The purpose of this study was to determine the effect of exercise order on 1 RM strength and muscle thickness, over the course of a 12 week training program. Essentially, this study is attempting to determine if you should in fact, place the most important exercises (to you) first in the lineup of exercises. Doing so theoretically should improve growth of those target muscle groups since you're fresh and not fatigued, allowing you to put forth greater effort (power production, total volume, the weight you use, etc).
Why Study This?
This is important to study because based on the findings of this study, exercise order may or may not be extremely important. For example, if placing the barbell squat before leg extensions meant DOUBLE the growth of your quadriceps muscle, compared to the opposite order, which would you choose?
Studies like this allow us to understand if the order you complete exercises makes a difference for the target outcome. The findings of research studying this concept could literally shape program design for almost every individual that wants to lift weights or exercise.
See, the back squat allows for an incredible amount of volume, per repetition. Essentially, the squat provides you with the largest and strongest muscle building stimulus, so it makes sense for those to be first. Many people consider the use of pre-exhaustion (using small muscle exercises first) as a means of stimulating growth, but really, you're just reducing the amount of work you can do with the compound movements, which is suboptimal.
31 male Brazilian Navy Sergeant students were recruited to take part in this study. These subjects were not traditionally resistance trained but were of military grade athleticism. After recruitment, subjects were placed into 1 of 3 random groups:
Large muscle group exercises would be considered compound movements, like the squat, bench and deadlift. Small group exercises would be like a dumbbell biceps curl or any other isolation movement.
At the beginning and end of the study, 1 RM assessments were completed. Further, muscle thickness assessments were taken with the use of ultrasound. Ultrasound is one of the gold standard methods of assessing changes in muscle thickness as a result of resistance training. In fact, I've been exposed to this procedure on multiple occasions during my time at The University of Tampa.
Resistance Training Protocol
The following exercises and exercise orders were completed during this study:
Participants completed these exercises using a linear periodization method, exercising 2 times per week, separated by at least 72 hours.
"From the first to the fourth week, four sets of each exercise were performed with light intensity (12 to 15 repetitions) with one minute of rest between the sets. From the fifth to the eighth week, three sets of each exercise were performed with moderate intensity (eight to 10 repetitions) with two minutes of rest between the sets. From the ninth to the twelfth week two sets of each exercise were performed with high intensity (three to five repetitions) with three minutes of rest between the sets."
As you can see above, there were some mixed findings.
Essentially, this table is telling us that when compound movements were placed first in the workout, the changes observed for compound movements was greater than the changes observed when small exercises were placed first (for the compound movements).
Alternatively, the group placing small muscle group exercises first, observed more pronounced changes for small muscle group exercises than did group 1.
When it comes to muscle thickness, there was not a profound effect as a result of the training program. Above we can see that the only meaningful changes was in triceps muscle thickness, which was observed in group 2 (small groups first).
Regardless of the magnitude of the change, these findings are in line with the underlying theory of exercise order.
Despite No Strong Findings, They Do Reflect The Current Theory
Even though the findings were astounding, there still was some significance, which reflect the idea of exercise order impacting growth. Based on these findings, if a more rigorous training program were to be utilized, I'd wager the findings would be far more significant.
Things May Be Different For Beginners
As just mentioned, the training was a bit subpar, which is typical for studies like this. These subjects only trained twice per week, which isn't very much. Sure they used a periodization model, but this doesn't necessarily reflect real life.
To really study this sort of subject, we need trained weight lifters that regularly complete compound movements to be used for this type of thing. Consider for a moment that new beginners will likely fatigue fairly quickly when resistance training, regardless of the exercise being used.
When looking at trained individuals, the typical amount of weight they'll use for compound movements will likely be significant and quite fatiguing. This means that the order of exercises will be very significant. For example, a trained person will likely be able to bench 3-4 times as much as they can bicep curl, meaning that they'll require peek muscle ability during those compound movements.
For a beginner however, the gap between bench strength and biceps curl strength likely won't be massive. This means the order of the exercises won't have as large of an impact on each other, as say would a very experienced lifter.
The Underlying Theory Is Sound
Here are two scenarios that you can consider when evaluating the theory of exercise order.
1. Let's say that your goal was to produce a maximum amount of strength for the back squat. A true 1 Rep Max Test. When you're attempting to complete this feat of strength, would it make sense to complete a full workout of isolation movements, beforehand? Likely not, since it would lead to immense fatigue, resulting in a subpar performance.
2. Your goal is to increase the size of your legs entirely. You have both the back squat / other squat variants of squatting with a barbell, plus isolation movements such as leg curls and leg extensions. For the purpose of increasing muscle size as a whole, which order do you place them in? You need to consider that total volume (weight x reps x sets) is a driving factor in muscle growth. So which exercises will give you the most bang for your buck?
If you answered squat, you're probably right. See, the back squat allows for an incredible amount of volume, per repetition. Essentially, the squat provides you with the largest and strongest muscle building stimulus, so it makes sense for those to be first. Many people consider the use of pre-exhaustion (using small muscle exercises first) as a means of stimulating growth, but really, you're just reducing the amount of work you can do with the compound movements, which is suboptimal.
Based on the findings, it makes sense to place priority muscle groups first. This also extends to the purpose of your exercises as well. I suggest that you decide on target muscle groups and target muscle purpose (build muscle, increase strength, etc.) before going to the gym and letting your intended result drive the exercise order.
Overall, you should place the most important (to you) exercises first, followed by secondary muscle groups and focuses.
Why This Should Matter To You
It should matter because this sort of research may drive how you structure all of your workouts. Further, it helps shed light on the most optimal ways to train, which eventually improves everyone's ability to get in better shape, faster.