I switched my routine from full-body to split: the result is worse than I expected

Question

I have been going to the gym for 2 years and 3 months now. My primary goal is to build muscle.

I have to admit that in the first 2 years, I only used machines. Sometimes I used dumbbells, but no barbells at all. I went to the gym up to 4 times a week, up to 90 minutes each. I used full-body routine back then: up to 8 different workouts with 4 sets x 8 reps. I noticed that I was getting stronger each day and I built some muscles.

After those 2 years, I thought I should level-up myself, from beginner to intermediate level. I read articles from the internet and I thought it'd be better for me to switch my routine to split. So for the last 3 months, I go to the gym 3 times a week. The days are splitted into: triceps+chest, biceps+back, and shoulders+legs. Each consists of 7 different workouts with 4 sets x 12 reps. This is also my first time to incorporate barbells. Yep, I just learnt how to bench-press last 3 months.

But this hits me hard. I feel weaker day-by-day. At first I thought it's because the workouts are different from the usual and more stress out specific part of the body. But I didn't notice any improvement on my muscle size either. The fat% however is somehow also increasing. Now I feel a bit unmotivated...

So, what is actually going on here? Did I make any mistake or miss something? Should I change back to my old full-body routine (if this is the case, I might improve the regimen by incorporating the barbell tho)? As the fat% increase, did I unintentionally change my diet to unhealthier one?

Answer 1

In order to get stronger you should generally train each muscle 2 or 3 times a week with at least one day of rest in between. There are some exceptions to this guideline. For instance the deadlift can be trained once a week. However it is a good general guideline, and I believe it is where you are going wrong in your training.

So if you want to do your 3 way split you should train 6 days a week. I found an example of the 3 way push/pull split you are using. Here they clearly state: train 3 consecutive days, rest one day, repeat. A little less (5.25 actually) than the 6 days I estimated above, but a lot more than the 3 days you are currently doing. Instead you may do a two way split. Either a 4 day push/pull split or a 4 day lower/upper split.

Personally I find 4 times a week too much so I prefer a full body program 3 (or sometimes 2) times a week. Currently I am following the Phrakture Greyskull variation:

BTW I can recommend the book "The new rules of lifting" by Schuler and Cosgrove. It explains the principles behind getting stronger in a simple manner. It also explains how you can substitute other exercises for the exercises in say the program above. As an example the bench press is a horizontal push. Instead you may choose another horizontal push such as (weighted) push-ups (and I do).

Answer 2

I noticed that I was getting stronger each day and I built some muscles. [...] After those 2 years, I thought I should level-up myself, from beginner to intermediate level. [...] Yep, I just learnt how to bench-press last 3 months.

I think part of the problem here is that you prematurely levelled yourself up. For starters, if you've just moved from machines to barbells, you should give that some time. There are some new muscles your body will make you aware of. Secondly, there are a lot of ways in which people define beginner, intermediate, and advanced weightlifters but I think this is the best definition:

Beginner: Responds to linear progression.

Intermediate: No longer responds to linear progression, needs to implement short term periodization.

Advanced: Needs to implement long term periodization.

Excerpt from this Reddit post.

I was trying to find a video of Jeff Nippards where he says his favourite definition of the three; I can't find it though. It was something along the lines of beginners make weekly strength gains, intermediate lifters make monthly strength gains, and advanced lifters make yearly strength gains.

"Intermediate" programs that are on the internet are usually 'splits' that follow the "beginner" full-body workouts. As @Andy mentioned, you've gone from working each muscle four times a week, to once per week. The reason you would use a training split is if your muscles no longer had enough recovery time in-between workouts. This is not your case and so they are getting more rest than you need and you're missing your supercompensation. Rest days are important but if you space them out too much you end up under-training.

Answer 3

You experience the most growth when you start working out because your body is not used to it. In a way, you experience the most “difference” during that time. You can become stronger not only through hypertrophy but also neural adaptations (https://www.scientificamerican.com/article/how-does-exercise-make-yo/).

As you workout for a longer period of time doing the same routine, your growth slows, and you will hear numerous advices asking you to switch things up. Challenge your body and they will adapt and become stronger!

I believe the main benefits of full body routine is efficiency and being able to hit a greater total volume for a given muscle.

This is a great article to learn and understand how muscle hypertrophy works!

https://medium.com/@SandCResearch/explaining-how-hypertrophy-works-using-only-basic-principles-of-muscle-physiology-48beda5fbf1b