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Real Science vs. Broscience: Training

Part two in my two-part series on the battle between published science and commonly-held myths otherwise known as "broscience"

Real Science vs. Broscience: Training

As I explained in the first part of this two-part series, Real Science vs. Broscience: Supplements, I am dedicated to bringing the truth about training, supplementation, and nutrition to consumers. I'm also dedicated to putting info out there in a way that makes science less boring. 

There is a LOT of broscience going around the gym these days. By broscience, I mean common beliefs that go around gyms and among bodybuilding circles. An example of broscience would be that doing slow and steady cardio for 30-60 minutes (such as walking on a treadmill) is the best way to burn fat and keep muscle with cardio. Despite this belief—commonly held by many—published science (by that I mean the research that is published in peer-reviewed scientific journals or presented at scientific meetings) has shown that high-intensity interval training (HIIT) is the best form of cardio to burn fat and maintain (or even build) muscle, and the anecdotal reports support this.

That isn't to say that gym-goers are wrong 100% of the time. In fact, as you'll soon learn, sometimes results in the gym prove results from the lab wrong. In this article, I'll be pitting published science against broscience when it comes to training.

Is Pre-Exhaust Training Useless?

Not only is misinformation rampant among many so-called fitness "experts," but some training techniques are simply misunderstood. A prime example of this is pre-exhaust. This method was shown in a 1996 study to build more muscle than the standard training protocol where multi-joint exercises are performed first.

Despite this study, however, there are some out there—even among experts!—who doubt the usefulness of this technique.

Broscience Says

Pre-exhaust is a technique where you do single joint (isolation) exercises before multi-joint exercises. For example, with chest you first do flyes or cable crossovers. Then you follow with multi-joint exercises, such as barbell or dumbbell bench presses. The purpose of pre-exhaust is to ensure that the target muscle receives the maximum muscle growth stimulus during the multi-joint exercise.

Since multi-joint exercises involve the help from other muscle groups—for the bench press the shoulders and triceps are also major players—the target muscle group often doesn't get adequately stressed. Often you reach muscle failure on a multi-joint exercise when one of the smaller and weaker assistance muscle groups is fatigued and not when the target muscle group is truly fatigued. This can limit the muscle growth you get in that muscle.

By doing pre-exhaust you exhaust the target muscle group—in this case, the pecs—so it is the weak link on the multi-joint exercise, and you truly end the set when the target muscle group is fatigued. This can help to increase muscle growth in that muscle.

Published Science Says

Two studies from two different labs have investigated the benefits of pre-exhaust, one looking at pre-exhaust in the quads and the other looking at pre-exhaust in the pecs.

In the leg study, Swedish researchers had subjects do the multi-joint exercise the leg press either before doing the single joint exercise the leg extension or after. In the chest study, Brazilian researchers had subjects do the bench press either before or after doing the single joint exercise the pec deck.

In the leg study, they reported that the muscle activity of the quadriceps muscle fibers when subjects did the leg press after the leg extensions (pre-exhaust) was significantly less than when they did the leg press first. The researchers in the chest study also found similar results. They reported that the muscle activity of the pecs was significantly less when they did the bench press after doing the pec deck (pre-exhaust) than when they did the bench press first. But research groups concluded that this proves that pre-exhaust does not work. They claim that this is because it did not increase muscle activity of the target muscle group during the multi-joint exercise.

Unfortunately, the Brazilian and Swedish researchers are misinformed regarding the reason why bodybuilders use the pre-exhaust technique. Pre-exhaust was not designed to increase muscle activity of the muscle of interest; it was created to increase the fatigue of the muscle of interest, hence the name. Therefore, these two studies showing that the pecs (Brazilian study) and quads (Swedish study) experienced a decrease in muscle activity during pre-exhaust proves that it works for what it was designed to do – exhaust the target muscle. When a muscle becomes fatigued, it decreases muscle activity.

Yet another, more recent study, also tried to disprove the benefits of pre-exhaust. In it, researchers attempted to look at the true training effects of pre-exhaust over a 12-week period. Before we take a look at some of the fatal flaws that made this study completely useless, let me tell you briefly what they did and what they found.

The study was performed by researchers from the UK along with the American-based fitness facility Discover Strength in Plymouth, Minnesota. They had 39 male and female "trained" subjects (I'll get to the "trained" part as well as more detail on these subjects in shortly) split up into three different groups.

Group 1 was considered the "pre-exhaust" group. They performed the following workout twice a week for 12 weeks: One set of machine flies supersetted with one set of machine chest press; one set of leg extensions supersetted with one set of the leg press; one set of the machine pullovers supersetted with one set of pullovers; and finally, one set of machine crunches supersetted with one set of machine back extensions. That's it! They did take each set to muscle failure, though. (More to come on the "one set" and "superset" mentions.)

Group 2 did the same exercises in the same order but were allowed to rest for one minute between each exercise. Group 3 did one set of all the compound exercises (in this order: chest press, leg press and pulldown); then one set of all the isolation exercises (in this order: machine fly, leg extension, and pullover); followed by machine crunches machine back extensions.

After 12 weeks of performing this workout of one set per exercise, the researchers reported in a 2014 issue of Applied Physiology, Nutrition and Metabolism that there was absolutely no difference between any of the groups in terms of muscle strength or body composition (muscle mass gain or fat loss). All groups saw significant gains in muscle strength but no change in muscle mass or body fat. They concluded that pre-exhaust is a completely useless training technique.

Before you go off believing that pre-exhaust was just proven to be useless, wait one minute. As I mentioned earlier, this study had many fatal flaws. Let's break these down:

Problem #1: Age of the Subjects

The mean age of the subjects was 49 years old. The age range of the subjects was 36-62! There's a reason why most training studies use young male subjects: They respond far better to exercise. Older people simply don't respond as well. Plus, any well-designed study picks a fairly tight age range because age can have a dramatic impact on results. Such a wide age range and old population looks to me like they were just trying to get any subjects they could for the experiment. That's not how you do a well-designed study.

Problem #2: Gender of the Subjects

30 of the 39 subjects were female and only 9 were male -- more than three times as many females as males! If you're going to study both genders, you typically attempt to get a fairly even distribution. This again shows that they were just trying to get anyone to participate.

Problem #3: Training Status of the Subjects

The researchers stated that the subjects were "trained." Yet they further stated that "trained" meant at least six months of training experience. The last time I checked, someone with six months of training experience under his or her belt is an intermediate at best, and likely still a beginner as far as strength-training research goes. Most well-done strength-training studies use two years as the cut-off point for being considered "trained."

This a problem because untrained (or very inexperienced) subjects usually make significant gains in strength yet little gains in muscle mass. And that's exactly what the researchers reported. Despite only doing one set of each exercise, they still made significant strength gains whether they did supersets of isolation exercises followed by compound exercises, rested between all sets or did all compound exercises first and then all isolation exercises. Typically, only beginners or newbies would respond this same way.

Problem #4: Description of Pre-Exhaust

The researchers explained pre-exhaust as doing an isolation exercise immediately followed by a compound exercise without any rest between the two exercises. What they described is an advanced technique of pre-exhaust called "pre-exhaust supersets." Pre-exhaust in its typical form is more like what Group 2 did: Do an isolation exercise first, rest a minute, then do a compound exercise. The fact that they don't understand what pre-exhaust is makes me wonder what they really know about training.

Problem #5: Only One Set per Exercise

How could anyone design a strength training study and use only one set per exercise?! One set per exercise and only two exercises per muscle group is NOT a training program. It's a warm-up. Hence, the study is useless.

Problem #6: The Whole Point of Pre-Exhaust Is Completely Missed Here 

Pre-exhaust isn't any better than any other training technique. Pre-exhaust is DIFFERENT from most other training techniques. That difference is important when you've been doing the same style of training for a long time -- years, even decades. That's when pre-exhaust is beneficial. It's not a question of whether or not pre-exhaust is better than another training technique. You don't stick with one training technique indefinitely. Variety is the key to making continued progress in the gym.

Winner: Broscience

Do this: Tell the scientists to leave the lab every once in a while and pick up a weight. Clearly, they have no idea what pre-exhaust is and therefore should not be studying it in the lab! Your best strategy is to do multi-joint exercises first in your workouts for the majority of workouts. This will allow you to use the most weight on the multi-joint exercises so you can place more overload on your muscle fibers for greater growth. However, using pre-exhaust from time to time is a good technique to spur some new muscle growth.


Supporting Research

Augustsson, J., R. et al. Effect of pre-exhaustion exercise on lower-extremity muscle activation during a leg press exercise. J. Strength Cond. Res. 17(2):411–416, 2003.

Gentil, P., et al. Effects of exercise order on upper-body muscle activation and exercise performance. J. Strength Cond. Res. 21(4):1082–1086, 2007.

Westcott, W. Strength training for life: Make your method count. Nautilus Magazine 5(2): 3-5, 1996.

Fisher, J. P., et al. The effects of pre-exhaustion, exercise order, and rest intervals in a full-body resistance training intervention. Applied Physiology, Nutrition and Metabolism, In press, 2014.

Does the Mind-Muscle Connection Exist?

What is the mind-muscle connection? It's the ability to focus so deeply on a muscle that you can increase the number of muscle fibers you are using in that muscle and therefore get better results in muscle growth. You can also use it to contract a muscle with more force, allowing you to be stronger. Research has shown that both examples are possible and real. Yet some skeptics feel that this concept is not real science and is just "touchy-feely" nonsense invented by bodybuilders in the 70's

Broscience Says

Bodybuilders have long understood that to get serious muscle growth you can't just haphazardly go through the motions when you train. Not only do you need to train with relentless intensity, but you also need to train with serious focus. For example, when doing a barbell curl, you need to have a laser-like focus on the biceps muscles contracting with each and every rep. It's not enough to just let your muscles move the weight, you really need to connect with the target muscle for best results.

Published Science Says

No scientist in his right mind would ever admit that thinking about a muscle as it contracts can enhance its growth. It's just too abstract a concept for those who need hard data to make a conclusion. Of course, I am not one of those scientists.

I have always understood the importance of the mind-muscle connection, even if there wasn't any data to support it. It's one of the most critical things I learned from Arnold. He was a big believer in the mind-muscle connection, as well as visualization. Luckily I'm not alone in being a scientist who believes wholeheartedly in this abstract concept.

A very forward thinking research lab in the UK attempted to investigate if the mind-muscle connection was a viable concept. Researchers from Edge Hill University had trained lifters do 10 reps of one-arm biceps curls on three separate occasions. During one trial, they performed the curls as they normally would with no particular focus (i.e. just going through the motions). In another trial, they did the curls while focusing on the contraction of the biceps muscles with each rep. In a third trial, they did curls while focusing on moving the weight during each rep.

They discovered that when the subjects focused on the contraction of their biceps while doing curls, the muscle activity of the biceps was increased by more than 20%. Although this doesn't prove that the mind-muscle connection can increase muscle growth, a greater increase in muscle fiber activity could lead to enhanced muscle growth over time. They also found that when the subjects focused on moving the weight while doing curls, their muscle strength was increased by about 10%.

Winner: Broscience

Although one laboratory supports the reality of the mind-muscle connection, few researchers would be willing to agree that it's a real thing.  It is true that Arnold and his gang of training partners like Franco Columbo, Frank Zane, and Dave Draper were big believers in this concept. Clearly, it worked for them and it can work for you. Forward thinkers, like you, me, and Arnold know it is very real.

Thankfully, real science is catching up to those of us already in the know. One more recent study showing how the mind-muscle connection can work, and how you can fine tune it, comes from the University of South Carolina Upstate.

The researchers had weight-trained football players perform 3 sets of bench presses using their 50% rep max weight (that's a weight equal to 50 percent of their one-rep max weight, or a weight that they could do for a little more than 20 reps) and 3 sets using their 80% RM (a weight that they could do for about 7-8 reps).

During each bench press set, they measured the muscle activity of the athletes' pecs, triceps, and front deltoids. In the first set, they were given no instructions. In the second set, they were told to use just their chest muscles. And in the third set, they were told to use only their triceps muscles.

When the athletes used the lighter weight (50% RM) and were instructed to use just their chest muscle, the muscle activity of their pecs increased by 22% compared to when they had no instructions.

When they were told to use only their triceps while lifting the lighter weight, their triceps muscle activity increased by 26%. During the heavier lift (80% RM) the increase in muscle activity of the focused muscles was not as significant. They concluded that focusing on a specific muscle during exercises such as the bench press can increase the number of muscle fibers used in that muscle, but that this may be more effective with lighter weight.

Do this: The mind-muscle connection is important, so use it well. But it's important to know how to focus on the specific goal.

To enhance muscle growth, focus on the target muscle as it contracts with each rep. This is known as internal focus. You need to block out your surroundings and really try to connect with the target muscle. Wearing headphones with your favorite music playing can help tremendously to block out your surroundings and focus deep into that muscle. Think about the muscle fibers getting shorter as they contract. Then hold the peak contraction for a second and focus on flexing the muscle as hard as possible. Then as you lower the weight, focus on the muscle fibers slowly lengthening as they resist the weight.

To enhance muscle strength, focus on moving the actual weight through each rep and not on the muscle contracting. This is known as external focus. Your goal is to focus on the object you are moving. This can help you to lift more weight on a one-rep max attempt an help you complete more reps with a given weight.

When lifting with heavier weights (sets where your rep range is 8 reps or less) focus on lifting the most weight. Because the weight is fairly heavy your body will need to focus on recruiting as many muscle fibers from as many muscle groups as possible to lift it. And focusing on lifting the weight can help you to get significantly stronger.

When using lighter weight, sets of about 10 reps and above, focus more on the target muscle group being used. This can increase the number of muscle fibers being used specifically by that muscle during the lift. And the more muscle fibers you are using the greater the muscle growth you can expect in the long run. Using my Micro Muscle program as an example, during microcycles 1 and 2 focus on each target muscle during each set. Then in microcycles 3 and 4 focus on lifting the weight. This will help you gain more muscle mass and get stronger at the same time.


Supporting Research

Merchant, D. C., et al. Attentional focusing instructions influence force production and muscular activity during isokinetic elbow flexions. Journal of Strength and Conditioning Research 23(8): 2358-2366, 2009.

Marchant, D. C. Attentional focusing instructions and force production. Front Psychol. 2010;1:210. Epub 2011 Jan 26.

Marchant, D. C., et al. Instructions to adopt an external focus enhance muscular endurance. Res Q Exerc Sport. 2011 Sep;82(3):466-73

Snyder, B. J. and Fry, W. R. Effect of verbal instruction on muscle activity during the bench press exercise. J Strength Cond Res. 2012 Sep;26(9):2394-400.


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