March 13, 2017

The repetition bible

Here's what you need to know...

How you perform your reps plays a big part in stimulating the gains you want to make.
The principle underlying CAT is that if you move a submaximal weight, you can compensate for this lack of resistance by accelerating faster.
Dynamic correspondence repetitions require that you should move the weight in the same way as a maximal weight - same speed, same acceleration and same tension.
Repetitions with constant tension are based on the principle of occlusion, which is based on limiting the blood supply to the muscles and the resulting oxygen deprivation.
Normal repetitions allow you to have enough energy to perform more repetitions with a given weight while still using enough force to stimulate muscle growth and strength gains.

How should I perform my repetitions?

I never get asked this question. That's a shame, because how you perform your reps plays a big part in stimulating the gains you want.

Think about it: the training session itself is nothing but a long set of repetitions spread over different exercises. The basic unit of your training session is the repetition. The more repetitions you perform correctly, the better your gains will be.

By performing correctly, I mean performing the repetition in the right way to achieve the exact stimulation necessary to get the gains you want.

There is more than one correct way to perform repetitions and the different execution styles depend on what your goals are.

The 4 repetition styles

1 - The CAT repetition

The concept of Compensatory Acceleration Training - CAT for short, meaning compensatory acceleration training - was popularized by powerlifting legend Fred Hatfield. The basic premise is simple:

Strength equals mass times acceleration.

In other words, you can increase the amount of force your muscles need to produce by increasing the mass (the weight on the bar) and/or the acceleration you exert on the barbell as you move it upwards.

The principle behind CAT is that if you are moving a submaximal weight, you can compensate for the lack of resistance by accelerating the weight faster.

What does such a repetition look like? Let's say you are training bench press. A CAT repetition means that you move the weight explosively upwards from your chest and try to accelerate the bar as much and as long as possible.

Another aspect of CAT is the transition between the eccentric (lowering) and concentric (lifting) part of the movement. The transition itself should be fast. This requires very strong antagonistic muscles to stabilize the joints at the point of change in direction of movement. For example, you need strong rhomboids, strong posterior shoulder muscles and a strong latissimus to be able to perform the quick change of direction of movement in the bench press. Even the biceps can help here.

Most of the eccentric phase should be performed under complete control (not slow, but you must control the barbell), but the movement at the reversal point of the movement must be fast and then you must try to produce as much acceleration as possible as you move the weight up.

If the weight is heavy, the bar may not move really fast. The acceleration is meant to compensate for a lighter weight and a heavy weight means you won't be able to compensate much and the acceleration won't be strong. Regardless of this, you should still try to achieve as much acceleration/speed as possible.

Advantages of CAT

This style of repetition maximizes maximum force production at any given weight, making the muscles stronger.
By working on acceleration, you will also develop more power/explosiveness than if you use a more 'regular' repetition style, which is good if you are an athlete trying to be explosive.
By trying to move the weight as fast as possible, you maximize the recruitment of the fast-contracting motor units. Over time, you will become more efficient at recruiting these fibers, which will obviously help you develop more strength, power and muscle mass in the future.
By using the stretch reflex at the reversal point of movement, you will become more efficient at using it in muscle actions, which can help you in sports activities that require the use of this stretch reflex.

Disadvantages of CAT

It will sound strange since I mentioned that CAT maximizes the maximum force release during a repetition with a given weight, but CAT is not optimal when it comes to developing 1RM strength with slow movement speed.

You'll get stronger on fast reps, but once the weight gets too heavy to accelerate, you won't be able to push it up any further. Someone who trains in a different way will usually be able to slowly push a weight up with maximum effort that is much heavier than the weight they can move with acceleration.

I also mentioned that CAT leads to a higher maximum force production for a given weight. This is also true so far. But it does not mean that the average force production over the entire range of motion is higher. In fact, this is not the case.

What happens is that you produce a very high maximum force at the beginning of the movement, but have quite low levels of force production in the later parts of the movement because you are relying on the momentum produced by the initial push.

In reality, momentum actually reduces the mass you need to overcome in the later parts of the movement, which reduces the amount of force you need to produce.

What happens is that you become very good at producing a burst of force over a very short period of time/movement space, but lose the capacity to sustain that force production for the duration of a repetition.

This means that you will not be able to 'choke' heavy weights slowly upwards. When the momentum from the initial push comes to an end, so does the movement.

This is why we sometimes use bands and chains, these tools adjust the resistance in the upper range of motion. They can counteract the effect of the initial momentum generated and allow you to maintain a higher force production throughout the range of motion.

Unfortunately, bands cannot be used for very long. They drastically increase the eccentric load during exercise execution, which significantly prolongs the recovery phase. You should not use bands for more than three weeks in a row. Chains are more forgiving and can therefore be used more frequently.

When you should use CAT

CAT should only be used for the heavy basic exercises - and especially for exercises of a pressing nature such as bench presses, shoulder presses, push presses (standing shoulder presses with some momentum from the legs), squats and front squats.

CAT does not work so well with deadlifts because you lose your position during the first pull (from the floor to the knees), which is both inefficient and dangerous. Deadlifts are better performed with a gradual acceleration.

CAT is also not ideal for pulling exercises such as pull-ups and rowing, as much of the workload is shifted away from the back to the biceps and forearms.

CAT should only be used if you have a solid and correct technique for the exercise you want to use it for. Using CAT on exercises where your technique is not solid and stable will often result in poor exercise execution form, or at least form that is not the same as your heavy exercise executions.

Even though CAT is a method that builds power and explosiveness, ironically, athletes who are already very explosive should not use this technique too often. The more explosive you are, the lower the average power produced throughout the range of motion, as a person who is super explosive can generate tremendous momentum on the first push.

CAT is therefore best used in heavy multi-joint exercises by exercisers who are not naturally explosive and who have good exercise execution technique.

2 - Dynamic Correspondence Training

The basic premise of dynamic correspondence training is that every exercise should look exactly like a maximal effort exercise. This means that if you want to get good at developing maximal strength on a maximal attempt, you should get as much practice as possible under the same conditions.

A lot of people have excellent technique at weights up to 90-92% of their max - the tempo is good, the execution looks solid and the technique doesn't let up at any point in the movement. But when these people get into the 95 to 100% zone, everything goes down the drain.

Technique is neglected and ultimately the weight on the max attempt isn't much higher (if it's higher at all) than the 3RM weight (the max weight for 3 reps).

I already addressed this issue to some extent when I talked about the disadvantages of compensatory acceleration training (CAT): You get good at demonstrating strength under a certain type of contraction or circumstance, but if the weight forces you to use a different strategy of force production, then you lose all your efficiency.

So the underlying principle of dynamic correspondence training is to strive to make each repetition in a heavy multi-joint exercise look exactly like a repetition with maximum effort would look. This means lowering and moving the weight up in the same way as you would at your maximum weights - same speed, same acceleration, same tension.

When performing CAT reps, you compensate for the lack of weight by accelerating harder, but in the dynamic correspondence approach, you compensate for the lack of weight by contracting the muscles involved in the movement harder - in a sense, as if you were trying to tense the muscles as hard as possible during the movement.

This action could also be called compensatory tension, as you compensate for the lower weight by increasing voluntary muscle tension.

Advantages of dynamic correspondence

Dynamic correspondence training makes you efficient at overcoming resistance and conditions like a maximal attempt. This means that your form will most likely be much more stable when using maximum weights and should allow you to reach higher maximum weights and reach them safely.
Dynamic correspondence training also teaches you to recruit your muscles more efficiently and makes the joints involved in the movement more stable.
This capacity to recruit muscles more efficiently will eventually become automatic and you will be

become more stable when performing heavy basic exercises
stimulate your muscles more because you are more efficient at recruiting these muscles

You will also become more aware of your body position during these types of repetitions, which will make it easier for you to learn and perfect correct technique

Disadvantages of dynamic correspondence

The biggest disadvantage of dynamic correspondence training is that if you only perform this type of training, you will lose your capacity to produce force during high speed/explosive actions.

If you perform these repetitions correctly (producing maximum tension by consciously tensing your muscles as hard as possible), then you will make each repetition significantly more demanding and this will significantly reduce the number of repetitions you can perform. Fatigue will set in much faster than with normal repetitions. For this reason, it is better to use dynamic correspondence on sets with low repetitions - say 1 to 3.

You can use dynamic correspondence for up to 5 repetitions, but it may well be that the tension is not as strong on the last two repetitions. This is perfectly fine because fatigue "makes the weight heavier" (relatively speaking), so reps 4 and 5 will actually feel like max reps even though you're not using as much tension.

Some people simply perform "slower reps" that mimic the speed of a max repetition without contracting their muscles as hard as possible. If you do this, then you will probably actually lose strength as your force release will be low. If you are performing a dynamic correspondence repetition, then a repetition should look and feel like a max repetition. You are simply making a lighter weight as demanding as a max weight.

When to use dynamic correspondence

It's best to use dynamic correspondence when you're focusing on max strength while using a progressive loading cycle (like my 915 plan), where you start a training cycle with a moderate weight and low reps and gradually increase the weight until you're moving a max weight 8 to 12 weeks later.

In this case, the main exercises - the exercises where you want to test your strength at the end of the cycle - will be performed using dynamic correspondence, while supportive training will be done using CAT or normal repetitions.

Dynamic correspondence training is also a good way to perform your repetitions if you like high-frequency training. For example, if you choose to bench press and deadlift five times a week, it's best to use a lighter weight and keep the reps low.

With such an approach, you typically stay in the 75 to 80% range most of the time (with an occasional day at 90 to 95% to see where you are) and perform 3 to 5 repetitions or even fewer repetitions.

The dynamic correspondence method is very well adapted to this type of training because it aims to develop strength skill: The ability to show strength under conditions of maximum effort.

3 - Training with constant tension

Constant tension repetitions are based on the principle of occlusion, which is based on the fact that when the blood supply to the muscle is restricted, the muscle is deprived of oxygen.

This lack of oxygen, as well as the inability to remove the waste products that accumulate during muscle contractions, increases the release of local growth factors, which can trigger hypertrophy or muscle growth.

Occlusion can be achieved through the use of cuffs that restrict blood flow to the exercised limb, but constant tension can also achieve this.

When a muscle contracts, the blood flow into the muscle is stopped or at least greatly reduced. Only when the muscle relaxes again can blood flow into the muscle. The harder a muscle contracts, the less blood can flow into the muscle.

So if the target muscle remains contracted throughout the set and never relaxes, you can achieve a type of occlusion. To do this, it is crucial that you contract the target muscle as hard as possible during every inch of the movement. You must not stop the contraction until the movement is over.

Imagine that you are not moving a weight, but simply contracting the muscle. Each phase of the repetition is performed slowly to maximize both the time under tension and the amount of tension. If you perform the movement too quickly, the momentum will result in short periods of relaxation, which will destroy the effect of the occlusion.

Advantages of constant tension

This repetition style works well to isolate a muscle group and stimulate local hypertrophy. It does this via a local release of growth factors rather than muscle damage or heavy mechanical work. You don't need to use a heavy weight, as studies have shown significant gains with this type of contraction using as little as 30% of maximum weight.
Training with constant tension can be done very frequently and will not negatively affect subsequent training sessions.
This style of training will improve the mind-muscle connection with the target muscle, which means you will be better at recruiting muscle fibers in the future.
Constant tension training is also very safe due to the slow movement performed with a high degree of tension.

Disadvantages of constant tension

This type of training will not build strength. And if you only train this way, you will have bigger muscles, but you will be weak. Constant tension training is a great way to learn to use a specific muscle, but can mess up the mechanics of a heavy basic exercise.

Constant tension training also requires a lot of mental focus and significant pain tolerance, as you will achieve a lot of muscle burn during the set with these types of repetitions. Muscle burning is an indicator of a strong accumulation of metabolic waste products, which can stimulate the release of growth factors.

You will rarely be limited by your strength with this method. Instead, the limit will be based on how much muscle burning you can tolerate. Over time, this type of training can become very mentally demanding.

Constant tension does not work well with multi-joint exercises. It is best suited for isolation training and should never be the foundation of your training. So even though this method is effective, its applications are limited for someone who prefers to focus on the big basic exercises.

When you should use constant tension

Constant tension is best for isolation exercises. I prefer to do almost all of my isolation training this way. I do a lot of heavy training with the big multi-joint exercises, which helps me develop strength and explosiveness, so using constant tension in isolation exercises gives me what I don't get from my main exercises.

I also like constant tension training because it teaches me to use those muscles. For this reason, I use it for my weakest muscles - not only to build them up, but also to get better at recruiting those muscles, which allows me to use them better in my heavy core exercises as well.

The only time I use constant tension with clients in multi-joint exercises are exercises that are performed with only your own body weight, such as push-ups, dips, squats without additional weight, etc. In these exercises, the external load is quite light and I only use constant tension here if the client can perform at least 15 repetitions of the exercise in question.

4 - "Normal" repetitions

By normal repetitions I mean repetitions where

No specific effort is made to perform them as explosively as possible
No specific effort is made to generate as much tension as possible
Not attempting to contract the target muscle through every inch of the movement
Not attempting to perform each repetition with minimal effort/accumulating exhaustion

This does not mean performing sloppy repetitions or repetitions without concentration. It means lowering the weight slowly and under control and then moving solidly back up, dominating the weight without accelerating it excessively.

The weight is controlled, not slowly lowered, and controlled in such a way that you could easily pause at any point in the range of motion.

Normal repetitions are also characterized by a rapid but smooth transition from the eccentric to the concentric part of the movement. In contrast to the "perfect repetition/CAT", you do not try to execute this transition as quickly as possible and perform an explosive concentric repetition using the stretch reflex. Instead, you reverse the direction of movement of the weight in a controlled manner and when you transition to the concentric part of the repetition, it is a smooth push/pull.

You perform the concentric part of the movement by producing enough force to overcome the weight solidly, but without accelerating it as much as possible. The goal is to perform each repetition with power and using perfect technique without burning yourself out.

At the highest point of the movement, take the time to hold the weight for a second before moving on to the next repetition.

Advantages of normal repetitions

Normal reps are the happy medium between CAT/dynamic correspondence (where you make the reps more demanding by producing more force than necessary) and reps performed with the least amount of fatigue possible, as is the case with kettlebell swings on volume or crossfit WODs.
They allow you to have enough energy to perform more repetitions with a given weight while still using enough force to stimulate muscle growth and strength gains.

Disadvantages of normal repetitions

While normal repetitions are good for muscle hypertrophy because they allow you to perform more repetitions with a given weight, they are not optimal for building strength unless you are using a heavy weight.

You can build strength with CAT and dynamic correspondence if you use 70% of your 1RM weight because you are "artificially" increasing strength production. This will not work with normal repetitions.

When you should use normal repetitions

It's best to use normal reps when you're using a moderate weight for a moderately high amount of reps - sets of at least 6 and up to 15-20 reps, at least for multi-joint exercises.

Normal reps are also the way to perform isolation training with low reps/on strength. We don't often perform isolation exercises on strength, but it is possible if the goal is to make a single muscle stronger rather than bigger.

In this case, normal repetitions are the best option. Constant tension will not allow us to use enough weight and CAT will make most exercises worthless as momentum will do most of the work for you.

Are there other repetition styles?

Countless! Other repetition styles exist for more specific applications, but 90% of the time the ones described here are the ones you should use. Master these and you'll never complain about your gains again.

by Christian Thibaudeau | 03/03/15

Source: https://www.t-nation.com/training/rep-bible