Resting for Strength GainsYour body isn’t aware of your goals or your timelines. It is in charge of managing and orchestrating a variety of physiologic processes that it adapts to meet the demands of your environment as best it can, irrespective of any notions of success or your preferred level of impatience. There are limits to how quickly your body can perform these functions. It needs rest between bouts of effort to perform at its best and to adapt to long-term habits.
Resting for Strength Gains
By: Noah Hayden, Staff Editor
For a committed lifter, it’s easy to make the mistake of excess. Cram in as much work as possible because more is better, right? (I think our modern work culture of perpetual growth predisposes people to overwork or feel guilty about being lazy, but I digress.) Unfortunately, when it comes to strength training, excessive training is a short path to stalled progress, and a more is better attitude will often lead to a plateau, injury, or backsliding.
Your body isn’t aware of your goals or your timelines. It is in charge of managing and orchestrating a variety of physiologic processes that it adapts to meet the demands of your environment as best it can, irrespective of any notions of success or your preferred level of impatience.
There are limits to how quickly your body can perform these functions. It needs rest between bouts of effort to perform at its best and to adapt to long-term habits—intentional or otherwise. If you want to sustain progress over many years, you will need to give your body time to keep up with your training sessions. This applies to programming and lifestyle in the long term—adjusting frequency, volume, intensity, nutrition, and recovery to match your body’s rate of adaptation. In the very short term, too little rest may prevent you from completing the sets and reps of a single workout, potentially interrupting steady progress and undermining the value of that workout. Taken too far, not respecting the rest between sets within your training sessions can cause longer-term problems with training. Let’s explore short-term considerations.
Different Types of Metabolism
Your body seamlessly utilizes a handful of different metabolic strategies to allow you to move in the ways you’re accustomed to. The easiest way to categorize these is into two groups: aerobic and anaerobic—those that require oxygen to function and those that don’t, respectively. These categories are a bit misleading because your cells are always in the presence of oxygen. It’s important to remember that all of these pathways are constantly functioning, and your body is always using oxygen, but thinking in terms of which pathways are primarily being exploited at a given time can help us make better decisions about what training habits we should be cultivating.
All cellular work in the human body is performed with ATP (adenosine triphosphate). This molecule is cellular currency—the only currency cells can use. During a lift, our muscles need to perform a lot of work relatively quickly, which means the muscle cells need a lot of ATP. The phosphocreatine and fast glycolytic energy systems (i.e., anaerobic energy systems) are perfect for this situation. They can provide a huge amount of ATP to muscle cells, but the tradeoff is they can only do so for a short time. After that, they need to recharge before another bout.
As ATP is used by muscle cells, creatine phosphate almost instantly replenishes the supply. This leaves creatine to be recharged with another high-energy phosphate back in the mitochondria—the home of aerobic systems. Anaerobic glycolysis also produces ATP quickly, but the process is not sustainable. Large amounts of lactate result, and once these levels build up enough, glycolysis cannot continue until the lactate is dealt with. Aerobic energy systems process this byproduct to make another intense effort possible.
These aerobic pathways are at the other end of the metabolic spectrum: offering relatively slow ATP replenishment (and at lower levels) but for a virtually unlimited amount of time. Although this ability isn’t immediately helpful in the context of strength training, these pathways are critical to restoring the conditions necessary for the next “anaerobic” training effort. These different metabolic pathways are not independent of each other. They work together to provide the movements of life. The key point is, they need time to accomplish their task.
We need to rest between sets because aerobic metabolism is required to replenish anaerobic pathways. Aerobic metabolism needs around two minutes to start providing that support. The total amount of time needed to be prepared for the next set depends on several factors: how intense the last effort was (how much ATP was used), how recovered you were from previous efforts, how skilled you are at grinding through reps, how intense the next effort will be, and how prepared you want to be for the next effort (more on this later).
Rest in Practice
You can determine each of these factors easily. Take note of your respiration and heart rate before your workout begins. Think of this as your resting rate. After a work set, your respiration and heart rate will be elevated. For conventional strength training, you should rest long enough before the next work set that you return most of the way back to your resting rate (~90%). You could actually measure this, but that level of precision isn’t necessary. Within a few sessions, you’ll know what it feels like when you’re close to your resting rate. This will take at least three to five minutes.
Warmups don’t require any significant rest periods because they shouldn’t be fatiguing by design. If you find you require more than a short rest between heavy final warmups, you’re probably not warming up properly.
The more advanced the lifter, the more deeply they will be able to deplete their anaerobic capacity, and this will require more time to replenish. Seven to ten minutes is not uncommon. That same lifter may take a little extra time before an especially challenging PR attempt, knowing they will need all the anaerobic capacity they can muster.
Conditioning is a different story. When trying to challenge our aerobic capacity, we intentionally restrict rest periods, so anaerobic systems aren’t comfortably recharged between bouts of effort. For HIIT, not resting more than two minutes per round is a good starting point. This same approach applies to hypertrophy work as well. If the goal is muscle failure (or closer to it), restricting rest periods helps achieve that exhaustion.
To the new lifter, rest periods may seem like a waste of time, but your body isn’t really resting between sets. It’s feverishly working to replenish ATP in a relatively short amount of time. Think about your breathing, and make sure you’re utilizing all of your lung tissue during this aerobic phase of recovery. Remember, if you’re moving around a lot during rest periods, your body now has divergent tasks to handle: ATP replenishment and motor performance. Don’t sabotage yourself! Allow your body to complete one task at a time.
Also, your brain is not resting. Your mental responsibility during training is technique execution, and rest periods are a perfect opportunity to review and critique the last set, formulate a plan for the next set, and focus on the cues needed to make that happen. If your form is decent, this might not require all of your attention, but this is still a good habit to maintain for when it’s needed. Besides, is scrolling through social media that important?
Resting is not a passive activity. It should be approached with the same procedure and ritual as the rest of your lifting routines because it can easily be the difference between a miss and maintaining progress. If you are grinding through reps or stalling—especially with novice programming—rest a couple of minutes longer and see if your performance improves. It might be that simple of a change to get back on track.