall strength gains?”

To answer that question, we need to cover some basic statistics. We’ve probably all heard the phrase, “correlation isn’t causation,” right? Well, that’s certainly true. However, strong correlations can certainly help tell a story, especially in situations where you expect to see them. For instance, we’d generally assume that an increase in muscle size would align with an increase in strength, right? Well, to truly define that, we often calculate what’s called a “Pearson correlation coefficient” which gives us an r value. This r value suggests both the direction and strength of a correlation. A positive number dictates a positive relationship; as one variable goes up, so does the other. A negative number, on the other hand, represents a negative relationship in which a variable increasing results in another decreasing. The overall “strength” of the correlation is dependent on the number itself, rated on a scale of 0-1 or 0-(-1). 1, or -1, represent perfect correlations; as variable A increases by X, variable B increases/decreases by an exact factor of X with perfect consistency.

Stick with me, we’re almost there. With this sliding scale in mind, we typically rank r values as:

  • 0 – 0.1: No relationship – these variables are not related
  • 0.1 – 0.3: Weak relationship – AKA, nothing to write home about
  • 0.3 – 0.5: Moderate relationship – now this is kind of interesting
  • 0.5 – 1.0: Large relationship – now this is VERY interesting

To keep things simple, many studies like to calculate the correlation between a given trait and overall muscle strength. For instance, one study from Akagi et al. (2014) found a correlation of r = 0.866 between pectoral muscle size and bench press 1RM. That’s a huge relationship! Similarly, studies have shown that VO2 max has a negative correlation with race times, at a tune of r = -0.757 (Alvero-Cruz et al., 2019). Remember, though, a negative relationship isn’t necessarily a bad thing – as VO2 max goes up, race times go down (get better)!

With this in mind, let’s take a look at what other research projects have shown in respect to muscle size and strength.

Does Size = Strength?

In short, multiple studies have found large correlations between muscle size and strength or performance:

  • Akagi et al. (2009) found a correlation of r = 0.564 between muscle volume and peak torque of the biceps. Biceps cross-sectional area (CSA) was also related to maximum force to the tune of r = 0.637.
  • Abe et al. (2016) measured the muscle thickness of toe flexor muscles (no, really) and examined the relationship between how jacked people’s toes were and their walking speed. Interestingly enough, all variables measured showed an r value of at least 0.553, suggesting a rather impressive relationship between toe flexor muscle thickness and walking speed.
  • Evangelidis et al. (2016) measured hamstrings muscle volume and hamstrings peak torque and found a strong (r = 0.69) relationship between the two.
  • Erskine et al. (2014) uncovered a pre-training correlation of r = 0.787 between biceps volume and biceps curl 1RM. We’ll touch more on this study in a minute.
  • I recently ran through the raw data of a bench press pilot study we did in the past. We’ll get into that more in another article, but I did find a strong correlation of r=0.6659 between pec thickness and bench press 1RM and an r value of 0.6929 between triceps thickness and bench press 1RM.
  • Okay, you get the idea. Let’s move on.

Now, to make things a little more boring (but also interesting, right?), we can now calculate the coefficient of determination by using some sort of regression equation. Essentially, this statistical method explores how much variance in variable B can be explained by changes in variable A. More specifically, what percentage of strength gains could be explained by a change in muscle size?

While there are multiple types of regression that are way outside the scope of this piece, many linear relationships just square the r value from the Pearson’s correlation calculation. Since we often assume muscle size and strength to be somewhat linear (a bigger muscle should be stronger, right?), this method is occasionally used in the literature. For instance, the Evangelidis et al. (2016) study calculated an r2 value of 0.48 from their r = 0.69 relationship between hamstrings size and peak torque. This would suggest that hamstrings size explains about 48% of the strength of the hamstrings. This is the simplest way to perform this calculation; many other studies employ some sort of multiple regression formula that includes all variables and their respective contribution to strength gains. We could also get into the potential non-linearity of this relationship, but frankly, I think everyone is bored enough as it is.

Now, we can ask the ultimate question: is a bigger muscle a stronger muscle? Well, from the previously mentioned handful of studies, we do see a strong correlation between muscle size and strength. Additionally, we have at least two studies showing strong correlations between muscle growth and strength gains – now this is cool!

Balshaw et al. (2017b) examined a group of men performing leg extension training. After the training period, they measured things like muscle activation and muscle size and attempted to correlate these adaptations with the observed increase in quadriceps strength. What did they find? Well, the change in quadriceps size had a correlation of r = 0.461 with the increase in strength whereas the change in muscle activation was correlated with strength gains with a value of r = 0.576. The authors did a slightly different calculation for the coefficient of determination that we discussed above, but they did find that the change in muscle size explained 18.7% of strength gains whereas the change in activation accounted for 30.6% of strength gains.

Erskine et al. (2014) performed a similar experiment but with biceps training. These researchers also measured muscle size and activation and attempted to describe the relationship between those adaptations and strength gains. Intriguingly, a strong correlation was found for the relationship between muscle growth and strength (r = 0.527) but not for the relationship between changes in muscle activation and strength (r = 0.187). Via simple linear regression, these data would suggest that hypertrophy accounted for 27.7% of strength gains in the biceps whereas changes in EMG only supported 3.5% of strength gains.

Now, it’s important to admit that we do have other studies examining this topic or ones that at least circle the drain on the subject of size and strength relationships. However, some are a little older and used less advanced measurements on muscle size or they didn’t use much weight during training which resulted in muscle growth but not great strength gains (Erskine et al., 2014; Loenneke et al., 2019). It’s pretty well-understood that strength is a skill and training with heavier weights is more effective for promoting strength gains than lighter weights (Campos et al., 2002), so I don’t think we need to lean on those studies too heavily.

Unfortunately, though, due to the relative dearth of information on the topic, some researchers have proposed that there is a negligible relationship between muscle size and strength (Loenneke et al., 2019). The authors cite the lack of direct research examining different levels of growth and their correspondence to strength gains. While I can’t think of a study directly looking at this causal relationship either, I can think of several studies in which a subject group gained more muscle than their counterparts and also gained more strength (Campos et al., 2002; Cribb & Hayes, 2006; Mangine et al., 2015; Willoughby et al., 2007; + many more). Again, we just discussed the different ways strength can be developed, but there’s a good deal of indirect evidence showing that muscle growth probably influences strength to a degree.

While it’s fun to come up with various studies that indirectly answer questions, I think we can put forth a novel hypothesis that might help direct future research questions.

Size Might = Strength… Sometimes?

Up to this point, we’ve covered how a muscle gets stronger. And a few studies have shown that muscle growth can influence strength gains. Aaaaaand, in the two specific studies above (Balshaw et al., 2017b & Erskine et al., 2014), we see something interesting. Biceps hypertrophy did correlate with strength gains, but changes in biceps activation did not. Conversely, quadriceps growth and activation gains both correlated with quad strength. What’s the deal here?

My shower thought theory is that these unique adaptations might be dependent on an inherent trait of each muscle: voluntary activation.

Our muscles can be activated voluntarily or involuntarily. Voluntary activation is just as it sounds – you cause the muscle contraction, either by flexing as hard as possible or using an isometric device that resists joint rotation during a maximal contraction. On the flip side, involuntary activation is generally stimulated by an electrode device that can actually maximally stimulate a muscle. There are a few reasons why we can’t maximally activate a muscle voluntarily, but those are outside the scope of this piece. Ultimately, we measure the voluntary activation rate of a muscle as a percentage of its maximal involuntary activation.

Okay, so what’s this mean? Gen-er-a-lly, smaller muscles can be voluntarily activated to a higher degree than large muscles – this is a broad idea, not a law, hence the careful spelling out of “generally.” An easy way to differentiate the two (generally, again) is that the major upper body muscles are usually smaller than the major lower body muscles. Regardless, our article on training frequency (here) goes into voluntary activation for every muscle group, but since our specific example here is about the biceps and quadriceps, we’ll stick to those. In short, the biceps can voluntarily achieve at least 95% of their maximal involuntary contraction whereas the quads are closer to 85% (Behm et al., 2002). What does this mean?

Well, my hunch is that muscles with lower voluntary activation rates might be more dependent on neuromuscular adaptations than hypertrophy for strength gains. On the flip side, muscles with higher voluntary activation percentages could be more reliant on growth for strength gains since muscle activation is already near maximal levels. Where might we see anecdotal evidence of this?

If you ever watch training videos of elite bodybuilders and powerlifters you might notice something. The top bodybuilders all bench around 500lbs, right? The best raw powerlifters (that do all three lifts, anyways) also bench around 500-550lbs. Essentially, similar bench press strength between elite bodybuilders and powerlifters.

However, how much do the best bodybuilders squat? 6, maybe 700 pounds if they train heavy more often? Now take a peek at the top powerlifters – these guys are squatting 800, 900, and now even 1000lbs raw! MASSIVE differences in squat strength.

Another anecdote since we’re on a roll here – when I first started powerlifting I had only trained as a bodybuilder for previous 4-5 years. In my first competition I bench pressed 319lbs in the 181 class – not impressive by any means, but this was the top bench in the Junior (20-23) age category by a long shot (most were benching 250-280lbs). In fact, the current USPA record for bench press in the 181 class for the Junior 20-23 group is 413lbs – I wasn’t far off (relative to the squat and deadlift) and had no idea! Mind you, that’s the most current record and was set in 2019 – I was in the 20-23 category well before that record was set, putting me even closer than I knew at the time. Long [boring] story short, my bench press was much more competitive than my squat and deadlift and I had only ever trained upper body like a bodybuilder. Makes you think…

Back to science now. Could these observations be due to muscles with high voluntary activation rates being more dependent on growth for strength? Could this also explain why a powerlifter with relatively smaller quads can out-squat a bodybuilder with larger quads? One intriguing master’s thesis somewhat answers this question. DiNaso (2003) examined Olympic weightlifters, powerlifters, and bodybuilders and assessed their thigh muscle area and relationship to squat 1RM. Interestingly, all three groups exhibited similar thigh muscle areas, but both powerlifters and Olympic lifters could squat significantly more than bodybuilders. Ultimately, the relationship between thigh muscle area and squat 1RM was a meager r =0.20. However, recall the aforementioned Akagi et al. (2014) study in which pectoral size had a very strong (r = 0.866) relationship with bench press 1RM. Something very interesting could be going on here.

Another fascinating study from Schoenfeld et al. (2016) had two groups perform either heavy (2-4) or moderate (10-12) weight training for both the upper and lower body for 8-weeks. Intriguingly, all subjects made similar gains in muscle thickness, but squat 1RM increased significantly more in the heavy group than moderate group (30% vs 16.8%). Admittedly, the heavy group also made visually better bench press strength gains than the moderate group (14.4% vs 10.5%), but the difference was not statistically significant, thus necessitating the need for further research. Regardless, this study certainly lends potential support for the hypothesis that lower body muscles are generally more reliant on neuromuscular gains whereas upper body muscles could be more reliant on size gains when it comes to strength.

On the flip side, another fun study from Mangine et al. (2015) explored a similar training program to Schoenfeld et al. (2016). These subjects performed either heavy (3-5 reps @ 90%) or high volume (10-12 reps @ 70%) upper and lower body training and had muscle size and strength measured before and after training for 8 weeks. Intriguingly, the heavy group made better bench press gains (13.7% vs 6.1%) but also gained more lean mass in their arms (5.2% vs 2.2% increase) whereas the heavy and high volume squat groups made similar hypertrophy and strength gains from both programs. If anything, this helps support the notion that upper body muscles are reliant on growth for strength, as the group that made better size gains also made better strength gains. However, this definitely muddies the theory that lower body muscles aren’t as dependent on size for strength.

It’s worth mentioning that the wealth of rep ranges and strength studies have been performed on lower body exercises (usually leg extensions or leg press) which has driven our understanding of heavy training leading to better strength gains. However, we definitely need more information on how this relates to upper body strength, and if muscle size is more important for the upper body strength. All-in-all, keep in mind that strength is a skill, and training heavy is more specific to a 1RM test which certainly can influence the results we see in these studies.

Ultimately, this hypothesis is somewhere between scientific theory and outright conspiracy theory. We don’t have much direct data to draw from and the rest is pretty much just observational and/or anecdotal. However, we often make theories based on observations, so it certainly could make sense that muscles with relatively low voluntary activation require more neuromuscular adaptations to get stronger where muscles with higher voluntary activation percentages might be more dependent on growth.

The Takeaway

Now, we won’t leave you hanging wondering which is which. Again, we cover this more in-depth in our training frequency article (here), but the muscles with lower voluntary activation rates are the quads (Behm et al., 2002), abs (Ertman et al., 2016), and glutes (Fisher et al., 2016). On the other hand, muscles with high (≥ 95%) voluntary activation rates include the calves (Crouzier et al., 2018), hamstrings (Baumert et al., 2019), traps (Bech et al., 2017), biceps (Behm et al., 2002), and triceps (Cheng et al., 2010). Unfortunately, we don’t have information on the shoulders, pecs, or lats, but due to their size, we can theorize all three are probably higher than 95%, but we’re not sure on that yet.

So, all-in-all, the main takeaway is that you might need to do some heavier training for lower body movements if strength is your goal due to the voluntary activation percentages of the quads and glutes. On the flip side, if you want a massive bench press, you might not have to train like a powerlifter; hypertrophy training will probably do the trick for building a massive press. Importantly, though, if you are a competitive powerlifter, I’d still do quite a bit of heavy work so you can get used to moving heavy weights – AKA, you know, the thing you compete in?

As with any scientific theory, we’re still molding this one and mulling it over during every moment of boredom. Frankly, this hypothesis was actually birthed in the shower during one of those classic “shower thoughts” moments. When you get this passionate about a topic, this is what happens. You’ll spend your entire shower thinking about how to get stronger. What a life, huh?

References

  1. Abe, T., Tayashiki, K., Nakatani, M., & Watanabe, H. (2016). Relationships of ultrasound measures of intrinsic foot muscle cross-sectional area and muscle volume with maximum toe flexor muscle strength and physical performance in young adults. Journal of Physical Therapy Science, 28(1), 14-19.
  2. Akagi, R., Takai, Y., Ohta, M., Kanehisa, H., Kawakami, Y., & Fukunaga, T. (2009). Muscle volume compared to cross-sectional area is more appropriate for evaluating muscle strength in young and elderly individuals. Age and Ageing, 38(5), 564-569.
  3. Akagi, R., Tohdoh, Y., Hirayama, K., & Kobayashi, Y. (2014). Relationship of pectoralis major muscle size with bench press and bench throw performances. The Journal of Strength & Conditioning Research, 28(6), 1778-1782.
  4. Balshaw, T. G., Massey, G. J., Maden-Wilkinson, T., & Folland, J. P. (2017a). Muscle size and strength: debunking the “completely separate phenomena” suggestion. European Journal of Applied Physiology, 117(6), 1275-1276.
  5. Balshaw, T. G., Massey, G. J., Maden-Wilkinson, T. M., Morales-Artacho, A. J., McKeown, A., Appleby, C. L., & Folland, J. P. (2017b). Changes in agonist neural drive, hypertrophy and pre-training strength all contribute to the individual strength gains after resistance training. European Journal of Applied Physiology, 117(4), 631-640.
  6. Baumert, P., Temple, S., Stanley, M. J., Cocks, M., Strauss, J. A., Shepherd, S. O., … & Erskine, R. M. (2019). Neuromuscular fatigue and recovery after strenuous exercise depends on skeletal muscle size and stem cell characteristics. BioRxiv, 740266.
  7. Bech, K. T., Larsen, C. M., Sjøgaard, G., Holtermann, A., Taylor, J. L., & Søgaard, K. (2017). Voluntary activation of the trapezius muscle in cases with neck/shoulder pain compared to healthy controls. Journal of Electromyography and Kinesiology, 36, 56-64.
  8. Behm, D. G., Whittle, J., Button, D., & Power, K. (2002). Intermuscle differences in activation. Muscle & Nerve, 25(2), 236-243.
  9. Brown, J. M. M., Wickham, J. B., McAndrew, D. J., & Huang, X. F. (2007). Muscles within muscles: Coordination of 19 muscle segments within three shoulder muscles during isometric motor tasks. Journal of Electromyography and Kinesiology, 17(1), 57-73.
  10. Campos, G. E., Luecke, T. J., Wendeln, H. K., Toma, K., Hagerman, F. C., Murray, T. F., … & Staron, R. S. (2002). Muscular adaptations in response to three different resistance-training regimens: specificity of repetition maximum training zones. European Journal of Applied Physiology, 88(1), 50-60.
  11. Cheng, A. J., & Rice, C. L. (2010). Voluntary activation in the triceps brachii at short and long muscle lengths. Muscle & Nerve: Official Journal of the American Association of Electrodiagnostic Medicine, 41(1), 63-70.
  12. Cresswell, A. G., & Overdal, A. H. (2002). Muscle activation and torque development during maximal unilateral and bilateral isokinetic knee extensions. Journal of Sports Medicine and Physical Fitness, 42(1), 19.
  13. Cribb, P. J., & Hayes, A. (2006). Effects of supplement-timing and resistance exercise on skeletal muscle hypertrophy. Medicine & Science in Sports & Exercise, 38(11), 1918-1925.
  14. Crouzier, M., Lacourpaille, L., Nordez, A., Tucker, K., & Hug, F. (2018). Neuromechanical coupling within the human triceps surae and its consequence on individual force-sharing strategies. Journal of Experimental Biology, 221(21).
  15. DiNaso, J. (2003). The Relationship Between Thigh Muscle Size and 1RM Squat Strength Among Bodybuilders, Powerlifters, and Olympic Weightlifters. Master’s thesis. Eastern Illinois University.
  16. Enoka, R. M., & Duchateau, J. (2017). Rate coding and the control of muscle force. Cold Spring Harbor Perspectives in Medicine, 7(10), a029702.
  17. Erskine, R. M., Fletcher, G., & Folland, J. P. (2014). The contribution of muscle hypertrophy to strength changes following resistance training. European Journal of Applied Physiology, 114(6), 1239-1249.
  18. Ertman, H., Szepietowski, O., Chiou, S. Y., & Strutton, P. H. (2016). Voluntary activation of abdominal muscles assessed using transcranial magnetic stimulation. Orthopaedic Proceedings, 98(6). The British Editorial Society of Bone & Joint Surgery.
  19. Evangelidis, P. E., Massey, G. J., Pain, M. T., & Folland, J. P. (2016). Strength and size relationships of the quadriceps and hamstrings with special reference to reciprocal muscle balance. European Journal of Applied Physiology, 116(3), 593-600.
  20. Fisher, B. E., Southam, A. C., Kuo, Y. L., Lee, Y. Y., & Powers, C. M. (2016). Evidence of altered corticomotor excitability following targeted activation of gluteus maximus training in healthy individuals. Neuroreport, 27(6), 415-421.
  21. Kingma, I., Aalbersberg, S., & van Dieën, J. H. (2004). Are hamstrings activated to counteract shear forces during isometric knee extension efforts in healthy subjects? Journal of Electromyography and Kinesiology, 14(3), 307-315.
  22. Loenneke, J. P., Buckner, S. L., Dankel, S. J., & Abe, T. (2019). Exercise-induced changes in muscle size do not contribute to exercise-induced changes in muscle strength. Sports Medicine, 49(7), 987-991.
  23. Mangine, G. T., Hoffman, J. R., Gonzalez, A. M., Townsend, J. R., Wells, A. J., Jajtner, A. R., … & Stout, J. R. (2015). The effect of training volume and intensity on improvements in muscular strength and size in resistance‐trained men. Physiological Reports, 3(8), e12472.
  24. McCurdy, K., Langford, G. A., Cline, A. L., Doscher, M., & Hoff, R. (2004). The reliability of 1-and 3RM tests of unilateral strength in trained and untrained men and women. Journal of Sports Science & Medicine, 3(3), 190.
  25. Schmidt, R. A., & Wrisberg, C. A. (2008). Motor learning and performance: A situation-based learning approach. Human Kinetics. Champaign, IL.
  26. Schoenfeld, B. J., Contreras, B., Vigotsky, A. D., & Peterson, M. (2016). Differential effects of heavy versus moderate loads on measures of strength and hypertrophy in resistance-trained men. Journal of Sports Science & Medicine, 15(4), 715.
  27. Taber, C. B., Vigotsky, A., Nuckols, G., & Haun, C. T. (2019). Exercise-induced myofibrillar hypertrophy is a contributory cause of gains in muscle strength. Sports Medicine, 49(7), 993-997.
  28. Vila-Chã, C., Falla, D., & Farina, D. (2010). Motor unit behavior during submaximal contractions following six weeks of either endurance or strength training. Journal of Applied Physiology, 109(5), 1455-1466.
  29. Willoughby, D. S., Stout, J. R., & Wilborn, C. D. (2007). Effects of resistance training and protein plus amino acid supplementation on muscle anabolism, mass, and strength. Amino Acids, 32(4), 467-477.

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