by Bret Contreras
They both lifts weights. They both train hard. They both use drugs at the pro levels. So why are bodybuilders more jacked than powerlifters?
The Powerlifter Look
We all know that there are some freaky-looking powerlifters. That said, generally, powerlifters aren’t as muscular as bodybuilders. Name your favorite jacked powerlifter and we’ll show you a bodybuilder who dwarfs him in terms of muscularity.
Granted, many powerlifters carry too much body fat to accurately assess their level of muscularity. For example, here are pictures of Donnie Thompson, Ryan Kennelly, and Benedikt Magnusson. In 2011, these guys were the owners of the world’s strongest squat and powerlifting total, strongest bench press, and strongest deadlift, respectively.
Clearly these guys are beasts, but they’re definitely not the most muscular guys on the planet. But if they dropped down to reasonable body fat levels they’d likely lose a lot of muscle in the process.
One of the most muscular powerlifters who consistently displays excellent conditioning is Konstantin Konstantinovs.
He’s certainly a freak, but put him next to Ronnie Coleman in his prime and suddenly his muscularity isn’t as impressive.
In late 2010, Stan Efferding won the World’s Strongest Bodybuilder competition. Stan owned the highest raw powerlifting total in the world, but he’s not the most muscular bodybuilder.
Fact is, if you examine pictures of Stan and other powerlifting bodybuilders like Johnnie Jackson and Ben White, you’ll notice that all three of these athletes possess mediocre lower body development by bodybuilding standards.
In 1993, Tom Platz, owner of perhaps the biggest wheels in bodybuilding history, entered into a squatting competition with Fred Hatfield, the first guy to squat 1,000 pounds.
Although Tom’s legs were much bigger than Fred’s, Fred kicked his butt in a one-rep max, hoisting 855 pounds to Tom’s 765 pounds. But when they took some plates off the bar and decreased the weight to 525 pounds for a test of lower-body endurance, Tom dusted Fred, performing 23 reps compared to Fred’s 11.
Bottom line is, bodybuilders seem better at high reps with a smooth cadence, whereas powerlifters seem more adept at low reps performed explosively.
Former Mr. Olympia Jay Cutler has written some very honest and forthright commentary on strength and muscular size. He listed his all-time best lifts along with his current strength.
He used to train with much heavier weights several years back, but he got more muscular by using “lighter” weights. While he still trained heavy, he chose to focus more on quality than quantity.
Muscular Differences in Bodybuilders and Powerlifters
Many lifters, trainers, and coaches believe that “muscles only know tension.” This view is overly simplistic. In reality, a number of factors must be taken into account.
What degree of tension? What duration of tension? What frequency of tension? What kind of tension? Certainly, passive tension isn’t as effective as active tension in packing on lean mass.
Many believe that the continuous quest for increased maximal strength is the key to developing massive muscles. But while increased strength is related to increased muscle cross-sectional area (CSA), there are multiple adaptations that can boost strength without increasing muscle hypertrophy.
Of these adaptations, basic coordination between the muscles is the single greatest contributor to non-hypertrophy-related strength gains.
Along with neurological adaptations, adaptations involving increased stiffness in the tissues that connect from bone to bone (including tendons, extracellular matrix, etc.) can lead to increased force transmission from muscle to bone, and play a significant role in increased strength gains.
Pennation Angle
The angle formed by the individual muscle fibers with a muscle’s line of action significantly impacts strength irrespective of muscle hypertrophy.
Specifically, increased pennation angles appear to have a negative correlation with muscle strength - as pennation angle increases, a muscle’s force-generating capacity decreases.
Interestingly, studies show that bodybuilders have greater pennation angles than powerlifters, potentially due to their training methods.
Types of Hypertrophy
There are multiple ways in which muscles can grow larger without significantly affecting maximal strength. One way this occurs is by an increase in non-contractile elements in the muscle cell.
Non-contractile hypertrophy includes increases in collagen, glycogen, and other cellular subunits, a phenomenon commonly referred to as “sarcoplasmic hypertrophy.”
Since force production is generated by the sarcomeres, sarcoplasmic hypertrophy will have no effect on your 1RM. However, the increased bulk provided by the non-contractile elements will nevertheless produce a tangible impact on muscle size.
Slow-Twitch Muscle Fiber Growth
An increase in the size of slow-twitch Type I fibers can also affect hypertrophy without having much effect on maximal muscular strength. Type I fibers are endurance-oriented fibers that have limited ability to produce high levels of force.
Type I fibers do increase in size when subjected to a resistance training stimulus, although their hypertrophic capacity is about 50% less than that of fast twitch fibers.
Bodybuilders have been shown to have a greater Type 1 cross-sectional area than powerlifters. This may help explain why Tom Platz displayed greater muscular endurance than Fred Hatfield but wasn’t as strong on an absolute basis.
If maximum strength were the end-all-be-all for muscular hypertrophy then powerlifters would be the biggest human beings on the planet, and bodybuilders would employ maximal singles instead of chasing the pump.
Simply put, stronger does not necessarily equal bigger, and bigger does not necessarily equal stronger.
What then, makes bodybuilders more muscular than powerlifters?
It’s Not Genetics
Sure, people naturally gravitate toward what they’re good at.
In the world of strength training, those with a greater predisposition for strength will be more inclined to train like or become a powerlifter, while those with a greater predisposition for size will be more inclined to train like or become bodybuilders.
Powerlifting has more to do with leverages, the nervous system, and technique refinement, while bodybuilding has more to do with aesthetics, symmetry, muscularity, and conditioning.
Strength is dependent on plenty of factors, but tendon insertions play a huge role in the ability to exert maximal force.
Let’s use a biceps curl as an example. Say you’re curling a 60-pound dumbbell and you’re halfway up at 90 degrees and moving very slowly.
To figure out a general estimate of muscle force requirements of the biceps, you divide the moment of the resistance arm by the length of the muscle arm.
This means that you multiply the resistance (60 pounds) by the resistance arm (say 15 inches from the elbow to the dumbbell) and then divide it by the muscle arm (say 1 inch from the elbow to the biceps insertion).
This would give us 900 inch-pounds, a measure of torque. In this example, the biceps must produce 900 inch-pounds of force.
What happens if the individual’s biceps tendon inserts 2 inches away from the fulcrum? Now you divide by 2 instead of 1, which means that the biceps now only has to produce 450 inch-pounds of force to hold a 60-pound dumbbell at a 90-degree elbow angle.
This demonstrates just how advantageous tendon insertions are to external force production - two guys could have equal strength in their biceps but one can lift twice the amount of weight due to his leverages.
Torso, arm, femur, and tibia lengths and proportions all play a large role in the display of strength as well. Obviously, the sample size of professional powerlifters and bodybuilders will be skewed. There’s also more money involved in bodybuilding.
Still, this doesn’t explain why bodybuilders are more muscular than powerlifters. And one glaring observation is important to consider - when powerlifters start training like bodybuilders, they nearly always gain more muscle!
It’s Not Chemical Assistance
Sure, pro bodybuilders take large amounts of performance-enhancing drugs, but so do powerlifters. Perhaps bodybuilders take higher doses and use a wider array of compounds, but many claim to use moderate doses and stick to the basics, so whether this indeed plays any role is unknown.
So let’s compare the physiques of natural bodybuilders with those of natural powerlifters. In this case, it’s no comparison at all. WNBF bodybuilders dwarf WNPF powerlifters from a hypertrophy standpoint.
Ten Reasons Bodybuilding Gets You Bigger
Bodybuilders are masters of packing on muscle. While everybody responds uniquely to various exercises, loads, volumes, frequencies, intensities, densities, and durations, there are certain rules that apply to bodybuilding.
If your goal were to maximize muscle development, you’d be a fool to ignore them. While mechanical tension appears to be paramount in hypertrophy stimulation, here are several possible candidates that could explain the superior musculature of bodybuilders over powerlifters.
1. Higher Reps and Chasing the Pump
Powerlifters generally train in a low rep range (1-5 reps) while bodybuilders tend to favor a moderate rep range (6-12). The adaptations associated with these may explain at least part of the hypertrophic differences between these two classes of athletes.
Performing higher reps would theoretically result in greater hypertrophy of Type 1 fibers. As previously noted, Type 1 fibers are endurance-oriented and thus respond best to longer times under tension.
The low-rep training employed by powerlifters simply doesn’t allow enough time under tension for significant development of these fibers.
The Pump Serves a Purpose
While the pump is often thought of as a short-term training effect, it can result in greater muscle development. Studies show that cellular swelling causes both an increase in protein synthesis and a decrease in protein breakdown.
It’s theorized that an increase in water within the muscle cell - consistent with the mechanisms associated with “the pump” - is perceived as a threat to its integrity. In response, the cell initiates a signaling cascade that ultimately causes the muscle to grow larger to protect the ultra-structure.
In addition, greater occlusion and hypoxia may be associated with higher rep pump-style training, which can induce growth through increases in growth factor production and possibly satellite cell fusion.
Chasing the pump with moderate rep ranges promotes sarcoplasmic hypertrophy - an increase in non-contractile elements. While this in itself manifests as increased muscle size, it may also promote additional increases in contractile hypertrophy.
Glycogen is hydrophilic (water-loving). Each gram of glycogen attracts three grams of water into the muscle cell. This increased hydration may thus lead to greater myofibrillar growth through cell swelling mechanisms, providing double-duty for increasing hypertrophic gains.
2. Time Under Tension
It’s also important to take into account the higher levels of poundage (weight x reps) and time under tension (TUT) performed by bodybuilders in comparison to powerlifters.
Let’s say a bodybuilder performs a bench press routine consisting of 225 x 12, 275 x 10, 315 x 8, and 335 x 6, while a powerlifter does 315 x 5, 365 x 3, 405 x 1, and 415 x 1. Under this scenario, the bodybuilder lifted 9,980 total pounds while the powerlifter lifted 3,490 total pounds.
Assuming 2 seconds per repetition, the bodybuilder accumulated 72 seconds under tension while the powerlifter accumulated 20 seconds under tension - a significant difference!
3. High Reps to Failure
High reps to failure are better than low reps to failure for myofibrillar, sarcoplasmic, and mixed protein synthesis.
Although interesting, more research is required as acute protein synthesis doesn’t necessarily correlate to greater hypertrophy over time and previous studies have found very high rep protocols to be suboptimal for increasing muscle growth.
More total reps also equate to more eccentric contractions, which have been shown to create more muscular damage. There’s a large body of evidence suggesting that muscular damage is associated with increased muscle growth, although research is still inconclusive in this area.
4. Muscle Isolation and Machines
Bodybuilders include many single-joint movements in their training. This is in direct contrast to powerlifters, who generally stick with a few basic multi-joint lifts.
Large muscles such as the quads, pecs, delts, and lats are made up of many thousands of threadlike fibers that have multiple different attachment sites. These fibers are sometimes compartmentalized or supplied by different nerves.
Thus, muscles don’t always get worked evenly throughout their entire length during exercises. A certain exercise may stress a region closer to the origin or closer to the insertion. Only by training from multiple angles with a variety of exercises can you fully stimulate all of these fibers, and thus maximize their development.
Employing some machine-based training, which reduces stabilizer involvement allowing targeting different aspects of a muscle, can further maximize muscle development.
Machines can be beneficial by creating favorable strength curves with cams and other technology that helps keep constant tension on the muscles. Constant tension can lead to greater mechanical signaling and a better pump, which can assist in muscular growth.
5. Manner of Execution
Bodybuilders have been saying for years that it’s not just about the amount or resistance used, it’s also about the manner of execution.
Bret’s EMG experiments found that a 225-pound bodybuilding-style bench press (wider grip, elbows flared, bar lowered to mid-chest) activated more pectoralis major fibers than a 225-pound powerlifting-style bench press (narrower grip, elbows slightly tucked, bar lowered to lower chest).
Often, maximum attempts at squats and deadlifts yielded lower EMG activation than submaximal lifts. This is due to the body instinctively contorting itself to lift heavier weights, and the contortions often involve invoking assistance from passive structures such as ligaments.
For example, a powerlifter might round his upper back excessively to “hang” on his ligamentous structure, which increases passive assistance while simultaneously decreasing active muscle requirements.
Professional bodybuilders typically control the weight and use a smooth tempo, whereas many powerlifters allow some form deterioration when approaching a max. Furthermore, many bodybuilders avoid the lockout position to keep constant tension on the targeted muscle.
For example, let’s say a bodybuilder is performing dumbbell incline presses. He might go 5/6ths of the way up and then reverse the weight and head back down. During a pec fly the bodybuilder may only go 2/3rds the way up. In this manner, the tension is kept on the pecs to facilitate a better pump.
6. Mind-Muscle Connection
Bodybuilders often preach about the feeling the muscle work. Research has shown that activation training can increase the relative EMG activity during an exercise.
For example, a two-month focus on glute activation could cause an individual to use more glute muscle during a compound exercise such as a squat or lunge, and possibly decrease the involvement of synergists such as the hamstrings.
Bodybuilders purposely target an intended muscle and manipulate their form to maximize the tension on that muscle.
On the other hand, all powerlifters care about is lifting maximal poundages. Thus, they try to involve as many muscles as possible to generate optimum force.
For example, during the bench press, a powerlifter attempts to maximize leg drive along with pec, lats, anterior delts, and triceps contribute to lift the heaviest weights possible. They’re more concerned with optimal mechanics than muscle activation.
While the powerlifting method is great for total body stimulation, the bodybuilding method really hammers a particular area and might induce more damage and a greater pump while reducing overload to the CNS.
7. Instinctive Training and Biofeedback
Bodybuilders incorporate a wide variety into their workouts and often don’t have a set plan when they enter the gym.
Many have a general idea about what they want to accomplish, but typically leave room for spontaneity based on biofeedback. This variety and loose-structure could theoretically lead to greater muscle growth over time due to a decreased likelihood of injury.
The lifter who can come to the gym week in, week out for many years and perform productively, pain-free workouts will accumulate more lean mass than the lifter who is always banged up, training through pain, and suffering from tears and ruptures.
Since absolute strength is paramount to a powerlifter, many times a powerlifter will ignore glaring biofeedback telling them to back off. For example, perhaps the low back feels dodgy on deadlift day. The powerlifter will usually stick to the plan and push through it, while the bodybuilder will work around it.
Since the bodybuilder thinks in terms of “working muscles” instead of building lifts, often he’ll listen to the body’s warning signals and find a movement that doesn’t set off red flags.
Powerlifters by nature are obsessed with maximal strength on the big three lifts, whereas most bodybuilders view strength as a means to build muscle and don’t really care how much they can squat, bench, or deadlift.
8. Intensification Methods
Occasionally, bodybuilders will employ intensification methods to take a set to the limit such as training to failure, negatives, drop sets, rest-pause, burnouts, supersets, tri-sets, and quad-sets.
When performed sparingly, these methods can deliver additional hypertrophy stimulating signals that can theoretically lead to greater muscle growth over time, though they should be periodized properly to avoid overtraining.
9. Shorter Intra-Set Rest Times
Bodybuilders generally take fairly short rest periods between sets - around a minute or two on average, whereas powerlifters often take up to five minutes of rest between heavy sets. Shorter rest intervals have been associated with an increased anabolic hormonal response, particularly testosterone and growth hormone.
Although it’s unclear whether the acute hormonal effects of resistance exercise contribute to greater muscle growth, several studies have reported a significant correlation with the magnitude of growth in both type I and type II muscle fibers.
At the very least, shorter rest times will increase training session density, increase “the pump,” and increase hormonal milieu. The improved anabolic milieu should facilitate an improved environment for increasing muscle protein synthesis and possibly satellite cell activity, though studies in this area are inconclusive.
10. Training Splits
Bodybuilders tend to arrange their training sessions around targeting one or two muscle groups with multiple sets of several different exercises. Bodybuilders will then wait several days, and often up to a week, to work that same muscle group.
Research shows that it takes up to seven days to fully recuperate from performing multiple sets of the same muscle group, and there’s evidence to show that exercising too often could result in decreased hypertrophy.
Clearly more research needs to be conducted when you consider that bodybuilders who are trying to improve the appearance of a particular body part and bring up a “weak point” usually increase training frequency up to 2-3 times per week with great success.
The Power Bodybuilder
Can we simultaneously train for both powerlifting and bodybuilding and thereby achieve a win/win situation? In other words, by incorporating a bit of both can you maximize strength and size?
The authors of this article believe that you can’t.
You see, signals to muscles are very specific, and by mixing signals you send conflicting messages that will affect the body’s response. Johnnie Jackson has achieved success as a powerlifter and a bodybuilder, but to maximize his leg development he trains like a bodybuilder.
Now in no way does this imply that you shouldn’t periodize your routine and incorporate periods of heavier weight and lower rep ranges - quite the opposite - it’s a highly beneficial strategy.
For example, suppose that you can deadlift 405 for 3 sets of 8 repetitions and your deadlift 1RM is 515. Let’s say you spend five weeks performing heavy sets of 3 reps or lower, and you raise your 1RM to 585.
Now you go back to performing 3 sets of 8 reps, but you find that you’re able to use 425 for 3 sets of 8. This will definitely assist with muscular hypertrophy as you’re generating more muscular tension within the same target rep range.
However, you should not obsess with powerlifting totals and try to blend too much powerlifting techniques into your hypertrophy training if increased muscularity is your primary goal.
It seems quite clear that if your goal is to maximize muscular development it’s important to never stray too far away from proven bodybuilding principles.
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