CAT on Every Rep?

[LoRez]

Are there any caveats for using CAT for all reps, always?

For my main strength work, I’ve been experimenting with using velocity training. From what I understand, mean concentric velocity is only meaningful if you’re attempting to maximize force through the whole rep, e.g., CAT reps. (I’m using velocity for step-loading; reach a target velocity, add weight, repeat.)

When I first made the shift from “normal” reps to CAT reps, I did notice they took a lot more out of me. Now that I’m on the other side of that, I’m wondering what the downsides are. I have found a lot of support for “CAT reps, always” (direct/indirect readings of Fred Hatfield, Sam Byrd, Josh Bryant) but not a lot of counter-support.

Just wondering if you have any experience around this.

[Christian_Thibaudeau]

Well it depends on what you are trying to accomplish.

For strength development I do believe that you should always try to push as hard as you can during the concentric, attempting to create acceleration. Studies are quite clear that you gain more strength if you try to lift a weight with the most acceleration that you can.

However, if your goal is hypertrophy, the use of CAT is debatable and likely less effective. The reason is that the faster the barbell goes, the less tension there is on the muscle. And tension is the main driver of hypertrophy.

YES by doing explosive reps you are recruiting more fast-twitch fibers, but you are placing a lot less tension on the muscle, so it leads to less growth stimulation. Take jumps and throws for example, they are super explosive, thus recruit mostly fast-twitch fibers, but will not build muscle, even at a high volume of work.

Now, arguably, if you train to failure or close to it (1 RIR for example), even if you try to accelerate, the bar speed will be slow and at that point the reps become effective.

But then it becomes an issue ot demands. As you noticed yourself, doing reps with CAT as opposed to the “proper effort for the proper difficulty” is a lot more demanding. If you do hypertrophy work, which is arguably higher in volume, it could lead to more central fatigue during the workout which dramatically reduces the effectiveness of the sets.

Again, look at what the most successful people are doing. There aren’t a lot of very muscular guys trying to create maximum acceleration on all the reps (maybe Branch Warren). Most use a piston-like speed. And those who try to accelerate all reps (for hypertrophy work) are also often those who are injured the most. An exception is Danny Padilla (for old-school bodybuilding lovers). But these guys are the exception, not the norm.

Personally for strength I recommend trying to accelerate the weight as much as possible, regardless of the weight (if it’s light it will move fast, if it’s heavy it won’t). But fo hypertrophy I rarely recommend that.