How does the Rest-Pause technique work?

Raúl Carrasco, our IFBB Pro, shows us how to perform a workout using the rest-pause technique.

The Rest-Pause technique divides a heavy set into several short sets and can be used in a variety of exercises, specifically to recruit those muscle fibers that are essential for maintaining muscle definition during a cutting phase or building muscle during a bulking phase.

For example, in a workout using the Rest-Pause technique, you rest for 15–30 seconds, then continue doing smaller sets until you effectively double the number of repetitions in the set or reach technical failure (muscular failure).

How to perform Rest-Pause

Warm up by doing 3 sets, increasing the weight with 3–5 repetitions per set to activate your central nervous system, and then move on to the Rest-Pause set.

Your rest-pause set will use approximately 85% of your 1RM, or a weight that allows you to perform 5–7 repetitions, depending on your strength levels and muscle fiber composition.

However, you can work with heavier weights if you are focused exclusively on strength rather than hypertrophy, so considering 85% of your 1RM as the ideal point for a combination of both seems ideal.

The warm-up would be:

• 65% x 5 = 93 kg.
• 70% x 5 = 100 kg.
• 80% x 3 = 250–115 kg.
• 85% = 123 kg.

Effective Rest-Pause set

• 123 kg x 6 repetitions, rest for 15–30 seconds, then …
• Do 1–3 repetitions and rest for 15–30 seconds.
• Then do 1–2 repetitions and rest for 15–30 seconds.
• Finish with 1–2 repetitions, or as many repetitions as necessary until you double the target number of repetitions.

At all times, you should feel your core during these sets and end your workout early if your repetition range is compromised or you reach technical or muscular failure.

Why Rest-Pause works Rest-Pause

If you lift heavier weight to perform more repetitions, you will provide the ideal stimulus for developing strength and size.

This is precisely what training with the Rest-Pause technique allows, as you will lift enough weight to train high-threshold muscle fibers and create progressive overload to increase your size and strength.

In addition, you will have enough rest to partially recover the adenosine triphosphate and phosphocreatine energy systems (ATP-PC) used to provide the immediate energy you need.

On the other hand, you will have enough rest to increase the metabolic stress that induces growth in subsequent sets.

The difference with Rest-Pause

Rest-Pause is a high-intensity technique in which brief rests within the set help ATP regenerate much faster.

Because phosphocreatine donates phosphorus, ATP can create a greater amount of ATP, and this happens quickly—in milliseconds…

In a regular set, once the ATP has been depleted, you will enter an anaerobic energy system directly, in which you will begin consuming internal glycogen based on the lactic acid you have. However, with these brief rests in the Rest-Pause technique, you will prevent this process.

Therefore, you will be able to extend the set and recruit a more internal fiber type (type II fiber), which is what interests us, without the problem of lactic acid production stopping us.

Imagine that we are cutting and our glycogen stores are empty; therefore, the production of lactic acid will be greater and more intense.

This will make us stop the set before the largest available fiber type is recruited. Consequently, within the same set, these brief rests allow us to replenish phosphocreatine in milliseconds—in this case, seconds, which we will discuss shortly.

Rest-Pause during a bulking phase

In bulking phases, you will follow a hypercaloric diet; therefore, you will want to gain muscle mass by taking advantage of the positive calorie balance.

Therefore, the Rest-Pause technique serves as a high-intensity technique for reaching and recruiting those type II fibers so that they can develop.

You should also remember that maintaining those short rest periods greatly increases one of the key factors, metabolic stress. In this scenario, you experience significant congestion, sweat more, and create a greater EPOC effect, in which blood oxygen levels are higher.

One of the important aspects of hypertrophy is also achieved with the Rest-Pause technique:

• You increase the time under tension, and metabolic stress is higher; this promotes sarcomeric hypertrophy because, through phosphocreatine recovery, you can engage more power fibers.
• On the other hand, metabolic stress will also cause significant muscle congestion, which helps you create sarcoplasmic hypertrophy.

Rest-Pause during a cutting phase

During a cutting phase, you will follow a hypocaloric diet with a negative energy balance, but it is also useful to recruit power fibers. Why?

For those fibers to be maintained, not to grow, because if the diet is hypocaloric, you will not achieve significant sarcomeric hypertrophy.

In any case, you will always achieve sarcoplasmic hypertrophy; it is nonfunctional sarcoplasmic hypertrophy that always occurs when you train, whether hypercalorically or hypocalorically.

In the case of a hypocaloric diet, a bodybuilder loads up on a drink containing a large amount of carbohydrates—in other words, an intra-workout drink with cyclodextrin and amylopectin.

When you start training, you start drinking, because of course, practically that insulin spike created at that moment, along with that temporary excess glycogen, will fill your muscles, and that will happen with both a hypercaloric and a hypocaloric diet.

But in cutting diets, it is very important to train using the Rest-Pause method, since even with less energy overall, it will help you recruit that type of internal muscle fiber, which at that point in the diet will be key to maintaining muscle mass.

The 1st critical point: “carbohydrates”

During a cutting phase, the Rest-Pause technique may even be more beneficial, because when you start reducing calories, you also begin reducing the three macronutrients, including carbohydrates, which are the ones that regenerate ATP most quickly.

If you do not have enough carbohydrates, of course, your ATP levels will be lower, so maintaining tension for 20, 30, or 40 seconds will be more difficult,

When you do not have that carbohydrate supply, it will be more difficult to reach those type II fibers, those power fibers, the white fibers.

From this point of view, maintaining short rest periods after momentary failure will help you recruit those power fibers and therefore keep them working “during that calorie-restricted period.”

The 2nd critical point: “training very heavy”

This is one of the keys when we are cutting;

• It does not create muscle mass, but it does maintain the power fibers, especially when we are talking about type II A-B fibers, and some even refer to type X or C.
• We are talking about the inner fibers, those maximum-output fibers that are recruited with a very heavy weight, close to 100% of your 1RM.

This could lead to an injury, so the solution would be to work at 60, 70, or 80% of your 1RM with short Rest-Pause sets, which would help you recruit those inner muscle fibers equivalent to working with a weight close to 100% of your 1RM.

For Raúl Carrasco, our IFBB Pro, the Rest-Pause technique is not better than training with an extremely heavy weight, as it provides the same benefit when it comes to creating hypertrophy, but with a lower risk of injury.

Is the Rest-Pause technique perhaps a more beneficial system than doing Heavy Duty with a forced-repetition system, having your training partner help you from behind?

Well, Raúl answers this question in the video you have just watched, which we have summarized in a few words:

• It is not better; it is the same, but always with a lower risk of injury.
• Perhaps the Rest-Pause technique creates more metabolic stress than a set taken to complete failure with two forced repetitions.
• When it comes to creating sarcomeric hypertrophy, it is still a high-intensity technique that was even used in Heavy Duty.

In short, it works at high intensity, both during bulking with a hypercaloric diet and during cutting with a hypocaloric diet.

The effectiveness of Rest-Pause

We analyzed a study published in the Journal of Strength and Conditioning Research in 2019 that measured muscle and strength adaptations in the thighs

The markers compared between Rest-Pause and traditional training were muscular strength, hypertrophy, localized muscular endurance, and body composition.

The bodybuilders in question were randomly assigned to:

• One traditional multiple-set training group (n=9; 7 men and 2 women) performed 3 sets of 6 repetitions at 80% of 1RM, with 2-minute rest intervals between sets.
• One group performed Rest-Pause (n=9; 7 men and 2 women). .

Although the results showed no significant differences (p> 0.05) between the groups in 1RM strength (16 ± 11% for the bench press, 25 ± 17% for the leg press, and 16 ± 10% for the biceps curl in the Rest-Pause group vs traditional multiple sets: 10 ± 21% for the bench press, 30 ± 20% for the leg press, and 21 ± 20% for the biceps curl).

For localized muscular endurance, the group that trained using the Rest-Pause technique performed significantly more repetitions (p <0.05), only in the leg press exercise (mini-rest training: 27 ± 8% vs traditional multiple sets: 8 ± 2%).

For muscle hypertrophy, the group that trained using the Rest-Pause technique showed significantly greater thickness (p <0.05), only in the thigh (mini-rest training: 11 ± 14% vs traditional multiple sets: 1 ± 7%).

According to this landmark study, the Rest-Pause technique resulted in similar gains in muscular strength to traditional multiple-set training; however, it resulted in greater gains in localized muscular endurance and thigh muscle hypertrophy.