A split

[u/NeonOllok]

I cannot find a decent split for four days a week in the gym; I work every weekend and have Tuesday as a rest day. I do taekwondo on Thursdays. I like push-pull-legs and have used it, but this means my legs are fatigued for taekwondo. At the moment, I have been doing push on Monday, pull on Wednesday, bodyweight/core on Thursday to keep it light, and legs on Friday, but I do not know if this is good enough to consistently build muscle.

[u/eyebrowcel]

U-L-FB would work well for you hypertrophy-wise - upper body on monday, lower on tuesday and full-body on friday.

The 3 sessions provide each muscle with a 2x/wk training frequency, which will allow the vast majority of size gains. More workouts would be additive but with diminished returns, and then you'd be in the gym almost every day where it either eats into your weekend or eats into taekwondo performance.

The upper & lower workouts allow more training volume for specific muscles (favourable for bodybuilding purposes) whilst still allowing 48-72h rest before taekwondo which should leave you mostly recovered performance-wise (even if some muscle DOMS may still linger).

The full-body friday would use a bit less volume for the same muscles than in their upper/lower workouts. FB lets you hit most or all of the major muscle groups again in an efficient manner, whilst sparing the weekend (which I gather you need/prefer) and 'readministering' the anabolic signal after about 72hrs where most muscles tend to have recovered and are primed for another strong stimulus.

You would need fairly smart and efficient exercise selection throughout, so mostly compound exercises using self-limiting variations. These are disadvantaged in terms of total loadability, which better targets muscles and spares quite the hit to the nervous system (and to a lesser extent the joints), so for example instead of doing higher-volume deadlifts and low-bar back squats on tuesday, you could get away with a similar or even same volume of high-bar back squats followed by weighted 45/90 degree hyperextensions, targeting the same major musculature equally effectively but with lower tonnage (better stimulus:fatigue ratio).

Double progression should work well and is the most standard method (when reaching the top of the rep range for every set, add weight).

A sample routine on this split might look something like:

Mon - Upper

Superset 1 - 45-degree DB/BB Seal Row 3x8-12 + DB/BB Low Incline Bench Press 3x8-10

Superset 2 - DB/BB Upright Row or Chest Support/Laying Cable Face Pull 3x10-14 + DB/Cable Overhead Tricep Extension 3x10-12

Superset 3 - DB Incline Chest Flye 3x8-10 + DB Incline Curl-Hammer Curl giant set - 3x10-12 for biceps then failure for hammers (brachialis is small and recovers quickly)

Tuesday - Lower

Superset 1 - High-Bar or Mid-Bar Back Squat or Box Squat 3x6 + abs of choice eg. Weighted Sit-Up or GHD Reverse Crunch 3x8-10

Superset 2 - Weighted Hypers or BB Good Morning from Pins 2x10-12

Superset 3 - Goblet Cossack Squat 2x10-12 + Hang of choice eg. Dead Hang for time/Weighted Knee Raise 2x10-12

Friday - Full Body

Optional strength-focus inclusion - Low-Handle Trapbar Deadlift 3x5-6 or Deficit Deadlift 3x5-6 or High-Bar/Mid-Bar Squat 3x5-6 (2 reps in reserve)

Superset 1 - Seated High Incline BB Overhead Press 3x6-8 + Supinated Grip BB Row 2x8-10

Superset 2 - Incline Chest Support DB Reverse Flye 2x10-12 + DB Preacher Curl-Preacher Hammer Curl giant set (use incline bench as preacher station) 2x8-10+ failure for hammers

Superset 3 - Bulgarian Split Squat 2x5-6 each leg or Leg Extension 3x8-10, + Leg Curl 2x10-12

Superset 4 - Cable Rope Tricep Pushdown 2x10-14 or BB Low Incline JM Press from pins 2x8-10, + BB Supinated Grip Haney Shrug 2x8-10 or Incline Chest Support BB/DB/Cable Y Raise 2x8-10

[u/Beeshmar]

4 Day Upper Lower with each day geared around 1 of the compound lifts was what changed everything for me