As you know, for muscle growth you need to build in enough rest between sets: 1-2 minutes for isolating exercises, 2-3 for most compound exercises and 3-5 for squats and deadlifts. If you rest less, this will affect the quality of the set, namely the number of stimulating reps you could do with a certain weight. But can you also rest too long between sets, at the expense of muscle growth?
The answer: no, unless. We will discuss the ‘unless’ below.
If you rest for a long time between sets, for example because you are bro-chatting a lot, you risk that your body will cool down too much. In that case, you will have to do another warm-up set before you can start your next work set. Not efficient, but if it only happens occasionally, it’s not a disaster.
Doing nothing unnecessarily long between sets is also not an efficient way to manage your time. Resting longer than 1-5 minutes (depending on the type of exercise and intensity) has no added value, so why bother? Your training should be finished after one to one and a half hours. That usually equates to 15 to 25 sets in total.
If you rest ‘normally’ between sets one time and the other very long, it is difficult to track your progress accurately. Because after ten minutes of rest you will probably grab an extra rep, but if you rest only two minutes next time, you take another step back.
Therefore use fixed rest times. You don’t have to be precise: if you’re able to sense when you’re ‘ready’ for your next set, that’s okay. ‘Ready’ means that all types of fatigue (local, central and cardiovascular) have been sufficiently resolved.
Do you normally use short rest periods because you usually have little time to train? Use it even when you do have a lot of time.
Being too busy with ‘other’ things during your sets, such as social media, also takes a toll on your focus. Try to stay focussed on the here and now – your training – as much as possible. Feel free to work your training log happy and go for a walk. The latter may even contribute to your recovery if you do leg training (if you train your upper body, you can swing your arms a bit). Or just sit down, put your phone aside, stare and think about the target of your next set.
From research we know that mental fatigue, for example due to everyday concerns, may reduce exercise performance by 15%. Therefore, try to start your training as relaxed as possible. And don’t try to solve relationship problems between sets.
Post-activation potentiation, in short PAP, or the phenomenon whereby an athlete performs better in a certain activity if another (heavy) activity has preceded it. For example, better performance during the long or high jump by squatting prior to this.
The big question is to what extent this phenomenon also occurs in pure strength sports: if you start your next set at the right time, are your muscles just a bit stronger than if you wait longer? Unfortunately, that question is difficult to answer, despite the fact that PAP has already been extensively researched.
However, we think that something of PAP does play a role in hypertrophy training. Have you ever noticed that the second set of an exercise went better than the first? Even though you were still completely fresh for the first set? This is probably because your nervous system, muscles and joints work more efficiently to move the weight the more sets you do. You create momentum so that you can deliver more net power. You can also probably achieve a better mind-muscle connection after your first set. It is for good reason that we always recommend doing at least two sets of an exercise in a row.
If you rest very long after a set, you lose that momentum. So it seems like the trick is to start your next set when the fatigue has resolved sufficiently while you’re still in the momentum. So best of both worlds. And that’s something that requires training experience, although the general guidelines seem like a good starting point for that (so 1-2 minutes rest for isolation exercises and 2-5 for compound exercises).
METABOLIC STRENGTH TRAINING
If you’re training for muscle growth, getting plenty of rest between sets is essential for the quality of those sets. That quality is determined by the amount of mechanical tension you create especially through the stimulating repetitions just before muscle failure. If you rest too short, there may still be too much fatigue to achieve optimal mechanical tension.
In addition to mechanical stress, there may be another way to create growth stimuli, namely through metabolic stress. That is the accumulation of metabolites that mainly occurs when you do a lot of repetitions and/or use short rests and/or apply special techniques such as supersets. One of the indicators of metabolic stress is the so-called muscle pump you experience. So it is not the muscle pump itself that produces the growth stimulus.
Metabolic strength training is especially suitable for people who do not train primarily for muscle growth, but who find fat loss and fitness improvement at least as important. It is still unclear to what extent bodybuilders benefit from this form of training (in addition to regular strength training). One muscle group may respond better to it than another, coach Mike Israetel says.
In any case, if you do metabolic strength training, long rest periods are out of the question: you consciously choose not to “clean up” all fatigue and thus maintain muscle pump.
CONCLUSIONS AND ADVICE
1. If you’re training for muscle growth mainly, getting enough rest between sets is essential for the quality of those sets. That quality is determined by the amount of mechanical tension you create through especially the stimulating repetitions just before muscle failure.
2. Only start your next set when you feel completely ready physically and mentally: you must be able to use all your available power and achieve a good mind-muscle connection. To this end, all fatigue from the previous set must be sufficiently resolved: the local fatigue (in both the target and auxiliary muscles), the central fatigue and the cardiovascular fatigue.
3. If you find it difficult to feel when you are ready for your next set, use as a guideline: 1-2 minutes for isolating exercises, 2-3 for most compound exercises and 3-5 for squats and deadlifts.
4. Use more or less fixed rest times between your exercises, so that you can keep track of your progress in a clean way.
5. Resting longer between sets, for example because you are distracted, usually won’t really hurt muscle growth. Resting too short is much more harmful than resting too long.
6. However, don’t make a habit of long rest periods, as they can negatively affect your training performance: you cool down too much causing you to do extra warm-up sets, you lose focus and/or you may not benefit from the momentum of several sets within a specified period of time. Apart from that, you spend unnecessarily long in the gym.
7. If you do metabolic strength training, you consciously use short rest periods. Resting for too long then detracts from the accumulation of metabolites that you are deliberately trying to achieve. However, metabolic strength training is not the most effective way of training for muscle growth. To this end, it is better to use longer rest periods, in order to create maximum mechanical stress. Metabolic strength training may be a useful addition for bodybuilders though.