I've been seeing a few posts on here about people's training schedules and a lot of 'single body part days', but I haven't seen a lot of 2-3x per week programs/regimens, so I figured I would make a post about it on here. This isn’t to say 1x a week isn’t good, at the end of the day it is all about the individual. This is just some free chicken for the mind.

A study in 2017 Yue et al (1) compared two volume equates programs (one group was High Volume - Low Frequency, HV-LF, who trained two days a week, and the other was Low Volume-High Frequency, who trained four times a week). The data revealed little to no difference in measures of strength or body composition between the two and four-week group, however the HV-LF group gained more muscle in their upper body and an overall improved muscle composition. Compare this to a meta-analysis from Schoenfeld, Ogborn and Krieger published in 2016 (2) that illustrated two times per week training to be superior to a single session. It can be inferred that once a week is not enough, and that four or more training sessions per week is too much.

But why?

1. Muscle Protein Synthesis: The MPS process is, at the lowest explainable level, the period in which your muscle is it's hungriest for nutrients. It is spiked at about 24-48 hours, and returns to baseline shortly thereafter. There are a lot of discrepancies and opposing studies that show anywhere from as short as 24 hours or as long as 72, but the MPS process has a very large individual variance and essentially any differing research inside of the 'accepted' 48 hour window is just splitting hairs. (3)(4).

As you have probably figured out by now in your training, the more you work a muscle, the more sore it is. That is because there is a max to how much stimulation a muscle can receive in a session. Beyond that, we hit the law of diminishing returns. Every time you train a muscle, you are essentially "opening the doors for the muscle into MPS." So knowing that it is elevated for around 48 hours, wouldn't it make sense to try to hit each muscle around that time?

Picture this: You fucking love roller coasters, but you get bored of things easily. You buy a season pass for an amusement park with 6 rides. A, B , C, D, E, and F but there are stipulations. Every time you go, you can only do 4 rides total, and you will lose interest in those rides for the next 2-3 days. So you go on monday and ride Roller Coaster A, your favorite ride there, 4 times. Then Tuesday you go back, but you're like "fuck roller coaster A, im gonna ride B all day." Fast forward to Thursday. You go back and say "I kind of want to ride A again today because it is my favorite, but im going to do Roller Coaster D today, and then I'll wait until Monday to hit A again.

Seems dumb right? Why not ride A/E 2 times each monday, then B/C Tuesday, then D/F Wednesday, then A/C Thursday, and B/E Friday, and D/F Saturday? Hit both rides twice a week and spaced out enough.

Now, replace A with Chest, B with Back, C with Legs, D with Shoulders, E with Triceps, and F with Biceps.

See where I am going with that?

Adding more frequency allows repeated elevations in MPS, and time spent in a positive net protein balance.

By training with enough volume to stimulate the muscle, but not overtrain, your recovery time is quicker which will allow you to train it more frequently throughout the week.

2. Adaptation: The human body is an adaptation machine. We adapt to everything. it is why in 200 years we will probably not have pinky toes. No need for them.

How else do we adapt? Exercise. The changes that come from your training aren't like pouring water in to a bucket. It is not "If I pour 1 gallon of water in a 2 gallon bucket, I will have 1 gallon of water in the bucket". It is more like pouring water into a hole of sand. If you pour 1 gallon in, the water will absorb in to the sand and you will end up with maybe 1/8th of a gallon of water. If you let that sit for a few hours, it will go down. If you pour more water in shortly after, it will fill up a little bit more since there is less room for water to be absorbed into the sand in the side at the bottom, but still some at the top where the first pour didn't reach. Not the greatest example, but the point I am trying to make is it is not an equal/opposite reaction.

Anyways...

Going along with MPS, muscles grow and change from stimuli. Step on a nail, your skin regenerates over it, but just a little bit harder. Step on a nail in the same spot, the skin comes back harder.

If you train with the schedule of 'body parts once a week', your body will adapt as if "I only need to be strong with this muscle once a week. It does not need to be super resilient the rest of the week, but one day a week, it will need to be strong." This is like moving a refrigerator across your house once a week. Super hard once, and then easy the rest of the week.

Train it twice a week, and that tells your body "fuck I need to get stronger. I need to build more muscle mass to be able to do this. Instead of moving this refrigerator 200 feet once. I will have to move it 100 feet twice. Or 66 feet 3 times.

3. Phasing: Going along with this adaptation process, this not only includes the frequency, but also the intensity and volume. Eventually, your body will adapt to the training you throw at it. It won't need to get stronger or faster because it is always the same. It will get really good at doing your current split. This is where phasing your programs come in to play.

Maintaining the frequency, you can change up the intensity and volume inversely (when volume is high, intensity should be low, and vice versa). Always go between strength phases and hypertrophy phases. I normally do 4 week strength phases and 6-8 week hypertrophy phases, just because heavier weights are more taxing on the body and joints.

"But Andrew, isn't going back and forth going to cause the same adaptation that would happen anyways?"

No, dumby. Do a 4 week strength phase. When you go into that hypertrophy phase, you will be stronger (no shit) and the 8-12 reps you do will be at higher what they were before, and you will continue to grow and adapt to the changing weight and intensities. Though you aren't doing heavier weights, you are still getting stronger (diet dependent, of course). Now go back in to a strength phase after a few weeks. If you were continuously getting stronger on your hypertrophy based lifts, where do you think your strength/heavy lifts will be at when you go back to that phase???

Let's hear some thoughts, feedback, and get some conversation going on this.

References below:

(1) https://www.ncbi.nlm.nih.gov/pubmed/29216446

(2) https://www.ncbi.nlm.nih.gov/pubmed/27102172

(3) https://www.ncbi.nlm.nih.gov/pubmed/8563679

(4) https://www.ncbi.nlm.nih.gov/pubmed/8563679