The Science Behind the Drop Set & Muscle Growth

It’s 5 o’clock and your wife and kids are expecting you home at 5:45 to help with dinner, leaving you nowhere near the time necessary to execute your entire lift with appropriate warm-up, rest periods, and tempos.

The question is what do you do?

You could go hit some intervals on the rower and do some abs for conditioning, not a bad option.

You could totally blow off the workout and pick up some roses on your way home and handle dinner all by yourself, scoring big time points with your wife, also a decent choice.

But the problem is, none of those options will get you any closer to the superhero physique you envisioned for yourself when you started your current workout program.

The fact is, when trying to grow muscle, you can't skimp on the training volume and expect optimal results¹.

Obviously, the more training volume, the more time spent in the gym, the less time you spend earning points with your lady.

It would seem like an insatiable appetite for muscle growth and only 30 minutes to lift spells SOL.

That is, until the busy lifter’s best friend crashes the party: drop sets.

What are Drop Sets?

Traditionally, a drop set is performed by taking an exercise to momentary muscular failure and then decreasing the load and hitting failure again.

Frequently, multiple drop sets are used to increase greater muscular fatigue and as a result, create more hypertrophy (muscle growth). The only rest between drop sets is the amount of time it takes to change the weight.

Related: Drop Sets - How to Use Drop Sets For Strength & Hypertrophy

In performing multiple drop sets, the lifter can increase time under tension (TUT), metabolic stress, ischemia, and total volume in less time than it would take to finish straight sets of heavy work.

Let Me Drop Some Science

Until recently, drop sets have been more broscience than real science. Nothing says meathead like failing on an exercise, lowering the weight so you can fail again, and repeating until your muscle can no longer fire with your 1000 rep max.

However, thanks to some recent research, meatheads everywhere are rejoicing at the findings of a few studies designed to determine if this widely used technique is legit. In super scientist Brad Schoenfeld’s recent paper on this very topic², an abundance of literature concerning the use of drop sets were discussed.

Two of the studies drew conclusions that justify the use of drop sets when muscle hypertrophy (size) is the goal. In both studies, the total time of the lifters that used drop sets reported that they spent less than half the time in the gym as their straight set counterparts.

In a study performed by Fink et al.³, 16 men were split up into 2 groups and given different strength protocols over 6 weeks. One group did a traditional 3 sets of 12 reps with 90 seconds rest on a tricep pushdown.

The other group did 1 set of 12 that included 2 drop sets for the same exercise. With the same amount of training volume across both groups, the drop set group’s triceps responded with almost 2x the growth after 6 weeks!

In another study by Ozaki et al⁴, participants were split into 3 groups and given different protocols over 8 weeks. Each participant bicep curled either a heavy weight with long rest, light weight with moderate rest, or a heavy weight with 4 drop sets.

All groups compared similarly in terms of hypertrophy even though the drop set group took considerably less time executing the protocol! Limited time in the gym doesn’t always have to mean limited gainzzz!

Practical Application of the Drop Set

While both studies support the use of drop sets, my guess is there exists a point of diminished returns. Pushing a muscle to failure multiple times in a workout and then doing it again a few days later to the same muscle may lead to overtraining, decreased recovery, or frying your CNS.

Use drop sets strategically over the course of the week for best results or to avoid being served divorce papers when you’re on your 8th set of your 5th chest exercise while you were supposed to be home hours ago.

Related: Fast Mass Program - The 4 Day Superset Split Workout

Perform a drop set with multiple drops (up to 3) on a muscle (or muscle group) no more than 2-3x a week to enjoy the best ROI.

In my experience, especially when training without a spotter, weight selectorized machines provide the best opportunity to use drop set training. Using a fixed ROM on a machine will help you keep form and decrease injury risk during severe muscle fatigue and allow for maximum activation of the targeted muscle(s).

This also allows the lifter the shortest recovery time between drops (due to the ease of switching the pin) while changing the load causing more metabolic stress. In terms of load, each drop should be at least 25% of the previous load or sometimes more depending on the targeted amount of reps (e.g. 100lb chest press, drop to 75lbs, then 50lbs etc.).

When choosing an exercise to perform drop sets, isolation movements may be better at fatiguing specific muscles (and promoting hypertrophy) than compound movements. While a drop set on a compound movement may provide more systemic fatigue, the drop set on the isolation exercise will focus more specifically on exhausting each fiber in the targeted muscle.

Using the quads as an example, a leg extension would be a much more efficient exercise to employ a drop set than a barbell back squat.

For the squat you will certainly be exhausting your quads, but due to the amount of muscles involved in the movement (hamstrings, low back extensors, glutes, etc.) it becomes a challenge to focus on which muscle fails first.

That’s not to say a barbell back squat drop set isn’t effective because it is, but when discussing quad hypertrophy, the leg extension wins out hands down.

Wrap Up

Drop sets have always been a fun and painful way to create serious muscle damage, however it’s good to know that we have more evidence than bro-science that backs it up as a way to enhance hypertrophy.

There is no substitute for intense traditional straight set training and focusing on progressive overload consistently in your strength program, but drop sets can prove quite handy when faced with a time constraint or to get some added volume without adding much total gym time.

While they are to be used with caution, drop sets are a great tool to have in the lifting tool box, especially when the clock is ticking.