Category Archives: Brad Schoenfeld
You hit the gym on a regular basis and you train hard – really hard – but for some reason you’re just not making the gains that you should. All that sweat and effort, and without much to show for it.
If this sounds familiar, chances are you’re making at least one of the four critical mistakes outlined below. The good news is, with just a few simple tweaks to your program you can once again be packing on some serious muscle. Here’s how.
Mistake #1: You’re not varying your rep range.
The optimal number of repetitions for hypertrophy-oriented training is a source of ongoing debate in the fitness field. Although the research is by no means conclusive, evidence indicates that a moderate rep range (approximately 6-12 reps per set) is generally best for maximizing muscle growth.(1)
This is often referred to as “bodybuilding-style training” as it seems to provide the ideal combination of mechanical tension, muscle damage, and metabolic stress – the three primary factors involved in hypertrophic gains.(2) The problem is, most lifters seem to think this means all training should be carried out in this rep range and thus they rigidly adhere to the same loading patterns. Wrong assumption.
Understand that maximal muscular development is built on a foundation of strength. This mandates that at least some of your sets need to be carried out in the lower rep ranges (1-5 reps per set).
Stronger muscles allow you to use heavier weights, and thus generate greater muscular tension in the moderate repetition ranges that optimally stimulate hypertrophy. By increasing muscle tension without compromising metabolic stress, you’re setting the stage for enhanced growth.
On the other end of the spectrum, high rep sets (in the range of 15 to 20 reps per set) also have a place in a hypertrophy-oriented routine. Provided that training is carried out at or near your sub-rep max, lower intensity sets help to increase your lactate threshold, the point at which lactic acid rapidly begins to accumulate in working muscles.
The problem with lactic acid is that beyond a certain point its accumulation interferes with muscle contraction, reducing the number of reps you can perform.(3) (Technical note: it’s actually the H+ component of lactic acid that hastens the onset of muscular fatigue.)
Here’s the good news: Higher rep training increases capillary density and improves muscle buffering capacity, both of which help to delay lactic buildup. The upshot is, you’re able to maintain a greater time under tension at a given hypertrophy-oriented workload. In addition, you develop a greater tolerance for higher volumes of work–an important component for maximizing hypertrophy (see Mistake #2).
Take home message: Optimal muscle development is achieved by varying your rep range over time. This is best carried out in a structured, periodized program. Both undulating and linear periodized approaches can work, depending on your goals. Whatever scheme you employ, though, make sure you include the full spectrum of loading ranges.
Sure, hypertrophy training is probably best achieved with moderate rep sets, but higher and lower intensities are nevertheless important for optimizing muscular development.
Mistake #2: You’re not using sufficient volume.
Back in the 1970’s, Arthur Jones popularized the so-called high-intensity training (HIT) approach to building muscle. HIT is based on the premise that only a single set of an exercise is necessary to stimulate growth, provided you train to the point of momentary concentric muscular failure.
According to HIT dogma, performing additional sets beyond this first set is superfluous and perhaps even counterproductive to muscle development. Other prominent industry leaders such as Mike Mentzer and Ellington Darden subsequently followed Jones’s lead and embraced the HIT philosophy, resulting in a surge in its popularity. To this day, HIT continues to enjoy an ardent following.
Now before I get accused of being anti-HIT, I’ll readily admit that it’s a viable training strategy. There’s no denying that it can help build appreciable muscle. And if you’re time-pressed, it can provide an efficient and effective workout. That said, if your goal is to maximize muscle development, HIT simply doesn’t do the trick. You need a higher training volume. Substantially higher.
The prevailing body of research consistently shows that multiple set protocols are superior to single set protocols for increasing strength and size. Recent meta-analyses published in The Journal of Strength and Conditioning Research show that multiple set training results in 46% greater increases in strength and 40% greater increases in muscle growth when compared to single-set protocols.(4, 5)
Whether the hypertrophic superiority of multiple sets is due to greater total muscle tension, muscle damage, metabolic stress, or some combination of these factors isn’t clear. What’s readily apparent is that multiple sets are a must if you want to maximize your muscular potential. Problem is, even if you employ multiple sets it’s very possible you’re still not training with sufficient volume.
The optimal number of sets needed to elicit superior growth will vary from person to person and depend on a host of individual factors such as genetics, recuperative ability, training experience, and nutritional status.
But individual response is only part of the equation. The size of a given muscle also has relevance. Larger muscle groups such as the back and thighs need a higher volume than the smaller muscles of the arms and calves (which, by the way, also get significant ancillary work during multi-joint exercises).
Another important consideration here is the structure of your program. All things being equal, training with a split routine allows for a greater daily training volume per muscle group versus a total body routine.
And if you do indeed follow a training split, the composition of your split will influence training daily volume (i.e., a 3-day split allows for a greater volume per muscle group compared with a 2-day split). Accordingly, training volume is best determined on a weekly basis as opposed to a single session.
Whatever your target weekly volume, optimal results are achieved by taking a periodized approach where the number of sets are strategically manipulated over the course of a training cycle. Understand that repeatedly training with high volumes will inevitably lead to overtraining.
In fact, evidence shows that volume has an even greater correlation with overtraining than intensity.(6) Only by embracing periodization can you reap the benefits of a high training volume while avoiding the dreaded overtrained state.
Here’s a periodized strategy that I’ve found to be highly effective. Let’s say you’ve determined that your maximum weekly volume should entail performing 18-20 sets per muscle group. Focus on a three-month mesocycle where you target 8-10 sets a week the first month, 14-16 sets the second month, and then culminate with an overreaching cycle in the final month where you perform 18-20 sets per week.
Follow this with a brief period of unloading or active recovery to facilitate restoration and rejuvenation. Given that it generally takes one to two weeks for the full effects of supercompensation to manifest after completion of an overreaching cycle, you should realize optimal muscular gains sometime during the restorative period.
Mistake #3: You’re not adhering to the principle of specificity.
Most lifters don’t just want to get big, they also want to get leaner in the process. During the initial stages of training, this is a viable goal. Beginners can pack on serious muscle while simultaneously losing body fat without much of a problem.
The same applies for those with significant weight to lose (more than 30 pounds or so), as well as regular lifters who’ve taken an extended break from the gym. And yes, pharmacologic enhancement also will enable you to get huge and shredded in a hurry.
But if you’ve been training for more than a year or so, are fairly lean, and not “anabolically enhanced,” the quest to gain muscle while shedding fat becomes exceedingly difficult. At a certain point, you ultimately need to choose between one or the other.
If your choice is to bulk up, then this needs to be your training focus; otherwise results will be compromised. And this entails reevaluating how much aerobic exercise you perform.
The issue with concurrent training (i.e., combining resistance exercise and aerobics) is that it can interfere with the processes that drive anabolism. This is consistent with the AMPK-PKB switch hypothesis, which postulates that endurance and strength-related exercise activate and suppress distinct genes and signaling pathways, and these pathways have conflicting actions.(7)
Specifically, aerobic exercise regulates AMPK (adenosine monophosphate kinase), which is associated with pathways involved in carbohydrate and fatty acid metabolism. This of course has beneficial effects on fat loss.
Problem is, AMPK also inhibits activation of PKB-mTOR (mammalian target of rapamycin), an anabolic pathway that’s critical to protein synthesis and thus muscle building.
Now this doesn’t necessarily mean you should refrain from performing any cardio. While evidence supports the concept of an AMPK-PKB switch, recent research shows that it’s overly simplistic. Instead of a “switch,” adaptations between aerobic endurance exercise and resistance training appear to take place along a continuum, whereby substantial overlap exists between pathways.(8)
So while frequent, lengthy cardio sessions are bound to compromise muscle development, a more moderate aerobic routine likely won’t. And if nothing else, cardio is certainly good for your health and well being.
How much cardio is too much? Impossible to say. As with all aspects of exercise, individual response will vary based upon numerous genetic and lifestyle factors. Remember, too, that everyone has an upper limit to how much exercise they can tolerate before overtraining sets in.
Add in a cardio component to your routine and you increase the total amount of exercise-related stress placed on your body. At some point, these stresses can interfere with your recuperative abilities and bring about an overtrained state.
So for those looking to maximize muscle growth, the best advice is to err on the side of caution and limit the frequency, intensity, and duration of your aerobic sessions. Three days a week of 20-30 minute bouts is probably a good general guideline, but again this will vary from person to person. Monitor your progress, stay in tune with any signs of overtraining, and tweak your program as needed.
Mistake #4: You’re not taking in enough calories.
This mistake goes hand in hand with Mistake #3. In an attempt to get shredded while packing on mass, lifters will frequently restrict caloric intake while continuing to lift hard and heavy. Bad idea.
As previously noted, losing fat while gaining muscle is improbable for well-trained, natural lifters. If you fall into this category, it’s imperative that you consume a surplus of calories in order to support muscle growth.
This is consistent with the first law of thermodynamics, which states that energy can neither be created nor destroyed; only changed from one form to another. Simply stated, take in more calories than you expend and the excess energy will be stored in the form of body mass.
All-too-often lifters will take this to mean that it’s okay to eat everything in sight. This is consistent with the old-school “bulking” and “cutting” cycles where bodybuilders would scarf down massive quantities of food to get as big as possible and then go on an extreme diet with calories cut to starvation levels.
The problem with this approach is that upwards of 75% of weight gained during the bulking phase is in the form of body fat. Sure, you do gain muscle, too, but much of that is catabolized during the subsequent dieting process.
When all’s said and done, you’re lucky to retain half of your muscular gains. Worse, repeated cycles of bulking and cutting can reset your biological “set point,” leading to higher body fat levels in future cycles.(9) Bottom line, it’s simply not a smart nutritional strategy.
So what is an ideal caloric consumption for building muscle without porking up like a Sumo wrestler? A general guideline is to consume between 18 to 20 calories per pound of body weight. If you’re a 200-pound guy, this equates to a target caloric intake of about 3600 to 4000 calories a day.
Those who are endomorphs typically do better with slightly lower calories, while those who are ectomorphic usually need a higher energy intake; as much as 25 calories per pound for extreme hard-gainers.
Once you settle on a given caloric intake, monitor results over time and adjust consumption according to your individual response. If you’ve been lifting for a while, a realistic goal is to gain 1-2 pounds per month when focusing on mass-building.
If your muscular development has stagnated, it’s likely you’re making one of the aforementioned mistakes – perhaps you’re even a multiple offender. Fortunately, you’re not doomed to remain in a training rut. Identify the errors of your ways and then employ the solutions discussed above; you’ll soon be back on track to getting the most out of your muscular potential.
The most heated argument in strength and conditioning today is to crunch or not to crunch. It’s bewildering that this seemingly harmless, short ROM exercise could create such a rift between so many smart strength and conditioning professionals, yet the great crunch debate rages on.
At the center is research showing that repeated spinal flexion using cadaveric porcine spines resulted in herniated discs. This in vitro research seems to indicate that lumbar flexion is a potent herniating mechanism, and anti-crunch proponents have extrapolated from the data that humans possess a limited number of flexion cycles throughout their lifetimes.
Accordingly, they’ve gone out on a limb and recommended that spinal flexion exercises such as the crunch be avoided at all costs. While this may seem logical on the surface, there’s more to this topic than meets the eye.
Someone needs to step up and grow some balls and address the 2000-pound gorilla soiling the carpet. We know dozens of respected strength coaches, physical therapists, personal trainers, researchers, and professors that all have serious doubts about the danger of crunches, yet none wish to discuss it out of fear of being chastised.
The line must be drawn here!
Fitness is Religion
Humans have a basic need to fall into camps, rally behind a leader, believe in supernatural phenomena, and rebel against scientific principles. Throughout history scientists have been punished for questioning current dogma. Sadly, it’s no different in the fitness industry.
Many fitness professionals have been seeking a culprit for low back pain and jumped aboard the anti-crunch bandwagon without question. These folks have adopted absurdly rigid views of the lumbar spine, believing that you should go through life moving this region as little as possible to spare insult to the spine, to the point of altering normal biomechanics in daily living.
Taking it a step further, they then intimidate others into jumping on the bandwagon and get downright emotional when confronted on the topic.
This is the antithesis of scientific thinking. We’re just happy that we won’t be house-imprisoned like Galileo for hypothesizing that the Earth wasn’t the center of the universe.
After delving into the topic, reviewing the literature, and applying our critical thinking skills, we’ve concluded that like every other exercise, a reasonable dose of spinal flexion exercise is potentially good for you and need not be avoided.
We presented our position in a review paper published in the Strength & Conditioning Journal and while we won’t rehash everything in the article, we do continue to question the recent “anti-crunch” movement and suggest a plausible alternative theory.
In our journal article we addressed the following issues, which will only be succinctly summarized below.
For more detailed explanations and citations, we encourage you to pull up the article and read it in its entirety.
Methodological Issues in Research Against Lumbar Flexion Exercise
Removal of muscle. The experiments used in the studies used to refute lumbar flexion exercise used porcine (pig) cervical spines with muscles removed, which alters spinal biomechanics.
No fluid flow in cadavers. Cadaveric spines don’t function the same as living spines as fluid doesn’t flow back into the discs as it does when tissue is alive.
Range of motion in porcine spine. Porcine cervical spines have smaller flexion and extension ranges of motion than human lumbar spines.
Doesn’t mimic crunch exercise regimen. When most people do crunches, they might do a few sets of 10 to 20 reps or so and then wait a couple of days before repeating. This allows the discs to repair and remodel. In the studies used to bash lumbar flexion, thousands of nonstop cycles were performed, which does not replicate a strength and conditioning regimen. It should also be noted that cadaveric spines do not remodel while living spines do.
Genetics. In the world of intervertebral disc degeneration, the role of genetics is huge. It appears that some individuals are quite prone to disc issues while others are not, suggesting that optimal programming would require knowledge of genetic traits.
Range of motion in the crunch exercise. Many years ago, an NSCA journal article described proper performance of the crunch exercise, which involved 30 degrees of total trunk flexion, most of this motion occurring in the thoracic spine, not the lumbar spine. If the lumbar spine doesn’t approach end range flexion in the crunch exercise, then the studies wouldn’t be applicable to the crunch exercise.
IAP controversy. There’s a chance that models used to estimate compressive forces during the crunch have been overestimated due to failure to take into account the role of intra-abdominal pressure (IAP). If this is the case, then the studies could have used too much compression along with range of motion mentioned earlier, which would render the studies inapplicable to crunching. However, there’s conflicting research in this area and it’s likely that the effect isn’t significant.
Potential Benefits of Lumbar Flexion Exercise
Increased fluid flow and nutrition to posterior disc. Lumbar flexion enhances nutrient delivery to discs by increasing nutrient-carrying fluids to the discs.
Increased remodeling of tissue. Proper doses of spinal flexion likely strengthens the disc tissues, which would therefore increase tolerance to lumbar flexion exercise and prevent future injury.
Sagittal plane mobility. Some studies have linked lack of spinal mobility to low back pain, however the literature is somewhat contradictory. At the very least crunches can prevent losses in spinal mobility, which might be important in low back pain prevention.
Rectus abdominis hypertrophy. When taking into account the entire body of knowledge on hypertrophy research, it’s abundantly clear that dynamic exercise is superior to isometric exercise in increasing muscle mass. Much of this has to do with the increased muscular damage incurred from eccentric activity as well as the increased metabolic stress. Bottom line, if you want to optimize your “six-pack” appearance, spinal flexion exercises will certainly help to achieve this goal.
Performance enhancement. Contrary to what some have claimed, lumbar flexion is prevalent in many sport activities. Thus, concentrically/eccentrically strengthening the abdominals may very well lead to increased athletic performance.
Anecdotes and Other Arguments
Now let’s look at some anecdotal evidence to support our claims.
If we’re indeed “limited” in the number of flexion cycles, where does the number lie?
Several fitness professionals have suggested that humans possess a limited number of flexion cycles and believe that we should save these cycles for everyday living such as tying one’s shoe rather than wasting them on crunches. Realizing that anecdotal evidence doesn’t prove squat, it’s still interesting to ponder and can provide a basis for theoretical rationale.
- In 2003, Edmar Freitas, a Brazilian fitness instructor, performed 133,986 crunches in 30 hours, thereby setting a world record. This beat his previous record of 111,000 sit-ups in 24 hours set in the prior year.
Manny Pacquiao, one of the world’s best boxers, performs 4,000 sit-ups per day.
- Finally, Herschel Walker, football legend, Olympic bobsledder, and current MMA hopeful, has been performing 3,500 sit-ups every day since he was in high school. He started doing sit-ups daily when he was 12 years old. Considering that he’s now 49 years of age, this equates to 47,267,500 sit-ups. That’s almost 50 million flexion cycles performed under compressive loading!
Granted, the argument could be made that perhaps all these individuals have screwed up spines and if you were to obtain MRI’s from each you’d see appalling evidence of herniations and degeneration, but we doubt this is the case. Instead we believe that this is clear evidence that the spinal discs can remodel and become stronger over time to resist damage incurred from spinal flexion exercise.
Another argument could be made that these folks are “outliers” and their freakish genetics allow for such incredible flexion cycles. We disagree, and believe there are likely many individuals that have unknowingly met or exceeded this number in their lifetimes. Instead, we believe that this is evidence that muscular balance, abdominal strength, and flexion exercise can protect the spine.
Should We Just Shoot Ourselves?
If we cherry-picked select disc studies to determine which forms of exercise we do, we wouldn’t be allowed to do literally anything.
We found 13 studies to indicate that spinal flexion is a bad idea. (Callaghan and McGill, 2001; Drake et al., 2005; Tampier et al., 2007; Drake and Callaghan, 2009; Marshall and McGill, 2010; Adams and Hutton, 1982; Adams and Hutton, 1983; Adams and Hutton, 1985; Lindblom 1957; Brown et al. 1957; Hardy 1958; Veres et al., 2009; Court et al. 2001). This means no crunches and sit ups.
We found 11 studies that showed that combinations of spinal loading aren’t a good idea. (Gordon et al. 1991 (Flexion and Rotation); McNally et al. 1993 (Flexion and Anterolateral Bending); Shirazi 1989 (Lateral Bending and Rotation); Kelsey et al. 1984 (Flexion and Rotation); Adams et al. 2000 (Complex); Marshall and McGill, 2010 (Flexion/Extension and Rotation); Drake et al. 2005 (Flexion and Rotation); Veres et al., 2010 (Flexion and Rotation); Schmidt et al. 2007 (Lateral Bending and Rotation, Lateral Bending and Flexion, Lateral Bending and Extension); Schmidt et al. 2007 (Lateral Bending and Flexion, Lateral Bending and Rotation, Flexion and Rotation); Schmidt et al. 2009 (Lateral Bending and Flexion, Lateral Bending and Extension). This means no exercises such as twisting sit-ups or Russian twists.
We found a couple studies showing that spinal extension is a big no-no (Adams et al., 2000; Shah et al., 1978). This means no Supermans.
Several studies show that spinal rotation is bad (Krismer et al., 1996; Aultman et al. 2004; Farfan et al. 1970). This means no cable chopping motions. And you better not be performing these on a vibration platform as that would produce a double whammy to the spine. Vibration has been shown to be bad for the discs (Dupuis and Zerlett 1987).
There’s research to suggest that lateral bending is bad for you (Costi et al. 2007; Natarajan et al. 2008). This means no side bending. Similarly, asymmetrical lifting has been shown to lead to negative results as well (Natarajan et al. 2008). This means no unilateral exercises or weighted carries.
Here’s where things get interesting. We found 18 different studies showing that static or dynamic compression is a very bad idea (Virgin 1951; Liu et al. 1983; Lai et al. 2008; Lotz et al. 1998; Tsai et al. 1998; Iatridis et al. 1999; Lotz et al. 1998; Kroeber et al. 2002; MacLean et al. 2003; Hsieh and Lotz 2003; MacLean et al. 2004; Ching et al. 2004; Masouka et al. 2007; Veres et al. 2008; Lai and Chow 2010; Nakamura et al. 2009; Wang et al. 2007; Huang and Gu 2008).
This not only means no squats, deadlifts, and core stability exercises, it means no physical activity involving free weight exercise whatsoever, since muscular contractions create compressive loading on the spine. We should have known that though, as heavy lifting is bad for the back (Lee and Chiou 1994; Kelsey et al. 1984), as is overactivity (Videman and Battie, 1999). So now we know that weightlifting and intense training is out.
It goes on and on. We’ve found studies suggesting all sorts of every day activities are bad for the back, even sitting down and bed-rest. Maybe we should all just shoot ourselves before we become completely debilitated?
Do Crunches Screw up Your Posture?
The theory goes something like this: Crunches shorten the rectus abdominis. Since the rectus abdominis spans from the sternum/rib cage to the pelvis, continually shortening the muscle will pull down your ribcage, ultimately resulting in kyphosis (i.e. a round-back posture). It’s an interesting theory. It’s also completely unfounded.
As with many theories, the essence of this claim is based on a kernel of truth. Specifically, placing a muscle in a shortened position for a prolonged time causes it to assume a shorter resting length. For example, if you immobilize your arm in a cast at a flexed position for several weeks, your arm will tend to remain flexed once the cast is removed.
This is due to an adaptive response whereby the elbow flexors (i.e. biceps, brachialis, etc.) lose sarcomeres in series while sarcomeres are added to the antagonistic extensor muscles (Toigo & Boutellier, 2006). This has been coined “adaptive shortening.”
Perhaps you can see the flaw in hypothesizing that performing a crunch will shorten the rectus abdominis, namely, crunches aren’t solely a shortening exercise! Rather, the crunch also includes eccentric actions where the rectus abdominis is returned to its resting length.
Thus, any potential negative effects of shortening contractions on sarcomere number would be counterbalanced by the lengthening effect of the eccentric actions. The net effect is no change in resting length.
Some anti-crunch proponents also argue that performing spinal flexion exercises (i.e. crunches) overly strengthens the rectus abdominis so that it overpowers its antagonists, thereby pulling down on the ribcage.
This is a straw man argument. Certainly it’s true that an imbalance between muscles can cause postural disturbances – I’m sure you’re familiar with guys who hit chest and arms every workout and end up so internally rotated that they have trouble scratching the back of their head. But this doesn’t mean you shouldn’t perform bench presses and arm curls.
The issue here is one of poor program design, not an indictment of specific exercises.
Regarding crunches, the same principle holds true. Sure, if you perform a gazillion crunches every day and don’t train other muscle groups, you’re setting yourself up for a postural disturbance.
But this is a non-issue if you adhere to a balanced routine. Performance of virtually any standing, non-machine based exercise will heavily involve the core musculature, particularly the posterior muscles that antagonize the rectus abdominis (Schoenfeld, 2010, Lehman, 2005). It also should be noted that the average person tends to have weak abdominals (Morris et al. 2006), so they could very well benefit from performing spinal flexion exercises.
To sum up, there is no convincing evidence that performing crunches as part of a total body resistance training routine will have any negative effects on posture.
Do crunches lead to additional dysfunction, such as breathing dysfunction and glute dysfunction?
If crunches did indeed pull down on the ribcage and induce kyphosis, then one could speculate that breathing and glute functioning could be compromised. However, as just mentioned, this likely isn’t the case.
Anecdotally, hundreds of thousands of athletes in the past few decades have achieved terrific success in spite of doing crunches. If crunches did lead to shortening of the abdominals, given that a majority of people including athletes seem to display an anterior pelvic tilt in their daily posture, one could argue that it would be wise to perform crunches to pull up on the pelvis, which could theoretically decrease anterior pelvic tilt and lead to a more neutral lumbo-pelvic posture.
Are crunches a nonfunctional exercise?
Whenever one questions the implication that crunches are as dangerous as wake boarding in a tsunami, anti-crunchers quickly counter with something like, “Who cares if they’re dangerous or not? Crunches aren’t functional! They’re a short range movement performed while lying on your back. They can’t possibly transfer to anything.”
As our mentor Mel Siff aptly stated:
Anti-crunchers will point out that the crunch solely involves bodyweight and therefore isn’t heavy enough to transfer to high-force or high-velocity movement. This is absurd, as it’s very easy to hold a dumbbell at the upper chest to increase the exercise’s intensity. You also can perform a kneeling rope crunch using a cable apparatus to increase training intensity.
What carries over best to functional activity depends on the task. Here’s a chart that should help you determine optimal transfer of training.
|Biomotor Ability||Examples||Exercise Category||Examples|
|Trunk Rotary Stability, Strength and Power||Throwing a football or baseball, throwing a discuss, swinging a bat, throwing a left hook||Rotational exercises and anti-rotation exercises||Woodchops, landmines, Pallof presses, cable or band chops and lifts|
|Trunk Lateral Bending Stability, Strength and Power||Stiff-arming, posting up, landing a jab||Lateral flexion exercises and anti-lateral flexion exercises||Side bends, side planks, suitcase carries, cable or band side bends|
|Trunk Flexion Stability, Strength and Power||Sitting up from a bench, bar gymnastics exercises, bracing for a punch to the midsection, resisting being pushed rearward as in sumo wrestling, throwing a soccer ball overhead||Flexion exercises and anti-extension exercises||Crunches, sit ups, hanging leg raises, planks, ab wheel rollouts, bodysaws|
|Trunk Extension Stability, Strength and Power||Carrying heavy loads, picking up stuff off the ground, staying upright in the clinch||Extension exercises and anti-flexion exercises||Squats, deadlifts, back extensions, reverse hypers, farmer’s walks, Zercher carries|
Basically, stability exercises appear to be better for stabilization tasks as well as tasks that require proper inner-core unit functioning, while strengthening exercises appear to be better for dynamic tasks and hypertrophy.
As you can see, an exercise like a weighted crunch could transfer quite well to a myriad of functional tasks, and therefore shouldn’t be maligned for its applicability to functional or sports performance.
Is There a Healthy Balance and Do Discs Heal and Remodel?
It’s been stated by many practitioners that the discs don’t heal. This is misleading. It’s true that they’re poorly vascularized and struggle to receive adequate nutrition, and it’s true that disc tissue doesn’t heal rapidly. Proteoglycan turnover may take 500 days (Urban et al. 1978) and collagen turnover may take longer (Adams and Hutton 1982).
Hence, the discs’ rate of remodeling lags behind that of other skeletal tissues (Maroudas et al. 1975; Skrzypiec et al. 2007).
However, much evidence of disc-healing exists. Common sense would dictate that discs do heal, otherwise anyone that suffered a disc injury would never get better. We’d all just get progressively worse until we could no longer move.
Based on epidemiological studies, it’s clear that there’s an optimal window of spinal loading that is somewhere in between bed-rest and overactivity (Videman et al., 1990).
A healthy balance has been shown to occur with spinal compression (Hutton et al. 1998; Lotz et al. 2002; Walsh and Lotz 2004; Wuertz et al. 2009; MacLean et al. 2005) and spinal rotation (Chan et al. 2011). Positive aspects of spinal bending have been shown to occur in the discs as well (Lotz et al. 2008; Court et al. 2001).
Furthermore, 16 different studies indicate that the spinal discs can repair and remodel themselves. While several papers reviewed the topic (Lotz 2004; Stokes and Iatridis; Adams and Dolan 1997; Porter 1987), others demonstrated that flexion damages can heal (Court et al. 2007), compression damages can heal (Lai et al. 2008; Korecki et al. 2008; MacLean et al. 2008; Hee et al. 2011), prolapses can reverse (Scannell and McGill 2009), herniations can improve (Girard et al. 2004; Wood et al. 1997), the outer annulus can strengthen (Skrzpiec et al. 2007), collagen within the disc can remodel to become stronger (Brickley-Parsons and Glimcher, 1984), and vertebrae, ligaments, and strengthen to resist loading (Porter et al. 1989; Adams and Dolan 1996).
Every time you move your spine you cause micro-damage to the tissues, which triggers both anabolic and catabolic processes. Ideally, you want to limit the amount of damage, as healing from larger scale damage usually leaves the disc biomechanically inferior.
For example, annular damage is repaired by granulation tissue and the scar never regains its normal lamellar architecture (Hampton et al. 1989). End plate injuries heal with cartilaginous tissue (Cinotti et al. 2005; Holm et al. 2004), fibrocartilage replaces nucleus material (Kim et al. 2005), and a healing of harmed tissue is often replaced by a thin-layer of weaker fibrous tissue (Fazzalari et al. 2001).
A Stress – Eustress Solution?
The study of biomechanics is unique because you must not only consider forces and stresses on human tissues, you must also consider adaptive remodeling. The ideal situation in programming doesn’t avoid stress; it keeps the body in eustress while avoiding distress, which ensures that anabolic agents inside of tissues exert more work than catabolic agents inside of tissues to promote full repair, recovery, and strengthening.
We hope that we’ve provided you some food for thought and encouraged you to rely on logic rather than emotion in decision-making involving exercise safety and program design. An effective practitioner weighs all available evidence and makes appropriate conclusions in a dispassionate manner, without adhering to rigidly held beliefs.
We believe that future research will help hone in on the safety of the crunch exercise and determine proper dose responses, but this research needs to be conducted on living humans and involve pre and post-MRI results with a training intervention that ensures proper crunch technique.