When I first started lifting weights back in 2004, supersets were considered a density method to be used sparingly. Most training done by either performance or aesthetic athletes largely consisted of doing separate exercises with ample rest in between. It’s also how I built most of my own strength and muscle later on. Fast forward to 2019, everyone seems to be running back and forth from station to station. Supersets and circuits are the new norm. While there is something to be said for this type of training, it may also hurt your progress. Allow me to explain.

Let's start with defining what a superset is. It is the performing of a set of two different exercises consecutively, with no rest in between. An example would be doing a set of bench presses immediately followed by a set of rows, before taking a break. And there are some benefits to it. With supersets you’re taking less rest, so training density is high - which is good for conditioning and cutting gym-time. Also, supersets that hit the same muscle group induce a lot of local fatigue, which is good for endurance and may trigger some growth. Sounds good, right? Get more done in less time. Very 2019'ish. But there’s a caveat.

A high training density (lots of continuous work, little rest) by definition means that intensity (defined as % of your max) will suffer. You just can't run a marathon at sprint speed. In the gym, when you’re doing balls to the wall squats, the two to five minute recommended rest break is there for a reason. You need to restore your energy systems, catch your breath, gather your senses, and refocus. Anything more than a stroll around the gym will take away attention and energy from the task at hand, and reduce your subsequent ability to perform work at high intensity. Now, this is not always a problem, so let's get to the when.

"A high training density by definition means that intensity will suffer."

If you’re relatively new to the iron game, the good thing is that your body is incredibly responsive to training. Take any novice, and usually weights of about 30% of their 1RM (one rep max) will already suffice for increasing coordination, strength, and muscle mass. What this means is that weights don’t need to be very heavy in order to get the gain train going, and that supersets and circuits are vastly effective. Maximal performance just isn't important for getting results. Not yet.

The more experienced you get, the higher the necessary training stimulus will need to be in order to induce progress. Take strength as an example. If the novice needs to lift only 30% of their 1rm to get stronger, a seasoned weightlifter may need to go as high as 85% in order for training to even induce adaptation. Anything below 60% is usually not even logged because it is considered part of the warmup. Since I have written before on why I argue strength to also be an important driver of muscle size, you should now start to understand why the biggest and strongest people at your gym are usually sitting around a lot in between their heavy work.

"The biggest and strongest people at your gym are usually sitting around a lot in between their heavy work."

Supersets work fantastically for novices or the advanced looking to boost their endurance. They also get a ton of work done in a short time, which is good for keeping space in our agendas. But important to keep in mind is that there is a point where too much high density training will water down training intensity, and this may hurt progress. Especially for those with a few gym-years under the belt.

My advice is therefore to definitely group exercises together in supersets when you're just starting out, but to gradually leave the heavier and more complex movements alone as you move along the curve of expertise. As a rule of thumb, I think anything over 80% of your one rep max or with more than your own bodyweight on the barbell is probably best trained separately. Use the time before and after such sets for recovering and refocussing, because only all hands on deck is going to cut it.