Most gym-goers have been caught in the cycle of training 1-2 muscle groups per day, week in week out. Such was touted for so long as the best approach: Legs on Monday, Back on Tuesday, etc. But as the scientific literature evolves, we're learning that full-body workouts may accelerate your results.

This old school "1-2 muscle groups per day" was popular because people didn't want to "overtrain." The rookie gym goer likely believes they need the time to recover.

But science says otherwise.

Research shows that muscle protein synthesis (the process of your body repairing a muscle group after you've trained) returns to normal after 48 hours (1). What this means is that after two days, you're free to train that muscle group again!

With the old school method of training, you're letting 5 days pass you by where you can train that muscle again. Over a year, that's a substantial loss of potential muscle size and strength!

The science is enough to change your routines as fast as possible.

How many times should I train each muscle group per week?

One study compared a group who trained each muscle group once per week to another who trained with the same amount of volume, but over 3 days (2).

The researchers found the one muscle group per week subjects experienced just 62% of the strength gains of the 3 times per week group.

So if you're aiming to improve your chest strength, the below workout:

bench press

Tuesday (chest day)

- 5 x bench press

- 5 x incline dumbbell press

- 5 x cable flies

Could be replaced with the following:

Monday: 5 x bench press

Wednesday: 5 x incline dumbbell press

Friday: 5 x cable flies

It's the same amount of exercises, but carried out when you're fresher, thus likely to gain more strength and size.

And given that working at 90% of your 1 rep max (the amount of weight you can lift only once) has been found to elicit greater muscle gains than training at 70% of your 1 rep max (3), it stands to reason that getting stronger continuously should be your goal, hence the chest workout spread out over three days and not one.

Further research declared: "...frequencies of training twice a week promote superior hypertrophic outcomes to once a week. It can therefore be inferred that the major muscle groups should be trained at least twice a week to maximize muscle growth" (4).

Ok, so we know we need to train our muscles more often, but what would a full-body program like this look like?

Full Body Workout Splits: Gain muscle and strength faster

deadlift

Your new program might look something like this: 

Monday:

5 x squats (quads)

5 x Bench press (chest)

5 x lat pull down (Back)

5 x hamstring curl (hamstrings)

Tuesday:

5 x seated military dumbbell press (shoulders)

5 x cable push downs (triceps)

5 x hip thrusts (glutes)

5 x standing bicep curl (biceps)

Wednesday: 

5 x leg press (legs)

5 x cable flies (chest)

5 x hammer strength rows (back)

5 x seated hamstring curls (hamstrings)

Thursday: REST

Friday:

5 x lunges (legs + glutes)

5 x Incline dumbbell press (chest)

5 x cable rows (back)

5 x Nordic Hamstring curls (hamstrings)

Saturday (A big day, but given you might be prone to overeating on Saturday's, there's no harm! Drop the standing dumbbell curls for biceps if you feel it's too much).

5 x seated military press (shoulders)

7 x skull crushers (triceps)

5 x bent-over rear-delt raise (rear delts)

5 x seated glute machine (glutes)

5 x standing dumbbell curls (biceps)

Sunday: REST.

This enables you to hit muscle groups 10-20 sets per week, which we know is the touted correct amount of sets for muscle growth (5).

Moreover, given we're spreading them out, we know we'll be fresher and have more energy and thus strength to make these sets count (2).

So, for superior results in 2021, be sure to give full-body workouts a try.

Science declares you'll see the difference! 

References

(1) Phillips SM, Tipton KD, Aarsland A, et al. Mixed muscle protein synthesis and breakdown after resistance exercise in humans. Am J Physiol. 1997;273:E99–E107.

(2) McLESTER, JOHN & BISHOP, E & GUILLIAMS, M.E.. (2000). Comparison of 1 Day and 3 Days Per Week of Equal-Volume Resistance Training in Experienced Subjects. The Journal of Strength & Conditioning Research. 14. 10.1097/00005768-199905001-00443.

(3) Mangine GT, Hoffman JR, Gonzalez AM, et al. The effect of training volume and intensity on improvements in muscular strength and size in resistance-trained men. Physiol Rep. 2015;3(8):e12472. doi:10.14814/phy2.12472

(4) Schoenfeld BJ, Ogborn D, Krieger JW. Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis. Sports Med. 2016 Nov;46(11):1689-1697. doi: 10.1007/s40279-016-0543-8. PMID: 27102172.

(5) Schoenfeld BJ, Ogborn D, Krieger JW. Dose-response relationship between weekly resistance training volume and increases in muscle mass: A systematic review and meta-analysis. J Sports Sci. 2017 Jun;35(11):1073-1082. doi: 10.1080/02640414.2016.1210197. Epub 2016 Jul 19. PMID: 27433992.