During our workouts, when we think about rest we typically think of taking a window of opportunity to breathe between exercises, reps or even sets. When we’re focused on an objective, it’s easy to pay the most attention to the work we’re doing in each set. However, to achieve these objectives, we should also keep in mind the rest between sets of exercise.
The science behind needing rest.
Strap yourselves in!
As we know – we need to eat to fuel our bodies to help them perform, function and conduct their daily activities in order to keep us alive. Now let’s take this same principle and apply it to our muscles during exercise. Muscles are fuelled by three energy systems: The Phosphagen System, The Anaerobic (Glycolytic) System and the Aerobic (Oxidative) System. As our muscles begin working harder during physical activity, these systems take turns leading the way to synthesise our food sources (fuel) to Adenosine Triphosphate (ATP aka. Energy), providing energy to muscle cells, in turn contracting and producing movement.
The Phosphagen System and The Anaerobic (Glycolytic) System work for shorter durations, meaning they provide high force production for a short amount of time, think explosive movements! The phosphagen System provides muscle energy for up to 30 seconds of work, after that the Glycolytic System provides energy from 30 seconds onwards to roughly 3 minutes and is involved in moderate force production activities, think strength days! As exercise duration begins to surpass the 3 minute mark, the Aerobic System takes over and is involved in lower force production activities, think cardio!
Now we know this and our energy source has been utilised, we’ll need to find a way to allow our bodies to produce more energy to repeat the same activity with the same intent (e.g lifting the same weight again for a second set / producing the same amount of force) … that’s where rest comes in!
How long should I rest during my workout?
Let’s take a look at this in terms of MOVE Headquarters and our POWER, PERFORM and SWEAT days.
Firstly, POWER & PERFORM are days that typically include some lifting. Our previous blocks have targeted principles like muscular strength, to increase our overall strength as well as hypertrophy. In order for muscle fibres to grow in size, they need to be stimulated. The objective here is to overload the muscle and cause temporary trauma to the muscle fibres, hence why we feel sore. This results in muscle fibres being stimulated to grow and increase their cross sectional area. These loads placed on the muscle typically range from 50-90% of our 1 rep max. Studies have shown that to induce muscle hypertrophy, optimal rest intervals are between 30-90 seconds.
When talking more about muscular strength, we are referring to the ability to produce force to move a weight, thinking back to our recent POWER block. Power = Strength x Speed. When we are building strength, adequate rest between sets is needed in order to maintain a high level of force production. Thus, typical rest periods for increasing strength are between 2-5 minutes, which research shows to be optimal for strength development. However, it should also be noted that this may vary depending on factors such as age, fibre type and genetics.
Next – SWEAT! On our SWEAT days, we predominantly use our Aerobic System as our work periods are longer than 3 minutes and we aim to target our cardiovascular system. This can also be thought of as muscular endurance. Muscular endurance is defined as the ability to perform repetitions of an exercise over a period of time using a submaximal (lower) amount of weight or body weight. The National Strength and Conditioning Association (NSCA) recommends 30-second rest intervals between sets to improve muscular endurance. As you’ll have noticed from your training here at MOVE HQ, our SWEAT days are typically programmed with short rest intervals either between sets of the same exercise or through an AMRAP, this can be known as high intensity interval training (HIIT) that is beneficial to achieve muscular endurance.
With this being said, as coaches here at MOVE HQ, we encourage members to take rest as they need depending on how their body feels on that particular day and time! Honouring your body is the most important thing; and holding autonomy to your workout the whole way through.
As with all types of training, there is more to consider than just the exercises we are doing. We might want to consider things such as our training age (how long we’ve been training for) or executing a movement to improve ourselves technically. One study found that the greatest benefit for untrained individuals was allowing 60-120 seconds of rest between sets. The goal here is to allow enough time to recover in order to perform the next set as well as the first whilst maintaining good form.
A second consideration is technique, something I believe everyone can benefit from. Technique can be broken down to proper biomechanics of movement. Proper biomechanics increase our movement efficiency and decrease the risk of injury. It should also be noted that there is no time scale to perfecting form and technique, it is simply relative and varies depending on the exercise.
For example, Olympic style weightlifting (eg. Cleans), hones in on a skilled movement with rapid speed performance. Conversely, the amount of complex movement in a lift such as a bench press requires much less coordination of multiple body parts. Regardless of this, when trying to perfect form, we should focus on a lighter training load to allow our bodies to undertake the movement again with those good mechanics. In these instances, we would be looking at 1-2 minute rest intervals to allow for adequate rest and recovery.
The bottom line.
Regardless of what our goals are, when we are considering components of our training such as strength, force production and volume, it’s just as important to consider resting between sets as well as the exercises themselves.
Rest between sets should be sufficient to aid enough recovery in order to reintroduce the stimulus whilst still maintaining good form and technique. Depending on the goal of the session, we can shorten or lengthen the rest intervals to achieve the most out of our session.
References / Further reading